Anti-Satellite Weapons, Countermeasures, and Arms Control

September 1985

NTIS order #PB86-182953 Recommended Citation: U.S. Congress, office of Technology Assessment, A nti-.%]h~llih’ W(wp(m.s, ( ‘(wnhv-- metisures, and Arms Cmh-of, (WA- 1.S(;-281 (Wash inglx)n, 1 W: (J .S. ( ;f)vt’r-ntm’nt I)rinting office, Sepkmher 1 985).

I.ibrary of Congress Catalog Card Number 85-600587”

For sale by the Superintendent of l)ocumcnts U.S. Government f’rinting office, Washington, 1)C 20402 Foreword

/// Advisory● Panel on New Ballistic Missile Defense Technologies

Iv OTA Project Staff on New Ballistic Missile Defense Technologies

Administrative Staff

Jannie Coles Dorothy Richroath Jackie Robinson Glossary of Acronyms and Terms

Glossary of Acronyms

Glossary of Terms they are deployed from a booster or post-boost Delta-V: A numerical index of the maneuverabil- vehicle until they are destroyed. ity of a satellite or rocket, It is the maximum Bistatic Radar: A radar system which has trans- change in velocity which a spacecraft could mitters and receivers stationed at two locations; achieve in the absence of a gravitational fieId. a special case of multistatic radar. Diffraction: The spreading out of electromagnetic Boost Phase: The phase of a missile trajectory radiation as it leaves an aperture, such as a mir- from launch to burnout of the final stage. For ror. The degree of spread, which cannot be elim- ICBMS, this phase typically lasts from 3 to 5 inated by focusing, is proportional to the ratio minutes, but studies indicate that reductions to of the wavelength of radiation to the diameter the order of 1 minute are possible. of the aperture. Brightness: In this report, the amount of power Digital Processing: The most familiar type of com- that can be delivered per unit solid angle by a puting, in which problems are solved through directed-energy weapon. the mathematical manipulation of streams of Capital Satellite: A highly valued or costly satel- numbers. lite, as distinct from an inexpensive decoy sat- Directed-Energy Weapon: A weapon that kills its ellite. Some decoys might be so expensive as to target by delivering energy to it at or near the be considered capital satellites. speed of light. Includes lasers and particle beam Chaff: Confetti-like metal foil ribbons which can weapons. be ejected from spacecraft (or terrestrial vehi- Discrimination: The ability of a surveillance sys- cles) to reflect enemy radar signals, thereby cre- tem to distinguish decoys from intended tar- ating false targets or screening actual targets gets, e.g., certain types of satellites. from the “view” of radar. Early Warning: In this report, early detection of Coherence: The matching, in space (transverse) or an enemy ballistic missile launch, usually by time (temporal coherence), of the wave structure means of surveillance satellites and long-range of different parallel rays of a single frequency radar. of electromagnetic radiation. This results in the Electromagnetic Radiation: A form of propagated mutual reinforcing of the energy of these differ- energy, arising from electric charges in motion, ent components of a larger beam. Lasers and ra- that produces a simultaneous wavelike varia- dar systems produce partially coherent ration in electric and magnetic fields in space. The diation. highest frequencies (or shortest wavelengths) of Command Guidance: The steering and control of such radiation are possessed by gamma rays, a missile by transmitting commands to it. which originate from processes within atomic Counter-countermeasures: Measures taken to de- nuclei. As one goes to lower frequencies, the feat countermeasures. electromagnetic spectrum includes X-rays, ul- Countermeasures: In this report, measures taken traviolet light, visible light, infrared light, by the offense to overcome aspects of a BMD microwave, and radio waves. system. Electron-volt: The energy gained by an electron in Dazzling: In this report, the temporary blinding passing through a potential difference of 1 volt. of a sensor by overloading it with an intense sig- 6.25 quintillion electron-volts equals 1 joule; nal of electromagnetic radiation, e.g., from a la- 22.5 billion trillion electron-volts equals 1 kilo- ser or a nuclear explosion. watt-hour. Decoy: An object that is designed to make an ob- Elliptical Orbit: A noncircular Keplerian orbit. server believe that the object is more valuable Endoatmospheric: Within the atmosphere; an en- than is actually the case. Usually, in this report, doatmospheric interceptor intercepts its target a decoy refers to a Iight object designed to look within the atmosphere. like a satellite. Ephemeris: A collection of data about the pre- Deep Space: The region of outer space at altitudes dicted positions (or apparent positions) of celes- greater than 3,000 nautical miles (about 5,600 tial objects, including artificial satellites, at va- kilometers) above the Earth’s surface. rious times in the future. A satellite ephemeris Defensive Satellite (DSAT) Weapon: A space- might contain the orbital elements of satellites based ASAT weapon that is intended to defend and predicted changes in these. satellites by destroying attacking ASAT Equatorial Orbit: An orbit above the Earth’s weapons. Equator. Defensive Technologies Study Team (DTST): A Excimer: A contraction for “excited dimer”; a type committee, generally known as the “Fletcher of lasant. A dimer is a molecule consisting of Panel, ” after its Chair, appointed by President two atoms. Some dimers—e.g., xenon chloride Reagan to investigate the technologies of poten- and krypton fluoride-are molecules which can- tial BMD systems. not exist under ordinary conditions of approxi-

vii mate thermal equilibrium but must be created above the Equator. A satellite placed in such in an “excited’ ’-i.e., energized-condition by an orbit revolves around the Earth once per day. special “pumping” processes in a laser. See Geostationary Orbit. Exoatmospheric: Outside the atmosphere; an exo- Gray: The Syst6me International unit of absorbed atmospheric interceptor intercepts its target in dose of ionizing radiation. One gray (abbrevi- space. ated 1 Gy) is 1 joule of absorbed energy per kilo- Fission: The breaking apart of the nucleus of an gram of matter. atom, usually by means of a neutron. For very Hard Kill: Destruction of a target in such a way heavy elements, such as uranium, a significant as to produce unambiguous visible evidence of amount of energy is produced by this process. its neutralization. When controlled, this process yields energy Hardness: A property of a target; measured by the which may be extracted for civilian uses, such power needed per unit area to destroy the tar- as commercial electric generation. When uncon- get by means of a directed-energy weapon. A trolled energy is liberated very rapidly: such fis- hard target is more difficult to kill than a soft sion is the energy source of uranium- and plu- target, tonium-based nuclear weapons; it also provides High-Earth Orbit: An orbit about the Earth at an the trigger for fusion weapons. altitude greater than 3,000 nautical miles (about Fratricide: In this report, the unintended destruc- 5,600 kilometers). tion of some of a nation’s weapons or other mil- Homing Device: A device, mounted on a missile, itary systems (e. g., satellites) by others. that uses sensors to detect the position or to Free-electron Laser: A type of laser which does not help predict the future position of a target, and use ordinary matter as a lasant but instead gen- then directs the missile to intercept the target. erates radiation by the interaction of an electron It usually updates frequently during the flight beam with a static magnetic or electric field. of the missile. Loosely speaking, free-electron laser technology Impulse: A mechanical jolt delivered to an object. resembles and evolved from that used by par- Physically, impulse is a force applied for a pe- ticle accelerators (“atom smashers”). Lasers riod of time, and the Systi$me Internationale which are not freeelectron lasers are bound- unit of impulse is the newton-second (abbre- electron lasers. viated N-s). See Impulse Intensity. Functional Kill: The destruction of a target by dis- Impulse Intensity: Mechanical impulse per unit abling vital components in a way not immedi- area. The Systeme International unit of im- ately detectable, but nevertheless able to pre- pulse intensity is the pascal-second (abbreviated vent the target from functioning properly. An Pa-s) A conventionally used unit of impulse in- example is the destruction of electronics in a tensity is the “tap,” which is one dyne-second guidance system by a neutral particle beam. per square centimeter; hence 1 tap = 0.1 Pa-s. Fusion: More specifically, nuclear fusion: The fus- Impulse Kill: The destruction of a target, using ing of two atomic nuclei, usually of light ele- directed energy, by ablative shock. The inten- ments, such as hydrogen. For light elements, sity of directed energy maybe so great that that energy is liberated by this process. Hydrogen the surface of the target violently and rapidly bombs produce most of their energy through boils off delivering a mechanical shock wave to the fusion of hydrogen into helium. the rest of the target and causing structural Graser: See Gamma-ray Laser. failure. Gamma-ray Laser: A laser which generates a beam Inclination: The inclination of an orbit is the (di- of gamma rays; also called a graser. A gamma- hedral) angle between the plane containing the ray laser, if developed, would be a type of X-ray orbit and the plane containing the Earth’s laser; although it would employ nuclear reac- Equator. An equatorial orbit has an inclination tions, it need not (but might) employ nuclear fis- of 00 for a satellite traveling eastward or 1800 sion or fusion reactions or explosions. for a satellite traveling westward. An orbit hav- Gamma Rays: X-rays emitted by the nuclei of ing an inclination between 00 and 900 and in atoms. which a satellite is traveling generally eastward Geostationary Orbit: An orbit at an altitude of is called a prograde orbit. An orbit having an 35,800 kilometers above the Earth’s Equator. inclination of 900 passes above the north and A satellite placed in such an orbit revolves south poles and is called a polar orbit. An orbit around the Earth once per day, maintaining the having an inclination of more than 900 is called same position relative to the surface of the a retrograde orbit. Earth. It then appears to be stationary, and can Ionization: The removal or addition of one or more be used as a communications relay or as a sur- electrons to a neutral atom, forming a charged veillance post. ion. Geosynchronous Orbit: An orbit about 35,800 km Isotropic: Independent of direction; referring to Vlll. . . the radiation of energy, it means “with equal crowaves. The light is bounced off a target and intensity in all directions, ” i.e., omnidirectional. then detected, with the return beam providing Isotropic Nuclear Weapon (INW): A nuclear explo- information on the distance and velocity of the sive which radiates X-rays and other forms of target. radiation with approximately equal intensity in Limited Test Ban Treaty: The multilateral Treaty all directions. The term “isotropic” is used to signed and ratified by the United States and the distinguish them from nuclear directed-energy U.S.S.R. in 1963 which prohibits nuclear tests weapons. in all locations except underground. Joule: The Systeme International unit of energy. Megawatt: One million watts; a unit of power. A One kilowatt-hour is 3.6 million joules. typical commercial electric plant generates Keep-out Zone: A volume around a space asset, off about 500 to 1,000 megawatts. limits to parties not owners of the asset. Keep- MeV: One million electron-volts. A unit of energy out zones could be negotiated or unilaterally usually used in reference to nuclear processes. declared. The right to defend such a zone by It is equivalent to the energy that & electron force and the legality of unilaterally declared gains in crossing a potential of 1 million volts. zones under the Outer Space Treaty remain to Micron: One-millionth of a meter (equivalently, be determined. one-thousandth of a millimeter). Roughly twice Kelvin Temperature: A scale of temperature on the wavelength of visible light. which zero degrees Kelvin (abbreviated 00 K) Midcourse Phase: The phase of a ballistic missile corresponds to “absolute zero. Temperature in trajectory in which the RVS travel through degrees Kelvin equals temperature in degrees space on a ballistic course towards their targets. Celsius plus 273.16, thus ice melts at 273.16 G This phase lasts up to 20 minutes. K, and water boils at 373.16° K. Military Satellite (MILSAT): A satellite used for Keplerian Orbit: The orbit which a satellite would military purposes, such as navigation or intel- follow if the Earth were a uniform sphere with ligence gathering. no atmosphere, and if other simplifying assump- Miniature Homing Vehicle (MHV)/Miniature Vehicle tions were valid. Such an orbit would be an el- (MV): An air-launched direct-ascent (“pop-up”) lipse having the center of the Earth as one fo- kinetic-energy ASAT weapon currently being cus. A special case of such an orbit is a circular developed and tested by the U.S. Air Force. orbit about the center of the Earth. Monostatic Radar: A radar system in which the Kill Assessment: The detection and assimilation receiver and transmitter are colocated. of information indicating the destruction of an Multistatic Radar: A radar system that has trans- object under attack. Kill assessment is one of mitters and receivers stationed at multiple loca- the many functions to be performed by a bat- tions; typically, a radar system with a transmitter tle management system. and several receivers, all of which are geo- Kinetic-Energy Weapon: A weapon that uses ki- graphically separated. A special case is bistatic netic energy, or energy of motion, to kill an ob- radar. An advantage of multistatic radar over ject. Weapons that use kinetic energy are a monostatic radar is that even if transmitters— rock, a bullet, a nonexplosively armed rocket, which might be detected by the enemy when and an electromagnetic radgun. operating-are attacked, receivers in other loca- Lasant: A material that can be stimulated to pro- tions might not be noticed and might thereby duce laser light. Many materials can be used as escape attack. lasants; these can be in solid, liquid, or gaseous Obscur-&.nt: A material-e. g., smoke or chaff-used form (consisting of molecules–including exci- to conceal an object from observation by a ra- mers— or atoms) or in the form of a plasma (con- dio or optical sensor. Smoke maybe used to consisting of ions and electrons). Lasant materials ceal an object from observation by an optical useful in high-energy lasers include carbon di- sensor, and chaff may be used to conceal an ob- oxide, carbon monoxide, deuterium fluoride, ject from observation by a radio sensor (e.g., hydrogen fluoride, iodine, xenon chloride, kryp- radar). ton fluoride, and selenium, to mention but a few. On-line: Operating, as distinct from dormant. Laser: A device that produces a narrow beam of Orbital Elements: Any set of several parameters coherent radiation through a physical process (e.g., apogee, perigee, inclination, etc.) used to known as stimulated emission. Lasers are able specify a Keplerian orbit and the position of a to focus large quantities of energy at great dis- satellite in such an orbit at a particular time. tances, and are among the leading candidates Seven independent orbital elemets are required for BMD weapons. to umambiuously specify the position of a sat- LIDAR: A technique analogous to radar, but ellite in a Keplerian orbit at a particular time. which uses laser light rather than radio or mi- Outer Space Treaty of 1967: A multilateral treaty

ix signed and ratified by both the United States formation can be used for tracking, aiming, dis- and the Soviet Union. Article IV of the Outer crimination, attacking, kill assessment, or all of Space treaty forbids basing nuclear weapons or the above. Sensors may detect any type of elec- other weapons of mass destruction in space. tromagnetic radiation or several types of nu- Passive Sensor: One that detects naturally occur- clear particles. ring emissions from a target for tracking and/or Shoot-back In this report, the technique of defend- identification purposes. ing a space asset by shooting at an attacker. Perigee: The minimum altitude attained by an Signature: Distinctive type of radiation emitted Earth satellite. or reflected by a target, which can be used to Phased-Array Radar (PAR): A radar with elements identify that target. that are physically stationary, but with a beam Simulation: The art of making a decoy look like that is electronically steerable and can switch a more valuable strategic target See Anti-simu- rapidly from one target to another. Used for lation. tracking many objects, often at great distances. Slew Time: The time needed for a weapon to reaim Pointing: The aiming of sensors or defense weap- at a new target after having just fired at a pre- ons at a target with sufficient accuracy either vious one. to track the target or to aim with sufficient ac- Smoke: An obscurant which may be used in the curacy to destroy it. atmosphere or in space to conceal an object Polar Orbit: An orbit having an inclination of900. from observation by an optical sensor. Prograde Orbit: An orbit having an inclination of Soft Kill: Same as functional kill. between 0° and 90°. See Retrograde Orbit. Space Detection And Tracking System (SPADATS): Pumping: In this report, the raising of the mole- A network of space surveillance sensors oper- cules or atoms of a lasant to an energy state ated by the U.S. Air Force. above the normal lowest state, in order to pro- Space Mines: Hypothetical devices that can track duce laser light. This results when they fall back and follow a target in orbit, with the capability to a lower state. Pumping may be done using of exploding on command or by pre-program, electrical, chemical, or nuclear energy. in order to destroy the target. Rad: A unit of absorbed dose of ionizing radiation. Stimulated Emission: Physical process by which One rad is 0.001 gray. an excited molecule is induced by incident ra- Radar: A technique for detecting targets in the diation to emit radiation at an identical fre- atmosphere or in space by transmitting radio quency and in phase with the incident radiation. waves (e.g., microwaves) and sensing the waves Lasers operate by stimulated emission. reflected by objects. The reflected waves (called Superfluorescence: See Superradiance. “returns” or “echos”) provide information on Superradiance: The process used by a superradiant the distance to the target and the velocity of laser to generate or amplify a laser beam in a the target and may also provide information single pass through a lasant material, or—in the about the shape of the target. (Originally an case of a free-electron laser—through an electric acronym for “RAdio Detection And Ranging.”) or magnetic field in the presence of an electron Radian: A unit of angular measure. One radian is beam. Superradiance is actually a form of stim- about 57.30. One microradian (0.000001 radian) ulated emission. Also known as superfluores- is the angle subtended by an object 1 meter cence, or amplified spontaneous emission. across at a distance of 1,000 kilometers. Superradiant Laser: A laser in which the beam Reaction Decoy: A decoy deployed only upon passes through the lasant only once; mirrors are warning or suspicion of imminent attack. not required for the operation of such a laser, Reentry: The return of objects, originally launched as they are with more conventional lasers which from Earth, into the atmosphere. are sometimes called “cavity lasers” to distin- Retrograde Orbit: An orbit having an inclination guish them from superradiant lasers. Free-elec- of more than 900. See Prograde Orbit. tron lasers may also be superradiant; the laser Robust: In this report, describing a system, in- beam of a superradiant free-electron laser would dicating its ability to endure and perform its pass once through an electric or magnetic field mission against a reactive adversary. Also used (instead of a lasant) in the presence of an elec- to indicate ability to survive under direct tron beam. attack. Synthetic Aperture Radar (SAR): A radar system Salvage-fused: Describing a warhead, that is set which correlates the echoes of signals emitted to detonate when it is attacked. Usually refers at different points along a satellite’s orbit or an to a nuclear warhead. airplane’s flight path. The highest resolution Sensors: Electronic instruments that can detect ra- achievable by such a system is theoretically diation from objects at great distances. The in- equivalent to that of a single large antenna as x wide as the distance between the most widely tracks predicted by the defensive system, using spaced points along the orbit that are used for several observations and physical laws. transmitting positions. In practice, resolution Warhead: A weapon, usually a nuclear weapon, will be limited and by the radar receiver’s signal- contained in the payload of a missile. processing capability or by the limited coher- World-Wide Military Command and Control Sys- ence of the radio signal emitted by the radar tem (WWMCCS): A communications network transmitter. linking U.S. forces. Thermal Kill: The destruction of a target by heat- X-ray Laser: A laser which generates a beam or ing it, using directed energy, to the degree that beams of X-rays. Also called an “x-raser” or structural components fail. “XRL.” Threat: The anticipated inventory of enemy weap- X-rays: Electromagnetic radiation having wave- ons and method of using them. lengths shorter than 10 nanometers (10 bil- Tracking: The monitoring of the course of a mov- lionths of a meter). ing target. Ballistic objects may have their

xl Contents

Page I. Executive Summary ...... 3

2. Anti-Satellite Weapons, Countermeasures, and Arms Control ...... 25

3. MILSATs, ASATs, and National Security ...... 33

4. ASAT Capabilities and Countermeasures ...... 49

5. ASAT Arms Control: History...... 91

6. ASAT Arms Control: Options...... 105

7. Comparative Evaluation of ASAT Policy Options ...... 125

Appendix A: Text of the 1983 Soviet Draft Treaty on the Prohibition of the Use of Force in Outer Space and From Space Against the Earth ...... 145 Chapter 1 Executive Summary Contents

Page Introduction ...... 3 Principal Findings ...... 3 Comparison of Potential ASAT and Arms Control Regimes ...... 13 1. Existing Constraints...... 13 2. Comprehensive ASAT and Space-Based Weapon Ban ...... 14 3. ASAT Weapon Test Ban and Space-Based Weapon Deployment Ban 15 4. One Each/No New Types ...... 17 5. “Rules of the Road” for Space ...... 17 6. Space Sanctuary ...... 18 7. Space-Based BMD ...... 19 Treaties of Limited Duration...... 20

Tables Table No. Page l-1. Effect of Regimes on ASAT Development and Arms Control ., ...... ,13 l-2. Sensor Technology for Compliance Monitoring ...... 16 Chapter 1 Executive Summary

INTRODUCTION

For over two decades the United States and clear whether such survivability measures will the Soviet Union have used satellites for mil- be adequate to guard against the highly de- itary purposes. As a result of recent techno- veloped ASAT threats of the future. Another logical advances, military satellites will soon possible contributor to satellite survivability be able to play a more significant role in ter- is mutually agreed arms control. A judicious restrial conflicts. These space assets will be combination of certain arms control measures able to supply more types of information, more and unilateral satellite survivability measures rapidly, to more diverse locations. Some will might provide more security to U.S. military carry out target acquisition, tracking, and kill satellites than either type of measure alone. assessment functions, thus operating more At the same time, however, arms control directly than before as components of weap- measures which constrained the threat to U.S. ons systems. satellites would also constrain the ability of This growing military utility also makes sat- the United States to weaken Soviet military ellites attractive targets for opposing military capabilities by attacking their satellites in forces. Both the Soviet Union and the United time of war. In addition, limits on ASATS States have been developing anti-satellite would severely limit the kinds of ballistic mis- (ASAT) weapons. These weapons could weaken sile defense weapons that might be deployed the opponent’s military capabilities by depriv- in the future. (The subject of ballistic missile ing his forces of the services of some satellites. defense is dealt within a companion OTA re- The existing Soviet anti-satellite weapons— port, Balistic Missile Defense Technologies.) and future, potentially more effective ASATS This report explains the dilemmas facing –pose a growing defense problem for the U.S. policymakers and assesses the pros and United States. cons of some options for dealing with the chal- A variety of unilateral measures, passive lenge of anti-satellite weapons, particularly in and active, may improve the survivability of the light of projected future weapons tech- U.S. military satellites. At present, it is un- nology.

PRINCIPAL FINDINGS Current Soviet military satellites pose though not “weapons” themselves, support only a limited threat to U.S. military ca- and enhance the effectiveness of terrestrial So- pabilities, but future space systems will viet forces that would engage in direct com- pose a greater threat. bat. For example, if navigation satellites improve munition delivery accuracies, then fewer The Soviet Union currently uses satellites munitions are required to accomplish a given to perform a wide variety of tasks including missile launch detection, communications, objective. The growing military utility of sat- navigation, meteorological surveillance, pho- ellites has rekindled U.S. interest in ASAT tographic and radar reconnaissance, and col- weapons. lection of electromagnetic intelligence (e.g., Some Soviet satellites already supply lim- radar emissions). Many of these satellites, al- ited targeting information to other terrestrial

3 4

assets. The Administration has expressed its These options include nondestructive as well concern about: as destructive measures; those presented below are not mutually exclusive. . . . present and projected Soviet space systems which, while not weapons themselves, ● Possible nondestructive responses to So- are designed to support directly the viet MILSATs: U. S. S.R. ’S terrestrial forces in the event of –Force Augmentation: U.S. combat or a conflict. These include ocean reconnais- support forces could be increased to sance satellites which use radar and elec- counter the increase in effectiveness tronic intelligence in efforts to provide targeting data to Soviet weapon platforms which Soviet forces could derive from which can quickly attack U.S. and allied sur- use of military satellites. Force augmen- face fleets. ’ tation is often, but not always, more costly than other means of mitigating At present Soviet radar (RORSAT) and elec- the threat posed by Soviet military sat- tronic intelligence (EORSAT) ocean reconnais- ellites. sance satellites pose only a limited threat to –Passive Countermeasures: By using U.S. and allied surface fleets. RORSATS and passive measures to conceal or disguise EORSATS are typically deployed at altitudes their identity and nature, U.S. forces and inclinations which offer limited observa- could reduce the utility of Soviet recon- tion range. Although the observation “swath” naissance satellites. For example, as- of these satellites will eventually cover most sets now detectable by radar might be of the Earth, if only one or two of these satel- redesigned to reflect radar signals only lites are operational-as has been customary weakly in order to evade detection by in peacetime-then a ship would be exposed radar satellites, or radio silence might to observation only intermittently and might be practiced, or covert signaling tech- successfully evade the satellite. The Soviet niques used to prevent detection by sat- Union could increase the number of deployed ellites that collect signals intelligence. RORSATS and EORSATS, thereby making –Electronic Countermeasures and Electro- evasion more difficult. Other countermeasures optical Countermeasures: Electronic coun- exist which could further reduce the threat termeasures such as “jamming” (i.e., posed by these satellites, but such measures overloading enemy receivers with might not be available to merchant resupply strong signals) and “spoofing” (i.e., vessels operating during a protracted non- sending deceptive signals) could be used nuclear conflict. to interfere with satellite functions. In the future, sophisticated communication, Electro-optical countermeasures such navigation, and surveillance satellites are as “dazzling” (temporary “blinding”) or likely to play a greater role in all levels of ter- spoofing optical sensors are also avail- restrial conflict. This will increase the incen- able. However, these countermeasures tive for both the United States and the Soviet —especially spoofing—require detailed Union to develop and deploy ASAT weapons. knowledge of the satellite systems (e.g., operational frequencies, receiver sensi- tivity, etc.) against which they are Possible responses to the threat posed directed. by Soviet military satellites are numer- ● Possible Destructive Responses to Soviet ous and diverse. MILSATs: A variety of options are available to miti- –Inadvertent But Inherent ASAT Capa- gate the threat to U.S. and allied security bilities: The inherent ASAT capabilities posed by Soviet military satellites (MILSATS). of nuclear weapons such as ICBMS and SLBMS could be used to destroy low- ‘President Ronald Reagan, Report to the Congress: U.S. Po]- altitude Soviet satellites; with some icy on ASAT Arms Control, Mar. 31, 1984. modifications, these weapons might 5

also be used to attack satellites at Although national utility for space system higher altitudes. Some types of non- support is difficult to assess precisely and nuclear interceptors (e.g., that demon- meaningless to compare between nations, it strated in the U.S. Army’s 1984 Hom- is apparent that the United States is more de- ing Overlay Experiment (HOE)) which pendent on MILSATS to perform important might eventually be developed and de- military functions than is the Soviet Union. ployed for BMD purposes, would have The United States has global security commit- some inherent ASAT capability. Fi- ments and force deployments, while the Soviet nally, any highly maneuverable space- Union has few forces committed or deployed craft capable of noncooperative rendez- outside the borders and littoral waters of mem- vous—e.g., the U.S. Space Shuttle—has bers of the Warsaw Treaty Organization and some ASAT potential. Cuba. The United States has corresponding —Planned ASAT Weapons: When oper- requirements for global and oceanic command ational, the current USAF MV ASAT and control communications (C3) capabilities weapon will be able to destroy Soviet and relies largely on space systems to provide military satellites in low-Earth orbit. these requirements. The Soviet Union, on the –Advanced ASAT Weapons: Space- or other hand, can rely on landline communica- ground-based directed-energy weapons tions systems and over-the horizon radio links or advanced kinetic-energy weapons for many of its C’ needs. Satellite communi- could be developed that would be able cations links are used by the Soviet Union but to destroy Soviet satellites beyond the are not as essential as those of the United range of existing or planned U.S. ASAT States. In addition, the Soviet Union has weapons. greater capability to reconstitute satellites which are lost in action; hence even to the ex- The United States is now more depen- tent the Soviet Union is dependent on space dent on satellites to perform important system support, it is less dependent on indi- military functions than is the Soviet vidual satellites for some functions. The Union. United States also has fewer alternative ter- In choosing between ASAT weapon devel- restrial means for collecting intelligence than opment and arms control, one wishes to pur- does the Soviet Union, which can exploit the sue that course which makes the greater con- freedom and openness of U.S. society for this tribution to U.S. national security. This is purpose. often characterized as a choice between developing a capability to destroy Soviet satellites Soviet ASAT capabilities threaten U.S. while assuming U.S. satellites will also be at military capabilities to some extent now risk, or protecting U.S. satellites to some ex- and potentially to a much greater extent tent through arms control while forfeiting ef- in the future. fective ASAT weapons. The better choice could, in principle, be identified by comparing The Soviet Union tested a coorbital satel- the utility which the United States expects to lite interceptor system from 1968 until its self- derive from its military satellites with the dis- imposed moratorium of August 1983. The utility which the United States would expect Reagan Administration considers this ASAT to suffer from Soviet MI LSATS during a con- system to be operational. The interceptors are flict. Such a comparison-although possible in believed to be capable of attacking satellites principle–is made exceedingly difficult by the at altitudes of up to 5,000 kilometers, depend- number of conflict scenarios which must be ing on their orbital inclination. At present considered and by the lack of consensus or offi- there appear to be only two launchpads for So- cial declaration about the relative likelihood viet coorbital interceptors, both located at and undesirability of each scenario. Tyuratam. 6

attractive targets. Both the United States and the Soviet Union have been developing anti-satellite (ASAT) weapons

The existing Soviet ASAT weapon may be The current Soviet interceptor and the effective for negating low-altitude U.S. mili- booster that it has been tested with cannot tary satellites, such as are used for navigation reach critical U.S. early warning and commu- (Transit), meteorological surveillance (Defense nication satellites in high orbits. If the Soviet Meteorological Support Program satellites), ASAT weapon were mated with a larger boost- and other purposes. Assistant Secretary of De er—a procedure which has yet to be tested— fense Richard Perle has stated: it might be able to reach these U.S. satellites. We believe that this Soviet anti-satellite ca- In addition to the coorbital interceptor, the pability is effective against critical U.S. sat- Soviet Union is testing ground-based lasers ellites in relatively low orbit, that in wartime which the Reagan Administration believes we would have to face the possibility, indeed have ASAT capabilities. The U.S. Department the likelihood, that critical assets of the of Defense estimates that the U.S.S.R. could United States would be destroyed by Soviet test a space-based laser within the decade.3 anti-satellite systems. . . . If, in wartime, the Soviet Union were to attack critical satellites Advanced directed-energy weapons such as on which our knowledge of the unfolding con- lasers and particle beam weapons–if devel- ventional war depended, . . . we would have oped and deployed—could give the Soviets an little choice but . . . to deter continuing at- “all altitude, “ “instantaneous kill” capability. tacks on our eyes and ears, without which we As the United States increases its reliance on could not hope to prosecute successfully a space systems to perform vital military func- conventional war. z tions (e.g., the MILSTAR communication satellite system), an increase in Soviet ASAT ca- ‘Statement of The Honorable Richard Perle, Assistant Sec- pabilities could create a significant threat to retary of Defense (International Security Policy), in Hearings U.S. national security. before the Subcommittee on Strategic and Theater Nuclear Forces of the Senate Comm”ttee on Armed Services: Review of the FY 1985 Defense Authorization Bill, Mar. 15, 1984 ‘U.S. Department of Defense, Soviet Military Power, 1985, [S.Hrg. 98-724, Pt. 7., p. 3452]. p. 44. 7 .

Aside from its intentional ASAT capabil- tional or nuclear explosive charge, a space ities, the Soviet Union could currently attack mine would destroy its quarry almost ins- low-altitude satellites with its nuclear ABMs, tantly on command or (if salvage-fused) ICBMs, and SLBMS. With some modification, when attacked or disturbed. these nuclear assets might also be used to at- High-Power Radio-Frequency Weapons: tack satellites in higher orbits. Current Soviet These would be devices capable of produc- spacecraft (i.e., Soyuz, Salyut), because of their ing intense, damaging beams of electro- limited maneuter and rendezvous capabilities, magnetic radiation that could be used to do not hate a significant ASAT potential. Fu- jam communication and radar systems at ture Soviet spacecraft, such as the expected low power levels or to overload and burn Soviet “Shuttle” and space plane, will have out satellite electronics at higher power greater inherent ASAT capabilities. The So- levels; viets also have the technological capability to High-Energy Laser Weapons: High-ener- conduct electronic warfare against space gy lasers may eventually be capable of systems. producing intense, damaging beams of electromagnetic radiation that could jam Several technologies on the horizon optical communication and sensor sys- could lead to a new generation of highly tems at low power levels or cause perma- capable ASATS. nent damage at higher power levels. Ground-based lasers would have infre- ‘1’he following advanced ASATS could be de- quent opportunities to attack satellites \“eloped and deployed b~~ either the United but, unless attacked themselves, could States or the Soviet Union: shoot inexpensively and repeatedly. ● 5’pace Alines.a These would be deployed Space-based reflectors could also be used within lethal range and would continu- to relay laser beams from ground-based ousl~’ trail their target. Using a conven- lasers to their targets. Spacebased lasers

,/’

Artist’s conception of high-energy laser facility at the Sary Shagan test facility in the Soviet Union,

H!gh-energy lasers may eventually be effective ASAT weapons, Ground-based lasers would have Infrequent opportunities to attack satellites, but, unless attacked themselves. could shoot inexpensively and repeatedly, 8

might be able to attack several satellites riety of ASAT weapons and will be par- in quick succession; space-based X-ray ticularly economical for the protection lasers might be able to attack several sat- of small satellites capable of being imi- ellites instantly and simultaneously. tated by small, cheap decoys. Combina- ● Neutral Particle Beam Weapons: Power- tions of these passive responses—e.g., ful particle accelerators, similar to those decoys for “dark” spare satellites– now used in scientific research, might could offer even greater protection than eventually be developed which could de- individual measures alone. stroy the hardened electronics of a —Active Countermeasures: Active coun- spacecraft. termeasures may be destructive or non- ● Kinetic-Energy Weapons: Space- or destructive. Destructive countermeas- ground-based kinetic-energy weapons ures could include giving satellites a (similar to the current U.S. MV ASAT) self-defense capability or providing crit- would probably be small, homing vehicles ical satellites with an escort defense. that destroy their target by colliding with Nondestructive countermeasures might it at extremely high velocities. include electronic countermeasures and electro-optical countermeasures such as jamming. Attacking Soviet ASAT con- Possible U.S. responses to the Soviet trol facilities is also a potential-though ASAT threat are numerous and diverse. dangerous— active countermeasure. The United States could respond to the –Deterrence: The Soviets might be de- threat posed by the Soviet ASAT threat in terred from attacking U.S. satellites if several ways; both unilateral and diplomatic the United States declared its willing- options are available. ness to retaliate for attacks on U.S. space assets. Such retaliation could be ● Possible unilateral responses to Soviet against Soviet space assets, in which ASATS: case the United States would need a ca- –Reduce Dependence on Military Satel- pable ASAT weapon, or it could be lites: No matter what satellite surviv- against Soviet terrestrial assets. The ability or arms control measures are former alternative assumes that the taken, there will always be some risk Soviets value the preservation of their that critical satellites can be destroyed satellites at least as highly as they or rendered inoperable. The United value the destruction of U.S. satellites. States must exercise caution in the ex- The latter alternative, of course, carries tent of its reliance on space assets to a greater risk of uncontrolled escalation perform tasks essential to the national if deterrence should fail. security. Nonetheless, some space sys- –Keep-Out Zones: The United States tems perform vital military functions could declare and defend protective which cannot be duplicated—or can be zones around critical satellites. duplicated only imperfectly-by terres- Defended keep-out zones could offer sig- trial systems. nificant protection against current –Passive Countermeasures: Passive ASAT weapons for some satellites. This countermeasures such as hiding, decep- subject is discussed in detail below. tion (use of decoys), evasion (maneuver- Possible diplomatic responses to Soviet ing), hardening (making satellites more ASATS: durable), and proliferation (adding more –Arms Control; The United States, the satellites) all offer significant protection Soviet Union, and other spacefaring na- from the current and perhaps future So- tions could negotiate limitations on the viet A SAT weapons. Decoys would testing, deployment, or hostile use of probably be effective against a wide va- anti-satellite systems. 9 . —

–Rules of the Road: The United States, neutral particle beam weapon could cost more the Soviet Union, and other spacefar- than it would to scale up the weapon to pene- ing nations could negotiate restrictions trate the shielding, and such a weapon could on potentially provocative activities in slew its beam quickly enough to make evasion space, such as unexplained close ap- infeasible. With such a weapon it might be as proaches to foreign satellites or irradi- economical to damage spare satellites as they ation of foreign satellites with low- are brought “on line’ as it would be to dam- power directed-energy beams. With age initially operational satellites. such agreed restrictions in force, these activities would justify defensive or Active measures, such as “shoot-back” with retaliatory measures. a weapon of longer effective range, could provide protection against some A SAT weapons but not against weapons such as space mines Of the future ASAT weapons now fore- or single-pulse lasers which could destroy sat- seeable, those which would be most effec- ellites instantly and without warning. How- tive if used in a preemptive or aggressive ever, it might not be economical to attack sat- surprise attack would be space-based and ellite systems composed of many small, cheap therefore subject to attack by similar satellites—and possibly decoys as well—with weapons. expensive advanced ASAT weapons. Such sat- Preemptive attack would be an attractive ellites could perform a number of important countermeasure to space-based ASAT weap- functions (e.g., communication or navigation) ons. If each side feared that only a preemp- without encouraging a proliferation of ad- tive attack could counter the risk of being vanced weapons to attack them. Therefore, al- defeated by enemy preemption, then a crisis though it would be difficult to protect individ- situation could be extremely unstable. While ual satellites, satellite systems performing salvagefusing, if it proved practicable, would some critical functions might retain a fair de- diminish this risk, it would create a risk of gree of survivability. space war breaking out by accident. For example if a meteoroid destroyed a satellite, it might set off a chain reaction of salvage fusing which would destroy all satellites. To the A commitment to satellite survivability is important whether or not ASAT de- extent that protection was sought through velopment, or arms control, or both, are “shoot-back” rather than “shoot-first” tactics, a premium would be placed on having the big- pursued. gest and best ASATS deployed, which could The United States should place more empha- lead to an intense arms race. sis on means to ensure the survivability of critical military satellites and, particularly, their associated ground stations and data links, Foreseeable passive or active counter- regardless of whether ASAT limitations are measures may be inadequate to guaran- agreed upon. The existence of non-ASAT tee the survival of large inilitary satellites weapons (e.g., ICBMS, ABMs) and space sys- attacked by advanced ASAT weapons. tems (e.g., maneuverable spacecraft) with Passive or active countermeasures might some inherent ASAT capability makes it im- have only limited effectiveness against very possible to ban the ability to attack satellites. advanced ASAT or BMD weapons. For exam- Therefore, even under the most restrictive ple, it might be uneconomical to rely on pas- ASAT arms control regime, programs for sat- sive measures to protect large and expensive ellite survivability and countermeasures must satellites from a powerful neutral particle be pursued. In the absence of arms control beam weapon. Shielding satellites against a limitations on ASATS, ensuring satellite sur- 10

viability will be a more demanding task since United States might announce a “no first highly capable directed-energy ASAT weap- strike but possible first use’ policy for the em- ons or space mines could be deployed. ployment of ASAT weapons as it has for the employment of nuclear weapons. In the absence of restrictions on the development or deployment of ASAT weap- If defensive satellites (DSATS) are deployed ons, satellite survivability can be en- by the United States to defend its satellites, hanced if the United States is willing to or if certain satellites are given self-defense ca- negotiate or declare keep-out zones and pabilities, the United States would have to de is able thereafter to defend such zones cide under what circumstances it would use against unauthorized penetration by for- these assets and whether it wished to publicly eign spacecraft. announce this employment policy. The United Although passive or active countermeasures States might declare in advance that it would alone may be insufficient to protect satellites, fire at satellites suspected of being ASATS if if combined with keep-out zones they could of- they approached U.S. satellites within possi- fer a significant degree of protection from cer- bly lethal range. However, such a declaration tain ASAT weapons. Without keep-out zones would have an uncertain legal status and space mines could be predeployed next to all might generate considerable political opposi- critical military space systems. A keep-out tion from both spacefaring and non-space- zone of sufficient size would reduce the effec- faring nations. tiveness of such weapons. However, advanced, directed-energy or kinetic energy ASAT weap- Certain arms control provisions would ons may be able to function effectively even reduce the probability that advanced outside very large keep-out zones. ASATS will be developed or deployed. However, arms control could not guarantee the survival of U.S. satellites attacked Should ASAT development be pur- by residual or covert Soviet ASAT sued, the United States will need to for- weapons. mulate an employment policy. Arms control provisions, such as a ban on At present, no clear consensus exists among all testing of all systems “in an ASAT mode,” those Administration military space policy would reduce the likelihood that the Soviet analysts and executives interviewed by OTA Union could successfully develop and deploy on the conditions under which the United advanced, highly capable ASAT weapons. The States would attack foreign satellites or on the categories of weapons eliminated might in- manner in which it would retaliate for an at- clude space mines capable of “shadowing” val- tack on U.S. satellites. If the United States uable military assets in any orbit, directed- continues with its ASAT development and de- energy weapons with kill radii of hundreds to ployment plans, it will be necessary to formu- thousands of kilometers, and advanced kinet- late an employment policy. ic-energy weapons. In the absence of an agree- If the United States wishes to enhance the ment limiting their development, each side deterrent value of its ASAT weapons, it may would have a strong incentive to seek contin- choose to publicize certain aspects of its em- ually more effective means to attack threat- ployment policy. It might, for example, prom- ening satellites and to defend valuable assets. ise that the United States would not use its In the absence of adequate countermeasures, ASAT capabilities in an aggressive or preemp- the “instantaneous kill” capability of some ad- tive first strike but might use them in a defen- vanced ASATS might be destabilizing in a cri- sive or retaliatory reaction to an attack sis, because they would give each side an in- against the United States or its allies, even if centive to “shoot first” or else risk the loss U.S. satellites were not attacked. That is, the of its space assets. 11

Photo cred(l Lockheed Photo cred{t U S Deparfment of Defense Launch of U.S. Homing Overlay Experiment (HOE) to Artist’s conception of the Soviet GALOSH ABM test nonnuclear anti-ballistic missile technology, interceptor currently deployed around Moscow.

ABM interceptors may have some inherent ASAT capabilIties, ABMs, as well as ICBMS and SLBMS, present a threat which may not be easily resolved through arms control,

A ban on testing weapons in an A SAT mode ing satellites which might be booby-trapped. would be less effective at reducing the threat However, the range, effectiveness, and re- posed by weapon systems with inherent action time of even advanced maneuverable ASAT capability and by the existing Soviet spacecraft not designed as weapons would be ASAT weapon. ICBMS, SLBMS, and ABM in- substantially less than those of intentional terceptors with nuclear payloads are examples ASAT weapons. Although the development of of systems with residual ASAT capability. Al- maneuverable spacecraft would not be in- though these systems lack the kind of preci- hibited by most ASAT testing limitations, sion guidance necessary to actually collide some limits could be placed on operating them with a satellite, the long-range destructiveness “in an ASAT mode. ” of their nuclear payloads makes them poten- Arms control provisions might substi- tially effective ASATS. The Shuttle’s recent tute for passive and active countermeas- success at retrieving satellites strongly sug- ures in reducing the threat posed by gests the ASAT potential of future maneuver- ASAT weapons, but arms control would able spacecraft, although costly vehicles like be more effective if combined with coun- the Shuttle would probably not risk approach- termeasures. 12

U.S. satellites can be protected either by in- have excellent ASAT capabilities, any ASAT creasing their survivability or by reducing the limitation or test ban would almost certainly threat posed by Soviet ASAT weapons. Pas- impede BMD development. Conversely, tech- sive or active countermeasures are designed nology development ostensibly for advanced to do the former while arms control provisions ASAT systems might provide some limited would hopefully do the latter. In considering BMD capabilities, or, at minimum, informa- the advantages and disadvantages of ASAT tion useful in BMD research. arms control, ASAT development, and coun- Some available unilateral actions have clear termeasures, it is important to consider them benefits: in packages. A combination of arms control provisions and passive countermeasures, for ● Deployment of attack sensors on valuable example, or of passive countermeasures and satellites in order to provide information active countermeasures, could provide greater to support a retaliation decision; security than each component of such a pack- ● Deployment of a space-based, space sur- age might provide alone. veillance system in order to provide information to support verification of compliance with future arms control agreements; The benefits of most ASAT limitations to provide warning information required conflict with the benefits of ASAT exploi- for effective evasion or dispensing of de tation. coys; to support a decision to retaliate in Although ASAT arms control might pre- the event of an attack; and to provide in- vent the Soviet Union from developing ad- formation required for the targeting of 4 vanced, highly capable ASAT weapons, it ASAT/DSAT weapons ; would also place a similar restriction on the ● Hardening of military satellites against United States. Therefore, although U.S. sat- nuclear effects to a modest degree in or- ellites might be less vulnerable to ASAT at- der to preclude “cheap kills” by nuclear- tack, the United States would have to give up armed ICBMS, SLBMS, or ABMs; the ability to strike at Soviet satellites which c Development. or maintenance of electronic threaten U.S. and allied forces. Although arms countermeasures and electro-optical coun- control might prevent an expensive and poten- termeasures, which would be relatively tially destabilizing arms race in space, it would cheap, useful at all conflict levels, and un- also limit the ability of the United States to likely to be prohibited by arms control use its comparative advantage in advanced agreements. technology to protect U.S. satellites and place threatening Soviet satellites at risk. The ASAT weapon under development in the Not all arms control regimes are inconsist- United States is sufficient to meet the threat ent with ASAT development or deployment. posed by current, low-orbit Soviet military sat- “Rules of the road” for space–e.g., negotiated ellites. keep-out zones—might be pursued simultane- Should the United States decide that it is ously with ASAT research, testing, and de- in our national security interest to deploy ployment. ASAT weapons, the current MV program and, potentially, interceptors based on the recently Effective ASAT arms control would tested HOE technology, are sufficient to re- likely place significant restrictions on the spond to the threat posed by existing Soviet testing and deployment of future ballis- military satellites in low orbit. The current tic missile defense systems. U.S. ASAT could be made even more effective by the addition of a spac~based space surveil- There is considerable overlap between BMD 4Because of its usefulness, such a surveillance system would and ASAT technologies. Since even a poor bal- bean attractive target for a Soviet ASAT attack. The ultimate listic missile defense system would probably utility of such a system, therefore, hinges on its survivability. 13 lance system to aid the process of targeting altitudes out of reach of the U.S. MV. Should and/or additional basing facilities. this happen, it would provide a strong incentive to extend the MV’S capabilities by add- Many of the functions performed by Soviet ing a larger booster or to develop a newer, military satellites may eventually be per- more capable ASAT system. formed by more capable satellites orbiting at

COMPARISON OF POTENTIAL ASAT AND ARMS CONTROL REGIMES

There are widely varying views about the of A SAT and BMD technology development, wisdom of deploying weapons which are to satellite survivability, and arms control. Each operate in space or against space objects. This regime is constructed so that it is different fact, combined with more general concerns from the other regimes and so that it contains about the Soviet military threat and the elements which might reasonably be expected dangers of the U.S./Soviet arms race, has to co-exist in the same proposal. made it difficult to forge a national consensus on the subject of ASAT weapons. Some peo- 1. Existing Constraints ple oppose A SAT weapons as a matter of principle because these weapons would operate in The first regime is defined by treaties and space or because such developments would agreements presently in force; these are the contribute to the arms race. Others believe the Limited Test Ban Treaty, the Outer Space benefits of ASAT weapons are outweighed by Treaty, and the Anti-Ballistic Missile Treaty. the risk they pose to current U.S. space sys- The existing international legal regime pro- tems, which are seen as essential for maintain- hibits the use of A SAT capabilities except in ing U.S./Soviet strategic stability. Still others self-defense, the testing or deployment of see the development of A SAT and BMD weap- space-based weapons with BMD capability, ons as a means to exploit U.S. technological and the testing or deployment in space of nu- advantages to enhance U.S. power, reduce the clear space mines or ASATS that would re- threat of conflict and global nuclear war, and quire a nuclear detonation as a power source. reduce the damage done by such a war should it ever occur. Table 1-1 .—Effect of Regimes on ASAT Development In its analysis, OTA has attempted to take and Arms Control into consideration this range of viewpoints and, to the greatest extent possible, show how Restrict with Develop ASAT arms control weapons it leads to a range of policy options. Many of Existing constraints . . . . . No Yes the choices that will be made over the next sev- Comprehensive ASAT eral years will require a delicate balancing of and space-based strategic, economic, and political considera- weapon ban ...... Yes No Test ban and space- tions. There is little doubt that reasonable per- based weapon ban . . . Yes Yes/Noa sons can and will disagree as to the most One each/no new types . . Yes Yesb Rules of the road ...... Yes Yesc appropriate nature of this balance. c Space sanctuary ...... Yes Yes Seven international legal regimes and cor- Ballistic missile defense . No Yes alrr thts regime ASAT weapons could be developed, tested, and deployed on Earth responding military postures are considered but not In space The United States could pursue ASAT development with!n the critically below. Each of these regimes is in- bounds of the treaty, or it could forego ASAT development entirely bAll ASAT weapon5 other than “current types” could not be tested or cledoyed tended to facilitate assessment of the effective In space c Development and deployment optional but strongly supported by aciwcates Of ness and desirability of different combinations this regime 14

With these few exceptions, all other ASAT research could be conducted without first hav- weapon development and deployment activi- ing to modify or withdraw from the ABM ties would be allowed. It is, therefore, permis- Treaty. sible for the United States and the Soviet Some view advanced ASAT research as dan- Union to develop and deploy coorbital inter- gerous for this very reason. They argue that ceptors (like the current Soviet system), direct- such research will gradually erode the useful- ascent interceptors (like the current U.S. sys- ness of the ABM Treaty, thereby precipitat- tem), terrestrial or space-based lasers, space- ing a defensive and offensive arms competi- based neutral particle beam weapons, and tion on Earth and in space. Rather than weapons based on maneuvering spacecraft. protecting satellites, a competition in space In the current regime both the United weapons might severely reduce their military States and the Soviet Union could develop, utility. Under conditions of unrestrained com- test, deploy, and use such passive counter- petition, security might be purchased, if at all, measures as hiding, deception, evasion, only at the price of a substantial and sustained hardening, and proliferation. Active, non- commitment to the development of increas- destructive defenses, such as electronic or ingly sophisticated offensive and defensive electreoptical countermeasures, would also be space weapons. In such an environment, en- allowed. Active, destructive defenses, such as suring the survivability of satellites would re- shoot-back or DSATS, would be allowed as quire more than simple hardening or evasion. long as they did not violate any of the trea- Costly measures might have to be taken such ties enumerated above. as the deployment of precision decoys, predeployed spares, or acquiring the ability to The primary advantage of the current re- quickly reconstitute space assets. Satellites ca- gime is that it allows the almost unrestrained pable of defending themselves or a compan- application of U.S. technology to the twin ion satellite might also have to be developed problems of protecting U.S. satellites and plac- and deployed. ing threatening Soviet satellites at risk. Un- der this regime, the United States would be Should space-based weapons such as space free to use its comparative advantage in ad- mines or directed-energy weapons be deployed, vanced technology to keep pace with expected these might be capable of the almost instan- developments in Soviet ASATS and other mil- taneous destruction of a large number of crit- itary satellites. Advanced U.S. ASATS might ical satellites and ASATS. This could force na- discourage the development of more capable tions into a situation in which they must “use Soviet space systems designed to place U.S. or lose” their own pre-deployed space weap- terrestrial assets at risk. In addition, the ons. This might supply the incentive to esca- United States would be free to respond to So- late an otherwise manageable crisis. viet A SAT weapons with increasingly sophisticated defensive weapons and countermeas- 2. Comprehensive ASAT and ures, thereby reducing the probability that the Space-Based Weapon Ban Soviets would ever use their intentional or inherent ASAT capabilities. A comprehensive ASAT and spacebased weapon ban would require the United States In the existing regime, research and devel- and the Soviet Union to agree to forgo the pos- opment on new ballistic missile defense tech- session of specialized ASAT weapons, the nologies can also proceed without the con- testing—on Earth or in space—of specialized straints that might be imposed by certain ASAT capabilities, the testing in an “ASAT ASAT arms control regimes. Testing of ad- mode’ of systems (e.g., ICBMS or ABMs) vanced ASATS could provide valuable information that would contribute to the develop- ‘Testing in an “A SAT mode” would include tests of ground- ment of very capable BMD systems. There- , air-, sea- or space-based systems against targets in space or fore, some types of generic space-weapon against points in space. 15 which have inherent ASAT capabilities, and an absolute ban on possession might make it the deployment in space of any weapon. Such less likely that the current generation of a regime would require the U.S.S.R. to destroy ASAT weapons could be upgraded and held all of its coorbital interceptors and the United in readiness in significant numbers. States to destroy all of its direct-ascent inter- 6 However, if the United States can only be ceptors. confident that the Soviets are complying with Although this regime contains the most far- a treaty to the extent we can verify compli- -reaching arms control provisions, it would ance, then the United States would not have have the disadvantage of being the most dif- confidence that this regime offered any greater ficult to verify. Unlike an ASAT test ban and protection to our satellites than would a test space-based weapons ban regime, a compre- ban and space deployment ban. hensive ban would prohibit possession and testing of A SAT weapons on Earth.7 Because 3. ASAT Weapon Test Ban and the current Soviet coorbital interceptor is a Space-Based Weapon Deployment Ban relatively small spacecraft launched on a much larger, generaI-purpose booster, the Soviet In this regime, in addition to adhering to Union could maintain and perhaps even ex- treaties and agreements presently in force, the pand its ASAT force without the the United Soviet Union and the United States would States gaining unambiguous evidence of a vio- agree to forgo all testing in an “A SAT mode” lation. and the deployment of any weapon in space. Such a ban would not only prohibit the test- Since the United States might agree to a ing of both current and future ASAT systems comprehensive ASAT ban only after consid- but would also place similar restrictions on erable domestic political friction over ques- BMD systems with ASAT capabilities. This tions of compliance and verification, it is im- regime would not ban terrestrial research on portant to consider how such a ban might ASAT or space-based weapons and would not make a greater contribution to U.S. national attempt to ban their possession. Therefore, if security than a ban on ASAT testing and it were judged to be desirable, ASAT and spacebased weapon deployment (discussed be BMD weapons could be developed (though not low). The purpose of both bans would be to pre tested in space) and held in readiness on Earth. vent the use of ASATS, or, at minimum, to reduce the probability that an ASAT attack In a test ban regime, the passive counter- would be effective. An ASAT test ban would measures and nondestructive active counter- primarily affect weapons reliability, while an measures that were discussed in the “existing ASAT possession ban, if observed, would af- regime” could still be developed and employed. fect both availability and reliability. It is con- Destructive active countermeasures such as ceivable that the risk posed by possible ille- “shoot-back” or DSATS could not be tested gal Soviet use of ASAT weapons might be or deployed but could be developed and held somewhat lower in a regime in which the in readiness. Soviets could not lawfully possess ASAT Although a ban on testing in an “ASAT weapons. Presumably, the inability to overtly mode” would not eliminate all threats to sat- possess ASAT weapons would diminish one’s ellites, it would reduce the cost and complex- ability to use them effectively. Furthermore, ity of ensuring a reasonable level of satellite survivability. The United States would still 6Such an agreement might resemble the draft treaty proposed benefit from ‘hardening’ its satellites and de- to the United Nations by athe U.S.S.R. in August of 1983, except that draft also bans the testing or use of manned space- ploying spares and decoys, but the more craft for military purposes. See U.N. Document A138/194, Aug. elaborate, expensive, precaution of developing 23, 1983. and deploying DSATS would be prohibited 7A comprehensive ban would not ban systems with inherent ASAT capabilities, such as ICBMS, ABMs, and maneuvera- and, indeed, less attractive. In the absence of ble spacecraft, reliable, effective ASATS, satellites would pre 16 -.

Table l-2.—Sensor Technology for Compliance Monitoring

Prohibitable action Observable .— sensors ASAT attack: Attack sensors: KEWa impact ...... acceleration accelerometers Pulsed HELb irradiation . . . acceleration accelerometers Continuous H EL irradiation ...... heating thermistors NPBC irradiation ...... ionization ionization detectors Keep-out zone penetration . . . position of thermal radiation source (ASAT) space-based LWIRd thermal image~ f Interception test ...... positions of thermal radiation sources space-based LWIR thermal imageP r (ASAT and target) NPB ASAT operation ...... thermal radiation from ASAT space-based LWIR thermal imagere HEL ASAT operation ...... thermal radiation from ASAT space-based LWIR thermal image~ f Irradiation of target with NPB ...... gamma radiation from target gamma-ray spectrometer Irradiation of target with pulsed HEL ...... thermal radiation from target space-based LWIR thermal imager Irradiation of target with pulsed HEL ...... reflected radiation from target space-based multi spectral imager Irradiation of target with continuous HEL ...... position of thermal radiation source (target) space-based LWIR thermal imager Irradiation of target with continuous HEL ...... reflected radiation from target space-based multi spectral imager Nuclear explosive aboard satellite ...... gamma radiation from fissile or fusile gamma-ray spectrometer (and optional nuclei activated by cosmic radiation or by particle beam generator) particle — beams a/([email protected] weapon bHtgh.energy laser cNeutral. Darticle beam dl-ong.w~velength Infrared eThe LWlR telescope on the Infrared A~trOnOnll~al satellite (lRAs) OXOMpliflOS demonstrated space-based tflerrnal IMager technology, this Instrument IS described in .4strophys/ca/ Journal, 278 (1, Pt. 2), L1 -L85, Mar 1, 1984 (Spectal Issue on the Infrared Ast ronomlcal Satelllte) fRadar and Passive radio direction.finding methods could also be useful for tracking, tf h!dlng measures are not employed b the Penetratln9 spacecraft LWIR tracking IS emphasized here because it is difficult to counter by such measures gA target irradiated by a high-energy neutral panicle beam will emit gamma rays, neutrons, and other observable particles, Just as It Will, at a slower rate, when bombarded by natural cosmic rays These gamma rays could be detected by a gamma-ray spectrometer such as those which have been carried by Sowet Venusian and lunar landers and by U S NASA Ranger and Apollo spacecraft (NASA report SP-387, pp 3.20 ) sumably be of greater utility since the United on the HOE technology) since a “no test” ban States might have higher confidence that they would not prohibit ASAT possession. How- would be available when needed. ever, confidence in the operational capability of both the U.S. and Soviet ASAT systems Relative to the existing regime, the primary would degrade over time without continued advantage of a regime banning testing of operational testing. ASAT capabilities and deployment of space- based weapons would be that highly valued There would be two important disadvan- U.S. satellites in higher orbits–e.g., the future tages to this regime. First a ban on testing in MILSTAR system–could be protected with an “A SAT mode” and deploying space-based some confidence from advanced A SAT weap- weapons would not offer absolute protection ons, especially if protected as well by passive for satellites; there would remain some possi- countermeasures. The fact that advanced bility that an untested–or covertly tested– ASATS could not be overtly tested would re- advanced ASAT, if suddenly deployed and duce the probability that they would be devel- used, might actually work well enough to over- oped and deployed. If they were developed and come passive countermeasures. Second, with- used without prior testing, a test ban would out an ASAT weapon the United States would reduce the probability that they would be suc- lack a fully tested means to attack threaten- cessful. ing satellites. The United States would, therefore, have to place greater reliance on coun- As in the existing regime, the United States termeasures to protect its terrestrial assets. could retain a capability to attempt to negate It is unclear whether countermeasures alone low-altitude Soviet satellites with its MV will be able to keep pace with the threat posed ASAT (or, possibly, with interceptors based by advances in military satellites. 17

Depending on one’s viewpoint, an additional A primary disadvantage of a “no new advantage or disadvantage of this regime is types” regime would be that allowed (i.e., that the testing of some types of advanced tested, nonnuclear) U.S. ASAT weapons would BMD weapons would be prohibited. This probe inadequate to negate threatening Soviet hibition might even include some ground- satellites if such satellites were moved to based BMD weapons such as the U.S. HOE higher orbits–a feasible but technologically (Homing Overlay Experiment) ABM intercep- difficult and costly Soviet countermeasure. An tor, which is currently allowed under the ABM additional disadvantage to this regime is that Treaty. Although such limitations would only attempts to define “new types” of ASATS be slightly more restrictive than those of the would be likely to result in the same ambiguity ABM Treaty, they would be very restrictive and distrust that resulted from attempts to when compared to a regime in which the ABM define “new types” of ICBMS in the SALT II Treaty was no longer in force. negotiations. Finally, the degree of protection afforded high-altitude satellites by a ban on testing “new types” would be uncertain; there 4. One Each/No New Types would remain some probability that an un- Regime four would include arms limitation tested advanced ASAT, if suddenly deployed provisions which would restrict the United and used, might actually work. Systems with States and the Soviet Union to their current inherent ASAT capabilities (ICBMS, ABMs, ASATS and prohibit the testing in an “A SAT maneuvering spacecraft) would also still exist. mode’ and deployment, in space, of more ad- As in the test ban and space-based weapon vanced systems. Existing treaties and agree- ban regime, a “no new types’ regime would ments would remain in force. In addition to limit the testing of some types of advanced banning the testing or deployment in space of BMD weapons which are currently allowed un- new types of ASATS, the “no new types” der the ABM Treaty. agreement would prohibit making current systems more capable so they could attack tar- 5. “Rules of the Road” for Space gets at higher altitudes. BMD systems would also be banned if they had ASAT capabilities. Whether or not the United States and the In a “no new types” regime, the passive Soviet Union agree to restrict ASAT weapons, countermeasures and nondestructive active they might negotiate a set of “rules of the road” for space operations. These rules could countermeasures that were discussed in the “existing regime” could still be developed and serve the general purpose of reducing suspi- employed. Destructive active countermeas- cion and encouraging the orderly use of space, or they could be designed specifically to aid ures such as “shoot-back” or DSATS could not in the defense of space assets. Examples of be tested or deployed but could be developed and held in readiness. Current ASATs—should general rules might include agreed limits on they already possess the capability when the minimum separation distance between satel- treaty is signed-could be used to attack other lites or restrictions on very low-altitude over- ASATS. flight by manned or unmanned spacecraft. These general rules might also be used to The primary advantage of a “no new types” establish new, stringent requirements for ad- regime, relative to the existing regime, would vance notice of launch activities. Specific rules be that, by prohibiting the testing of advanced for space defense might include agreed and A SAT weapons, highly valued U.S. satellites possibly defended “keep-out zones, ” grants or in higher orbits could be protected with some restrictions on the rights of inspection, and confidence. In addition, the United States limitations on high-velocity fly-bys or trailing could retain a capability to negate low-altitude of foreign satellites. It might also be desira- Soviet satellites (e.g., RORSAT) in the event ble to establish a means by which to obtain of war and to respond in kind to a Soviet timely information and consult concerning am- ASAT attack. biguous or threatening activities. 18

The “rules of the road” discussed above– There are too many satellites in low-Earth if implemented in the absence of restrictions orbit to accommodate large keep-out zones. on ASAT weapon development—would not re- However, it might be feasible to establish move the threat of ASAT attack. The primary smaller keep-out zones around such satellites purpose of such a regime would not be to re- and, in addition, to specify a minimum angu- strict substantially the activities of the par- lar separation between orbital planes to pre- ties, but rather, to make the intentions behind vent continuous trailing. these activities more transparent. Although the degree of protection for U.S. space assets 6. Space Sanctuary to be gained from a “rules of the road” agreement would be less than from other arms limi- Regime six would establish altitude limits tation regimes, the costs would also be cor- above which military satellites could operate respondingly less if other nations failed to but where the testing or deployment of weap- comply with such rules. One must assume that ons would be forbidden. A “space sanctuary” in the absence of ASAT arms control, both regime would not constrain ASAT weapon de- ASAT development and satellite survivabil- velopment, testing, or deployment in space ity programs will be given high priority. This but would attempt to enhance security by pro- being the case, offensive and defensive meas- hibiting these activities in deep space (i.e., ures would be available to respond to viola- above 3,000 nautical miles, or about 5,600 tions of “rules of the road. ” kilometers) where critical strategic satellites are based. At present, the altitude of these If they were defended, “keep-out zones” strategic satellites makes them invulnerable to would probably offer the closest thing to secu- attack by the current Soviet and U.S. ASATS. rity in a “rules of the road” regime. Space mines designed to shadow satellites and det- In a “space sanctuary” regime, the passive onate on command would lose a great deal of countermeasures and nondestructive active their utility if held at bay by a defended keep- countermeasures that were discussed in the out zone. Nonetheless, there are a number of “existing regime” could still be developed and difficulties with trying to implement this re- employed. Unlike the “test ban” or “no new gime, not the least of which would be the re- types” regime, destructive, active counter- action of other space-faring nations. measures such as DSATS could be tested and deployed, but not in deep space. Deployment ASAT weapons such as nuclear interceptors in deep space of ‘‘shoot-back’ capabilities or must be kept at a range of several hundred DSATS would probably be prohibited since it kilometers from moderately hardened satel- might be impossible to differentiate these lites in order to protect such satellites; ad- weapons from offensive ASATS. vanced directed-energy ASAT weapons might have to be kept much farther away. Given the The primary advantage of this regime would number of satellites currently in orbit, this be that it could protect satellites in high or- would present several problems. Satellites in bits from the current generation of ASAT geostationary orbit are already so closely weapons. In addition, a deep-space sanctuary spaced that a keep-out zone sufficiently large regime would constrain ASAT development to protect satellites from a nuclear weapon less than would a comprehensive test ban re- would displace other satellites. It is possible gime or a no-new-types regime. However, that critical strategic warning and communi- should the United States and the Soviet Un- cations satellites could function in supersyn- ion choose to pursue advanced ASAT weap- chronous orbits.8 If so, there would be ade- ons, a space sanctuary might offer only limited quate room to accommodate large keep-out protection. zones around satellites in such orbits. The greatest risks in a space sanctuary regime would be posed by advanced directed- ‘I.e. higher than geosynchronous orbital altitude. energy weapons which could be tested and de- . 19 ployed at low altitudes. Such testing and deployment would probably be adequate to guar- 7. Space-Based BMD antee effectiveness against targets at higher The seventh regime might result from U.S. altitudes. Satellites at very high, supersyn- or Soviet withdrawal fro-m the ABM Treaty chronous altitudes might still derive some pro- followed by the deployment of space-based tection from this regime, but violation of the BMD systems. Since even a modest BMD sys- sanctuary by highly maneuverable kinetic- tem would make a very capable A SAT weap- energy weapons or by satellites covertly car- on, in a “space-based BMD” regime there rying powerful nuclear or directed-energy could be no attempt to restrain ASAT devel- weapons would remain a risk. For this reason, opment. Moreover, each side would probably sanctuaries might provide less security than want the freedom to develop new A SAT weap- would keep-out zones (discussed above), be- ons capable of destroying the opponent’s cause any foreign satellite entering an agreed space-based BMD systems. keep-out zone could be fired upon, while a satellite entering a sanctuary could be lawfully The ASAT weapons allowable under the fired upon only if it could be proven that it “spacebased BMD” regime would include all was, or carried, a weapon. of those in the “existing regime, plus weap-

Artist’s conception of the Space Shuttle deploying a neutral particle beam weapon.

Neither of the weapons I Illustrated here exwts today, but I n the absence of agreed limitations, both the United States and the Soviet Union WI I I probably develop a wide range of advanced space weapons. 20 ons capable of countering ballistic missiles in ASAT countermeasures must prove to be ef- flight. Defensive measures would be less con- fective for spacebased BMD platforms if a de- strained and more essential than in the “ex- cision to deploy them is to make sense. Per- isting regime. In particular, advanced space- haps large improvements in the effectiveness based weapons such as neutral particle beam or economy of passive countermeasures such weapons could be deployed at low altitudes as combinations of hardening, deception, and and then used as ASAT or DSAT weapons. proliferation would provide the needed protec- Passive countermeasures and nondestructive tion. Alternatively, the superior fire-power or active countermeasures like those discussed massive shielding of BMD weapons might in the “existing regime” would be developed give them a degree of protection unattainable and employed. by smaller, less capable satellites. Depending on one’s viewpoint, the principal With respect to other military satellites, the advantage, or disadvantage, of a space-based expense of equipping them with countermeas- BMD regime would be that it would allow the ures to insure some level of survivability United States and the Soviet Union to deploy against advanced BMD systems would be con- highly capable weapons in space. On March siderable. However if, as some argue, space- 23, 1983, President Reagan called for a vigor- based missile defenses could make us more se- ous research program to determine the feasi- cure and encourage the Soviets to make real bility of advanced BMD systems, suggesting reductions in offensive missiles, this would re- that the deployment of such systems, if fea- duce the threat of U.S./Soviet conflict. In a sible, could offer an alternative to the current world where conflict was less likely, satellite stalemate in strategic nuclear weapons. Given vulnerability would be less important. the inherent ASAT capabilities of advanced Others, of course, disagree strongly with BMD weapons, satellites would be most vul- this argument. They claim that space-based nerable in a space-based BMD regime. Before missile defenses will decrease our security by the United States deployed space-based BMD systems it would have to determine, first, that encouraging greater competition in both offensive and defensive weapons. In a world of the contribution that such systems made to space-based weapons and higher U.S./Soviet U.S. security was great enough to compensate tension, satellite vulnerability would be a crit- for the threat which similar opposing systems ical and potentially destabilizing factor. would pose to U.S. satellites; and, second, that space-based BMD components could be protected at competitive cost against advanced ASAT weapons.

TREATIES OF LIMITED DURATION Each of the regimes examined above could tions for the indefinite future.g Treaties of be negotiated as a treaty of indefinite or limited duration allow parties to take advan- limited duration or, alternatively, as one which tage of future technological options, yet can remained in force as long as periodic reviews were favorable. Each of these alternatives Wheaties of unlimited duration usually contain a clause which would have its advantages and disadvantages. states that if a country’s “supreme national interests” are threatened, then that country may withdraw from the treaty, Treaties of indefinite duration are more effec- In addition to “supreme national interest clauses, ” treaties may tive at discouraging the pursuit of banned also contain specific unilateral or agreed statements regarding activities, yet require a greater degree of fore- specific understandings about related events. For example, The 1972 ABM Treaty contains a unilateral statement by the LJnited sight regarding the long-term interests of the States which links the continued viability of the treaty to “more signatories and can foreclose technological op- complete limitations on strategic arms. ” 21 encourage aggressive development programs tinued in force after they had expired (e.g., the designed to reach fruition at the termination “Interim Offensive Agreement” signed at of the designated period. Treaties which call SALT I). The real issue would be whether the for a periodic reassessment of agreed limita- parties believe that adherence to the treaty in tions in theory have great flexibility, yet, in question continued to be in their national secu- practice, often result in a strong presumption rity interest. that they should be continued. The Reagan Administration has recently in- The United States might, for example, en- dicated that it intends to conduct ASAT tests ter into a treaty limiting ASATS with the ex- to gather information useful in advanced plicit and public reservation that we would BMD research.l” Given the close connection withdraw from this treaty if and when we were between these two technologies, an ASAT ready to test and deploy a ballistic missile de- treaty of even limited duration would require fense system in ways that the ASAT Treaty modification of current SD I program plans. would forbid. Alternatively, we might take the Thus, to the extent that the United States public position that we intended to restrict our wished to maintain the most rapid pace of ad- BMD activities so as to remain within the vanced BMD research within the bounds of limits of an ASAT Treaty. While the former the ABM Treaty, such a treaty would not be position would suggest a treaty of limited du- desirable. Conversely, to the extent that the ration and the latter a treaty of unlimited du- United States wished to slow the pace of So- ration, this need not be the case. It would be viet BMD research and would be willing to de perfectly possible to sign a treaty of unlimited fer decisions regarding the testing of space- duration, with the standard provision allow- based or space-directed weapons, an ASAT ing for withdrawal, accompanied by a clear treaty of limited duration could contribute to statement of some of the conditions under that result. which we intended to withdraw.

- From one point of view, the exact language jOThe ~urpo9e of ~9t9 ‘ ‘in an ASAT mode’ would be to in in a treaty regarding its duration would be less vestigate advanced technologies without violating the ABM Treaty. The Department of Defense recently told Congress that, important than the intentions of the parties. “To ensure compliance with the ABM Treaty the performance After all, there have been numerous examples of the demonstration hardware will be limited to the satellite of treaties of unlimited duration that were vio- defense mission. Intercepts of certain orbital targets simulating anti-satellite weapons can cleady be compatible with this lated soon after they were signed and exam- criteria. ” [Report to the Congress on the Strate@”c Defense Im”- ples of treaties of limited duration that con- tiative, Department of Defense, 1985, app. B, p. 8.] Chapter 2 Introduction Contents

Page overview ...... 25 Space Weapons: Attitudes and Controversy ...... 26 ASATs and BMD ...... 26 Attitudes Toward the Military Uses of Space ...... 26 Organization of the Report ...... 28 Chapter 2 Introduction

OVERVIEW

This report examines the issues raised by the ● the implications of anti-satellite weapons development of weapons capable of attacking and space-based or space-directed missile objects stationed in space. It analyzes the mili- defense concepts for standing arms control tary utility of space systems, describes the tech- agreements, particularly the Anti-Ballistic nical characteristics and military value of anti- Missile, Outer Space, and Limited Test Ban satellite (ASAT) weapons, and discusses the ef- Treaties;s and fectiveness of a number of satellite defenses and ● the prospects for future space-related arms technical countermeasures. Finally, the report control agreements, including an assess- examines how various levels of ASAT arms con- ment of advantages, disadvantages, and trol might contribute to U.S. national security verifiability e when combined with various survivability meas- The subject of ballistic missile defense ures and various levels of ASAT development (BMD)–particularly space-based BMD–was of and deployment. special interest to both the House Armed Serv- Believing that the development of weapons ca- ices and Senate Foreign Relations Committees. pable of attacking missiles in flight or objects This subject is dealt within a companion OTA in space would likely have a strong effect on “de- report, Ballistic Missile Defense Technologies. terrence, crisis stability, arms control and. . . na- There is a strong relationship between ASAT tional security policy, ” the House Committee on and BMD technologies and the technical, polit- Armed Services’ and the Senate Committee on ical, and diplomatic actions taken in one sphere Foreign Relations’ asked the Office of Technol- will almost certainly affect the other. For this ogy Assessment to prepare this report. The com- reason, OTA assessed the two subjects at the mittees requested that the report should, among same time, with a single staff, and with the ad- other things, assess: vice of a single advisory panel. In each of these the feasibility, effectiveness, and cost of va- reports, OTA has endeavored to make clear the rious space-based or space-directed relationship between these two sets of technol- concepts; 3 ogies, and where appropriate has provided cross- the relationship between capabilities that -references to further assist the reader. can reasonably be expected and the impact In producing this unclassified report, OTA of the technology exploitation effort on the was able to draw on a wide range of classified overall strategic policy of the United 4 material. Appendices of classified notes on this States; report are available to individuals having appro- ‘Letter from Melvin Price, Chairman, William L. Dickinson, priate security clearances and who require ac- Ranking Minority Member, and Les Aspin of the House Armed cess to that material. Services Committee, to John H. Gibbons, Director, Office of Technology Assessment, Mar. 5, 1984. ‘Letter from Charles H. Percy, Chairman, Claiborne Pen, Ranking Member, Larry Pressler, and Paul E. Tsongas of the Senate Foreign Relations Committee to John H. Gibbons, Di- rector, Office of Technology Assessment, Mar. 20, 1984. ‘Ibid. ‘Supra, note 2. 4Supra, note 1. ‘Ibid.

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SPACE WEAPONS: ATTITUDES AND CONTROVERSY Assuming that highly capable and militarily broader context of this country’s reassessment useful ASAT weapons can be built at an accept- of its strategic posture and the military util- able cost, then why not proceed with develop- ity of space. ment and deployment? Why should the U.S. Congress give more attention to ASATS than Attitudes Toward the it gives to other new terrestrial weapon systems Military Uses of Space (e.g., anti-ship or anti-aircraft weapons)? In addition to understanding the complex ASATS and BMD relationship between ASAT and BMD technologies, one must also recognize that people Going forward with ASAT weapon develop- think about the military use of space in radi- ment or, alternatively, agreeing to restrict cally different ways. There are a great many such development through arms control meas- views—both pro and con—regarding weapons ures, could have important consequences for that would operate in or from space; it is use- advanced, space-based BMD technologies. ful to examine several of the more frequently Over the past several years a major debate on stated positions.7 strategic defense has been taking place in the United States. Some believe that ballistic mis- Opposition to Space Weapons sile defenses can be developed that may even- Some people oppose the development of tually allow the United States to abandon the weapons that would operate in or from space current policy of deterrence through assured because they feel such activities run counter retaliation. Others believe that even increased to the legal and political history of space. They research on BMD alternatives might precipi- point to the many examples of successful in- tate an offensive arms race with each side ternational cooperation in space science, hastening to counter possible defenses with commerce, law, and politics and see these more and better offensive arms. This debate activities as reducing international tension was intensified by President Reagan’s March and contributing broadly to peace and devel- 23, 1983, speech which outlined what was later opment. Space weapons are seen as violating to become the Strategic Defense Initiative. the spirit and, in some cases, the letter of the Since the debate over ballistic missile de- treaties and agreements to which the United fense involves a fundamental reassessment of States is a party. They point to the language this country’s strategic policy, decisionmakers of the 1967 Outer Space Treaty, which states are reluctant to proceed with ASAT weapon that space activities should be conducted “in development, deployment, or arms control de the interest of maintainingg international peace cisions that may tie their hands with respect and security and promoting international co- to future technologies or that may commit operation and understanding. ”8 Adherents of them irrevocably to a course with unforeseen this viewpoint emphasize that every Ameri- consequences. Some people believe that ASAT can President since Eisenhower has stated weapon development programs will be used to accomplish BMD research, thereby avoiding ‘For a discussion of various “space doctrines, ” see: “Space the strictures of the ABM Treaty and the scru- Doctrines, ” Lt. Col. D. Lupton, USAF (Ret.), Strt.ite~”c Rew”ew, tiny of Congress. Others believe that ASAT fall 1983, pp. 36-47; see also: Lt. Col. D. Lupton, USAF (Ret.), On Space Warfare: A SpacePower Doctrine, U.S. Air Force, Air arms control restrictions would impede future University Command, center for Aerospace Doctrine, Research, BMD research and development programs. and Education, Maxwell Air Force Base, Alabama, 1985. Given these opposing viewpoints, the decision “’Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon to go forward with or, alternatively, to restrict and Other Celestial Bodies, ” 18 U.S.T. 2410, T. I.A. S. 6347, Ar- ASAT development must be made in the ticle III. 27 support for the idea that space should not be war might occur either through accident or in- an arena of conflict and that space exploration tention. At present, nations can use space to should contribute to peace. The web of com- peer within the boundaries of other sovereign mitments that the United States has fash- states to obtain otherwise inaccessible in- ioned over the past 25 years through its agree formation and early warning of attack. For ments and unilateral declarations is seen as this reason, many believe that space is of imposing a positive burden on the United greater value to the United States than to the States to support the broad ideals stated in Soviet Union, since the Soviet Union has other the Outer Space Treaty. means of gathering information in the open Others–although acknowledging the impor- U.S. society. Adherents to this position main- tance of the laws and the history of space— tain that, though there are many potential military uses of space, the communication and base their opposition to space weapons on the belief that the deployment of such weapons in information-gathering activities are the most space, if not halted now, will be impossible to important. They argue that these benefits will reverse. Since neither the United States nor be jeopardized by U.S./Soviet military space the Soviet Union now has weapons that are activities such as ASAT weapons develop- based in space, they feel that it is both possi- ment or space-based BMD. Although these ble and desirable to prevent the arms race latter activities also have military utility, they from extending to this new environment. This are not seen as outweighing the risk that such view is widely held in countries other than the systems would create. United States and the Soviet Union. Over the Support for Space Weapons last several years, the Soviet Union has made a strong effort to place the blame for the Those who support the development of militarization of space on the United States. weapons that would operate in or from space The American point of view is that the arms generally emphasize the importance of being race is a burden imposed on the United States able to exert military power in space. Some by the inordinate military preparations of the supporters view space as merely another Soviet Union. Nonetheless, many nonallied sphere of military activity; others feel that mil- governments, as well as important segments itary space activities might offer a means by of the populations of even our allies, view the which to fundamentally alter the U.S./Soviet superpower arms race as a dangerous and de- strategic balance. Advocates of the former stabilizing activity.g Those who see the super- viewpoint emphasize that the increase in the power arms race as a dangerous process which number of Soviet military space systems with the protagonists are doing little to halt are enhanced capabilities creates a threat to which likely to see military development in space as the the United States must be prepared to re- an integral part of that process. spond. In particular, supporters of this position stress the importance of being able to de- Some opposition to space weapons derives stroy satellites which assist the Soviets in from the fact that such weapons would place targeting U.S. terrestrial forces. They believe at risk critical communication and informa- that in order to deter or, alternatively, to pre- tion-gathering satellites that contribute to the vail in terrestrial conflicts, the United States stability of the U.S./Soviet relationship.l” must be able to operate in, and respond to Space weapons are seen as destabilizing and threats from, space just as it does on land, at likely to increase the possibility that a nuclear sea, or in the air.11 ‘U.S. Congress, Office of Technology Assessment, Um”space ’82: A Context for Cooperation and Competition-A Technical 1lColin Gray, “Why an ASAT Treaty Is a Bad Idea, ” Aero Memorandum, OTA-TM-ISC-26 (Washington, DC: U.S. Gov- space Amen”ca, April 1984, pp. 70 ff.; and R. F. Futrell, ideas, ernment Printing Office, March 1983). Concepts, and Doctrine: A Histoqy of Basic Thinking in the ‘“see: R. Garwin, K. Gottfried, and D. Hafner, “Anti-Satellite United Stabs &r Force, 1907-1964, U.S. Air Force, Air Univer- Weapons, ” Scientific American, vol. 250, No. 6, June 1984, pp. sity Command, Maxwell Air Force Base, Alabama, 1974, pp. 45 ff. 279-282, summ arizing views of Gen. Thomaa D. White, USAF. 28

Some space weapons advocates see space as weapons would operate in space, others oppose more than just another theater of military ASAT weapons because they believe the ben- operation; they see it as a solution to the cur- efits of such weapons are outweighed by the rent stalemate in offensive nuclear weapons. risk they pose to current U.S. space systems. They argue that space-based ballistic missile Some people support ASAT weapons simply defenses can provide the opportunity for the because they feel the United States must be United States to abandon its current doctrine able to respond to Soviet threats from any the of assured retaliation. Should both the United ater. Other supporters see space as a means States and the Soviet Union possess space- to project U.S. power, reduce the threat of con- based defensive forces, then more desirable flict and global nuclear war, and reduce the offensive-defensive or purely defensive strat- damage done by such a war should it ever occur. egies can be developed. Other space power ad- In its analysis, OTA has attempted to take vocates see space weapons as a means to cap- 2 into consideration this range of viewpoints ture the “high ground. ”1 The current U.S. and, to the greatest extent possible, show it lead in military space technology is seen as leads to a variety of policy options. As this re granting a military advantage over the Soviet port demonstrates, the opportunities and risks Union-an advantage which, if not seized, will that might result from developing or not de- soon be lost. veloping ASAT weapons or from pursuing or Because views about the military uses of not pursuing ASAT arms control cannot be space vary so widely, it has been difficult to simply stated. Many of the choices that will forge a national consensus on the subject of be made over the next several years will re- ASAT weapons. Some people oppose ASAT quire a delicate balancing of strategic, eco- weapons as a matter of principle because these nomic, and political interests. There is little doubt that reasonable persons can and will dis- ‘zLt. Gen. Daniel O. Graham, USA (Ret.), High Fronti”er: A Strategy for IVational Survival (Washington, DC: High Fron- agree as to the most appropriate nature of this tier, 1983). balance.

ORGANIZATION OF THE REPORT The main body of this report begins with the available to the United States to counter or discussion in chapter 3 of the military utility compensate for Soviet ASAT capabilities. of satellites and ASAT weapons. This chapter provides the conceptual framework neces- Chapter 5 reviews the history of arms con- sary to understand how these various space trol related to ASAT weapons. This chapter systems contribute to or threaten U.S. na- describes the constraints imposed by treaties tional security. Current and projected Soviet and agreements in force and discusses the in- and U.S. military satellite capabilities are ex- ternational political barriers to ASAT devel- amined, as are a variety of responses to such opment. The 1978-79 ASAT negotiations be- capabilities. tween the United States and the Soviet Union are examined, along with subsequent draft Chapter 4 provides a detailed technical look treaties proposed by the Soviet Union. Recent at the existing and projected ASAT capabil- legislative and executive branch activities are ities of the United States and the Soviet also summarized. Union. This chapter discusses both existing technologies and the possibilities for more ad- Chapter 6 describes a number of different vanced kinetic-energy, nuclear, and directed- ASAT arms control provisions that might be energy ASAT weapons. It also considers the sought by the United States. Restrictions on wide range of technical and political responses testing, possession, deployment, and use are 29 all examined to determine whether they might of technical measures and countermeasures contribute to U.S. national security. Provi- discussed in chapter 4 with examples of arms sions restricting spacecraft operation and control as discussed in chapter 6. Each of orbits—so-called “rules of the road’ ’—are also these hypothetical regimes describes the ad- examined. vantages and disadvantages of different combinations of ASAT weapons development, em- Finally, chapter 7 provides a comparative ployment policies, defensive countermeasures, evaluation of seven hypothetical legal/techni- and arms control. cal regimes. Each regime combines examples Chapter 3 MILSATS, ASATS, and National Security Contents

Page The Role and Value of Military Satellites ...... 33 The Role of Military Satellites...... 33 Current and Projected MILSAT Capabilities ...... 35 Possible Advanced-Technology MILSAT Capabilities ...... 39 The Value of Military Satellites ...... ~ ...... 40 The Vulnerability and Protection of Military Space Systems ...... 43 The Role and Value of Anti-Satellite Capabilities ...... 44 Military Space Policy...... 45 Military Space Policy Issues ...... 45 ASAT Policy Issues ...... 45 Ballistic Missile Defense as an ASAT Policy Issue ...... ~ 46

Tables Table No. Page 3-l. Asymmetries in U.S. and Soviet Space System Need and Use ...... 34 3-2. Orbits of Some Soviet Military Satellites ...... ~ ...... 37 3-3. Possible Responses to Enemy MILSAT Capabilities ...... 45

Figures Figure No, Page 3-1. Ground Track of Soviet Radar Ocean Reconnaissance Satellite ...... 37 3-2. Radar Imagery From Kosmos 1500 ...... 38 3-3. Imagery Obtained by Synthetic-Aperture Satellite Radar ...... 40 Chapter 3 MILSATs, ASATs, and National Security

THE ROLE AND VALUE OF MILITARY SATELLITES

The Role of Military Satellites speed of communications may make the differ- Force Support and Force Enhancement ence between winning a battle and losing one—or it may greatly affect the number of Satellites are used for a variety of military casualties suffered in a battle without decid- applications by the United states, the U. S. S. R., ing victory. In some cases satellites provide and-in smaller numbers—by several other na- capabilities that could not be obtained in any tions. Most military satellites (MILSATs) per- other way —e.g., surveillance of areas which form nondestructive functions. For example, would otherwise be closed to our observation, Soviet military satellites are used for meteoro- or providing very early warning of enemy mis- logical surveillance, surveillance of ballistic sile launches. In other cases, satellites provide missile launch areas to provide rapid warning a cheaper and easier way of of doing some- of possible missile attack, relaying of radio thing that could be accomplished by other communications to distant force elements, op- means-e. g., trans-Atlantic communications. tical and radar reconnaissance of foreign force Then there are the navigation satellites, which dispositions on land and at sea, interception provide an added degree of precision which of foreign radio communications and radar sig- may be critical in some applications and only nals, transmission of radionavigation signals, of marginal utility in others. and logistic support for space systems.1 Even though these functions are nondestructive and In a few special cases, satellites contribute the satellites which perform them are not con- to a military mission the objectives or require- sidered weapons, they support force elements ments of which can be quantified, as can, which would engage in direct combat and en- therefore, the value of the support provided hance the combat effectiveness of those force by satellites. For example, the use of naviga- elements. tion satellites may improve the accuracy with which certain munitions are delivered, thereby The value, or utility, of military satellites is reducing wastage of munitions. If so, then the very real, but it is extremely difficult to quan- 2 effectiveness of the munitions used would be tify. The timeliness of information or the “multiplied” by satellite support—they would ‘E.g., maintenance and retrieval. be as effective as a larger number of munitions *The term utih”ty is used here in the sense defined by John delivered without the assistance of navigation von Neumann and Oskar Morgenstern, The Theory of Games and Econom”c Behavior (Princeton, NJ: Princeton University satellites. The effectiveness of munitions de- Press, 1953), pp. 26-27; i.e., as a numerical index of the rela- livery systems would be similarly multiplied. tive preferability of an outcome [e.g., occurrence of nonnuclear For missions such as this, it is reasonable to war and survival of all high-altitude satellites] which could re- think of satellites as “force multipliers, ” and sult from a decision [e.g., an agreement to ban ASAT weapon testing]. Of any two possible outcomes, the one having a higher the factor by which the forces are multiplied utility would be preferred over the other. Practical methods of can in principle be used to assess the value of assessing the utilities of a decisionmaker for possible outcomes the satellite. This has led some analysts to as- have been described and reviewed by M.W. Merkhofer, Com- parative Evaluation of Quantitative Decision-Making Ap- sess the significance of anti-satellite weapons proaches, National Science Foundation report NSF/PRA-83014, in terms of the additional forces which the April 1983. Other notions of utility have been used in the classified liter- United States would have to procure to main- ature on satellite utility. Some of these notions are vaguely de- tain military capability if it could not use fined, while others-e. g., force multiplication factors—are pre- MILSATs–or could not rely on their avail- cisely defined and, in principle, objectively calculable, although less clearly related to national interests than are Von Neumann- ability—in a conflict severe enough to justify Morgenstern utilities. Soviet ASAT use.

33 34

However, in assessing the importance of multiplication of particular types of force ele- ASATS, it maybe more important to consider ments has been estimated in several studies.e the dependence of military capabilities on Insofar as such estimates are comparable, space systems. If space system support sud- judgments of comparative space support dif- denly becomes unavailable to a force element fer. Such differences may attributable, in part, which has become accustomed to it, the com- to exclusion from the scope of some studies, bat effectiveness of that force element maybe for reasons of security classification, of con- reduced to lower than it was before it began sideration of some types of satellites which are using space system support. Its effectiveness of great value to the United States but for will be reduced to a fraction of what it was which the U.S.S.R. has no counterpart or from with space system support; the smaller this which the U.S.S.R. might derive much less fraction, the greater the force element’s de- utility. The utility of some functions of such pendence on space support. satellites may be unquantifiable in any case, and this may lead to their neglect in quantita- There is a trend in both the United States tive assessments of utility. and the U.S.S.R. to use increasingly sophisticated satellites to perform more functions and It is easier to argue that the United States to do so more capably. It is generally believed is more dependent on space system support that because of its sophisticated and still ad- for performing important military functions vancing space technology and because of the than is the Soviet Union,7 because the Soviet global distribution of its interests, commit- Union has less need for some types of space ments, and forces, the United States derives system support and more alternative terres- considerable utility from space system sup- trial means of providing similar support [see port: without satellites, performance of many table 3-l]. Moreover, the Soviet Union has military missions would become impossible, and performance of others would require large ‘Force multiplication, in those cases where it is meaningful and can be assessed, can be assessed in absoluti terms and com- increases in the unit strengths of various U.S. pared between nations. force elements. Other force elements probably ‘Just as international comparison of utility is unjustifiable derive negligible force multiplication from in principle, international comparison of dependence on space systems is also unjustifiable, if dependence is defined as the space support. In general, however, the util- loss in utility which it would suffer if its satellites were sud- ity of military satellites to both the United denly incapacitated. Nevertheless, it is apparent that the United States and the Soviet Union is probably in- States is more dependent on MI LSATS to perform important 3 military functions than is the Soviet Union, even though the creasing. It is also generally believed that be- value of these functions cannot be easily quantified. cause of the expense of other means of providing comparable support to these forces, the Table 3“1.—Asymmetries in U.S. and Soviet United States has not vigorously developed Space System Need and Use alternative means of support and has consequently become highly dependent on space Asymmetry United States Soviet Union 4 system support. MILSAT reliability . . . . . (+) High (–) Lower MILSAT endurance . . . . (+) Long (–) Shorter Whether the United States derives more Launch rate...... (–) Low (+) High military utility from space system support Stockpile of spare MI LSATS ...... (–) Low (+ Higher than does the Soviet Union probably cannot C 3 requirements ...... (–) Global and (+ Continental be answered in general terms,5 although force oceanic and littoral Terrestrial C3 3See, e.g., Stephen M. Meyer, “Soviet Military Programs and alternatives (relative the ‘New High Ground ’,” Sm”val, %pt./Oct. 1983, pp. 204-215. to requirements) . . . . . (–) Few (+ More ‘Ibid. Terrestrial alternatives ‘According to accepted (e.g., Von Neumann-Morgernstern) for information axioms of utility theory, utility cannot be assessed in absolute collection (relative to terms but only to within an affine transformation; hence inter- requirements) ...... (–) Few (+) More personal or international comparisons of utility are not justifi- Operational ASAT able in general. See, e.g., Thomas Schelling, The Strategy of capability ...... (–) No (+) Yes Conflict (New York: Oxford University Press, 1960), p. 288n, ASAT altitude reach . . . (–) Low (+) Higher and John Rawls, A Theory of Justice (Cambridge, MA: Har- ASAT responsiveness . . (+) High (–) Low vard University Press, 1971), p. 90. 35 greater capability to reconstitute satellites rity, such as monitoring compliance with arms which provide such support in case they are control agreements 10 and collecting data ‘or lost in action, hence even to the extent the So- scientific research which could improve future viet Union is dependent on space system sup- military capabilities. port, it is less dependent on individual satellites for some functions. Current and Projected MILSAT Capabilities Force Application Satellites have also been used to provide de- Important asymmetries exist between the structive capabilities. For example, since 1968 space systems of the United States and the the U.S.S.R. has tested a coorbital intercep- Soviet Union and between the ways in which tor—a satellite which could be used to inter- these systems would be employed [see table cept and destroy other satellites. The U.S. De- 3-l]. However, simple comparisons of U.S. and partment of Defense estimates that the Soviet Soviet space systems can be misleading. The Union attained an operational anti-satellite ca- Soviet Union has an operational ASAT weap- pability with this weapon in 1971.* Although on, the United States does not. Yet, the U.S. to date there has been little testing and appar- ASAT, if developed, will be more capable and ently no long-term basing or actual use of versatile than the Soviet ASAT. U.S. satellites weapons in orbit, there is increasing techno- are more sophisticated, more reliable, and ca- logical potential to do so and, in the United pable of performing more functions than their States, increasing overt interest in doing so. Soviet counterparts. Yet, the Soviet’s rapid In particular, there is strong interest in the launch capability and policy of maintaining United States in using space-based (i.e., sat- spares would allow them to reconstitute some ellite) weapons for defensive missions, espe- space assets during a conflict. *1 cially ballistic missile defense and air defense. These factors are further modified by the Satellites could also provide destructive ca- different roles that satellites or ASAT weap- pabilities in support of other missions. Pub- ons would play in different theaters of war at lic Soviet statements have indicated a decreas- different levels of conflict. Soviet forces are de ing interest—indeed, growing opposition—to ployed largely on the Eurasion land mass, and space-based weapons, although such state- would, in many scenarios, be able to rely on ments have been interpreted by some in the terrestrial communication and information West as disingenuous and propagandistic, in- links. In many’of the same scenarios, satellite tended for political gain and strategic de- communications would be critical to globally ception. g deployed U.S. forces which might lack the same terrestrial communication links. Even in Nonmilitary Functions Contributing to peacetime, the United States relies heavily on National Security surveillance satellites to monitor Soviet compliance with arms control agreements by mon- Satellites are also used for nonmilitary ap- itoring Soviet activities which could not be plications which contribute to national secu- monitored by other lawful means, although Y.J.S. Department of Defense, Soviet Military Power, 4th cd., similar activities in the United States would Apr. 1985, p. 55. According to analysts of the Congressional be readily observable by Soviet personnel k+ Research Service, the U.S.S.R. has also tested a fractional-orbit bombardment system (FOBS), and possibly also a multipk+orbit gaily in the country. bombgrdrnent system (MOBS), which could employ sateMtes to bombard terrestrial targets with nuclear warheads W.S. Con- gress, Library of Congress, Congressional Research Service, Science Policy Research Division, Soviet &ace Programs, 1971- 1975, Committee Print prepared for the U.S. Senate, C%mrnit- tee on Aeronautical and Space Sciences, Aug. 30, 1976]. ‘OLes Aspiu “The Verification of the SALT II Agreement, ” ‘U.S. Department of Defense, Defense Intelligence Agency, Scientific American, vol. 240, No. 2, February 1979, pp. 38-45. Soviet Mih”tary Space Doctrine, report DDB-1400-16-84, Aug. “president Ronald Reagan, Report to the Congress: U.S. PoJ 1, 1984 [UNCLASSIFIED]. icy on ASA T Arms Control, Mar. 31, 1984 ~NCLASSIFIED]. 36

Soviet MILSAT Capabilities over a limited range. The observation “swath’ The Soviet Union currently uses satellites of each satellite will eventually cover the en- to perform missile launch detection, commu- tire earth and ocean surface between latitudes nications relaying, radionavigation, meteoro- of about 650 north and south. If only one or logical surveillance, photographic and radar two RORSATS or EORSATS were operational reconnaissance, collection of electronic intel- at one time—as has been customary in peace- ligence (ELINT: e.g., radar emissions), and time–then a ship in this latitude band would 12 be exposed to observation only intermit- other functions. These functions support a g variety of military applications. Of particular tently.l However, larger numbers of ROR- concern to the Administration and in Con- SATS or EORSATS could be operational dur- gressl$ are: ing wartime. . . . present and projected Soviet space sys- Even if only intermittent, surveillance by tems which, while not weapons themselves, RORSATS or EORSATS could assist Soviet are designed to support directly the U. S. S.R. ’S forces in targeting Allied shipping to an ex- terrestrial forces in the event of a conflict. tent dependent on details of satellite capabil- These include ocean reconnaissance satellites ities, such as resolution. For example, Soviet which use radar and electronic intelligence in oceanographic radar satellites of the Kosmos- efforts to provide targeting data to Soviet 1500 class can obtain radar imagery with a 14 weapon platforms which can quickly attack resolution of only 1.5 to 2 kilometers [see fig- U.S. and allied surface fleets. In view of the ure 3-2], which is inadequate to distinguish an fundamental importance of U.S. and Allied aircraft carrier from a tanker, for example.17 access to the seas in wartime, including for Various countermeasures could be used by Allied reinforcement by sea, the protection of U.S. and allied navies against such target- ships to evade observation by these satellites ing is critical.ls or to reduce the value of their observations to the enemy; la some of these are discussed be- Soviet ELINT ocean reconnaissance satel- low, in the section entitled “The Role and lites (EORSATS) attempt to detect, localize, Value of Anti-Satellite Capabilities. ” and classify ships by detecting the radio signals emitted by their communications and ra- U.S. MILSAT Capabilities dar systems, while Soviet radar ocean recon- The United States uses MILSATS to per- naissance satellites (RORSATS) attempt to form most of the functions performed by So- detect, localize, and classify ships by detect- viet satellites, as well as some other functions. ing radar “echoes” reflected by the ships. RORSATS and EORSATS are typically de- .— W!ompare the discussion of radar search satellites in I14X lkfis- ployed at altitudes of about 250 and 425 kilom- sile Basing, OTA report OTA-ISC-140, September 1981. eters, respectively, in nearly circular orbits in- ITIn 1983 the ~viet Union launched a Cid Ocean-surveillance clined about 650 with respect to the equatorial satellite (Kosmos 1500) equipped with a side-looking radar and in the same year placed two satellites (Venera 15 and Venera plane [see figure 3-1 and table 3-2] From these 16) equipped with similar radar systems into orbits around VE+ altitudes, these satellites can observe shipping nus. The U.S.S.R, has exhibited radar imagery obtained by these satellites. Although the resolution of this radar imagery IZ1bid., pp. T ~d 12; and U.S. Navy, Office of the Chief of is poor compared to the 25-meter resolution imagery obtained Naval Operations, Understanding Sow”et Naval Developments, by NASA’s Seasat-A radar satellite in 1978 [see Figure 76B 4th cd., NAVSO P-3560 (Rev. 1/81), Jan. 1981 IUNCLASSI- of U.S. Congress, Office of Technology Assessment, hZX Mis- FIED], p. 46. sile Basing, OTA-ISG140, Sept. 1981], the 40-meter resolution ‘sHearings before the Subcommittee on Strategic and Thea- imagery obtained by NASA’s experimental Shuttle Imaging ter Nuclear Forces of the Cou’ttee on Armed Serw”ces Um”ted Radar (SIR-A) device in 1982 [see figure 3-3], or the 25-meter States Senate, Testimony on Space Defense Matters in Review resolution imagery obtained by NASA’s experimental Shuttle of the FY1985 Defense Authorization Bill, S. Hrg 98-724, Pt. Imaging Radar (SIR-A) device in 1984, Soviet satellite radar 7, pp. 3568-3569. technology can be expected to improve, and synthetic aperture “Specifically, anti-ship cruise missiles launched against U.S. radar could be used on future satellites. surface ships: see U.S. Department of Defense, Soviet Mfi”tmy “Reagan, op. cit., p. 13. See also testimony of VADM Gor- Power, 3d cd., 1984; p. 41. don R. Nagler, USN, before the HAC Subcommittee on Defense, “Reagan, op. cit. Mar. 23, 1983. 37 ———— —

Figure 3.1 .—Ground Track of Soviet Radar Ocean Reconnaissance Satellite

600 inclination 160-170 nmi altitude 1.5-1.6 hr period

SOURCE Office of Technology Assessment

Table 3“2.—Orbits of Some Soviet Military Satellites U.S. satellites are designed to have longer operational lifetimes in orbit than Soviet sat- Per[gee-Apogee ellites, hence fewer satellite launches per year (km) (km) Inclination Apparent mission ● 35,785-35,785 0 communications are required to perform similar functions. The 19,000-19,200 65 navigation complexity of a U.S. satellite may differ from 965-1,020 47 communications that of a Soviet satellite performing the same 940-960 83 meteorological 855-895 81 meteorologyical function, and the value of this function to the 790-810 74 communications United States may differ from its value to the 620-660 81 electronic lntelligence U.S.S.R. (ELI NT) 425-445 65 ELINT ocean reconnaissance Attack Warning.-The United States uses in- (RORSAT) 760-40,000 63 launch detection frared sensors aboard satellites in geostation- 400-40,000 63 communicatlons ary orbit to detect and promptly report ICBM 356-415 73 photo- reconnaissancea and SLBM launches; these reports would pro- 250-265 65 radar ocean reconnaissance 19 (RORSAT) vide early warning of a missile attack. b 172-351 ———.67 photo-reconnaissance.— aManeUVerab}e ]nltlaj parameters for Kosmos 1499 91ven bManeuverab~e Inltlal parameters for Kosmos 1454 glve~ “U.S. Dep~rtment of Defense, Report of the Secretar~ of De- SOURCES NASA Sa/e///fe S~fuaf[on Report VOI 24 No 5 Dec 31 1984 and fense Caspar 1$”. W’ehberger to the Congress on the FY 1985 “ Nicholas L Johnson The Sov/et Year In Space 7983 (Colorado 13udget, F}r 1986 Authorization Request, and FY 1985-89 De- S~r!ngs CO Teledyne Brown Eng(neerlng 1984) fense Programs, Feb. 1, 1984 IUNCI,ASSIFIEDL p. 196. 38

Figure 3-2.- Radar Imagery From Kosmos 1500

. .,

Left, imagery of Atlantic Ocean waves obtained by the Soviet Kosmos 1500 Oceanographic Research Satellite in 1983:

SOURCE: Photographs courtesy of Aviation Week and Space Technology (reprinted by permission)

Navigation and Detection of Nuclear Detona- Treaty and other treaties in peacetime. In war- tions.—U.S. NAVSTAR satellites carry radi- time they could be used to confirm a nuclear onavigation beacons for use by Global Posi- attack on the United States or its allies in or- tioning System (GPS) receivers on aircraft, der to support a decision by the National Com- ships, and land vehicles. They also carry In- mand Authorities to retaliate, and to assess tegrated Operational Nuclear Detonation De- the success of a retaliatory strike.20 tection System (IONDS) sensors designed to detect nuclear detonations in order to monitor compliance with the Limited Test Ban ‘“Ibid. 39

Command and Control Communications.—The Possible Advanced-Technology United States also uses several different mil- MILSAT Capabilities itary and commercial communications satellites to provide command and control commu- Recent and prospective technological ad- nications among its globally distributed forces. vances could be exploited by both the United An advanced satellite communications system States and the U.S.S.R.–at different rates–to called MILSTAR has been designed to replace develop MILSATS which could perform those these and is intended to provide survivable functions now performed by MILSATS more and enduring command and control commu- effectively or economically. Such improve- nications to all four services at all levels of con- ments are possible in the performance of each flict, including general nuclear war.” of the functions mentioned. Of particular interest and concern are possible marked im- Meteorological Surveillance.–Defense Mete- provements in ocean surveillance, logistic orological Satellite Program (DMSP) meteoro- support of space systems, and anti-satellite ca- logical surveillance satellites provide timely pability which appear technologically feasible. information about weather conditions worldwide. This information is of considerable value For example, radar ocean surveillance sat- in planning military operations, especially ellites using synthetic aperture radar tech- flight operations. niques could provide radar imagery of sufficient resolution to permit classification of Compliance Monitoring.–Photoreconnais- ships. An example of the potential quality of sance satellites are used to monitor compliance radar imagery is provided by the radar im- with arms control treaties and agreements; agery obtained by the Shuttle Imaging Radar this function could not be performed as well system SIR-A in 1981 [see figure 3-3]. The syn- by any alternative means which is politically thetic aperture radar carried by SIR-A distin- acceptable in peacetime, and this function guished features as small as 40 meters across. would be unnecessary during war with another Earlier, in 1978, NASA’s Seasat-A demon- party to such treaties, which would be sus- strated a resolution of 25 meters; more re- pended during such a war. However, in war- cently, in 1984, SIR-B demonstrated a com- time the United States would attempt to col- z parable resolution. Even finer resolution is lect intelligence using satellites’ and other possible, and several satellites could be de- means, such as aircraft overflight, which are ployed at once to provide frequent opportu- acceptable during wartime. nities to observe each point on the ocean surface. [Deploying such satellites at higher altitudes for greater coverage would greatly “The Honorable Caspar W. Weinberger, Secretary of Defense, Annual Report to the Congress on the FY 1984 Budget, FY increase the power required and hence also sat- 1985 Authorization Request, and FY 1984-88 Defense Pro- ellite cost.] Both the United States and the grams, Feb. 1, 1983 [UNCLASSIFIED]. U.S.S.R. could deploy radar ocean surveillance “The Honorable Richard Perle, Assistant Secretary of De- fense for International Security PoIicy, has stated: satellites using high-resolution synthetic aper- W’e believe that this Soviet anti-satellite capability is effec- ture radar technology in the future. Soviet de- tive against critical U.S. satellites in relatively low orbit, that ployment of radar ocean surveillance satellites in wartime we would have to face the possibility, indeed the likelihood, that critical assets of the United States would be de- with improved performance would threaten stroyed by .Soviet antisatellite :~stems. If, in wartime, the Soviet Union were to attack crltlcal satellites upon which our U.S. and allied shipping to a greater extent knowledge of the unfolding conventional war depended, . . . we than does the existing RORSAT and would would ha~’e little choice but . to deter continuing attacks on provide the United States with a greater in- our eyes and ears, without which we could not hope to prosecute successfully a conventional war, centive to maintain, or, if necessary, develop [Hearings before the Subcomrm”ttee on Strategic and Thea- an A SAT capability to destroy such satellites ter NucJear Forces of the Com”ttee on Armed Services Um”ted States Senate, Testimon-v on Space Defense Matters in Review or otherwise interfere with their performance. of the FYI 985 Defense A uthorizati’on Bill, S.Hrg. 98-724, Pt. Future EORSAT performance could also be 7., Mar. 15, 1984, p, 3452. ] improved. With regard to the threat posed by 40 .—

ASAT capabilities are discussed in chapter 4 of this report. Recent and prospective technological advances could also be exploited to enable future MILSATS to perform functions not now performed by MILSATS. For example, the United States could develop and deploy space surveillance satellites to detect and track foreign satellites. This capability could be used to detect impending attacks on U.S. or allied satellites in time to permit countermeasures to be used; it could confirm success of such attacks in order to support a decision to retaliate (not necessarily in kind); it could monitor compliance with possible future ASAT arms control or “Rules of the Road in Space” agreements; and it could provide targeting information for U.S. anti-satellite weapons. Space surveillance satellites could provide continuous space object detection and tracking capabilities which cannot be duplicated by ground-based radars (which have limited search range) and photographic or electro-optical sensors (which cannot be used in daytime or through overcast). The United States and the U.S.S.R. could also develop satellite (i.e., space-based) weapons capable of attacking a variety of targets other than satellites—e.g., ballistic missiles, aircraft, ships, and fixed or mobile targets on land.24 Assessment of the military capabilities which such weapons might eventually be able to provide requires an understanding of the feasibility of making them survivable at affordable costs and is beyond the scope of this report, which is limited to survivability issues. such Soviet MILSATS to U.S. and allied ship- The feasibility and value of space-based bal- ping, the Administration has expressed concern listic missile defense system components– that “as Soviet military space technology im- including weapons—is discussed in a compan- proves, the capabilities of Soviet satellites that ion OTA report, Ballistic Missile Defense can be used for targeting are likely to be en- Technologies. hanced and represent a greater threat to U.S. and allied security. ”23 The Value of Military Satellites The logistic support and anti-satellite capa- Estimation of the force multiplication ef- bilities of space systems could also be en- fects which satellites might provide under spe- hanced greatly in the future. Potential future cific circumstances might be done objectively, by means of combat modeling and simulation, ‘ ‘Reagan, op. cit., p. ‘i. See also testimony of VAI)M Gordon R. Nagler, USN, hefore the IIAC Subcommittee on Defense, Nlar. 23, 1983. “LTC David I.upton, USAF (Ret.), op. cit., pp. 36-47. and analysis of historical combat data. The tion which they perform has been called “vi- costs of the additional ‘‘equivalent forces’ tal.‘ ’28 which the satellite services would, in effect, re- Other satellites are seldom judged to be of place might be used as an upper bound on the importance comparable to those aforemen- value of the satellites under those circum- tioned, although some are of considerable stances. However, the expected utility, or value. For example, after DMSP cloud im- worth, of such force multiplication cannot de- agery and DMSP-derived forecasts were made termined by such an analysis without assum- available to aircraft carriers operating in ing probabilities that the forces supported will be involved in various conflict situations, esti- Southeast Asia, sorties of carrier-based air- mating the force multiplication expected in craft scheduled for strike and reconnaissance missions which required clear weather in the each such situation and the additional costs target area were canceled when meteorologi- averted by such force multiplication, and cal data from DMSP satellites showed over- averaging these averted costs over all such cast in the target area, and the aircraft which situations. This would be a demanding, and had been assigned to the canceled sorties were probably infeasible, analytical task, because reassigned to other missions. This use of assessment of such values and probabilities DMSP data decreased the number of aircraft is necessarily subjective and hence subject to required to perform a number of assigned mis- dispute. However, some judgments of value sions in a given time, or, equivalently, in- are conventionally accepted and can be ration- creased the number of aircraft available to fly alized to a considerable extent. such missions. For example, the missile attack warning As another example, the navigational ac- function performed by U.S. MII.SATs has curacy of missiles and aircraft which rely on been described as being of “vital’ importance very accurate, unaided inertial navigation sys- to national security. ” The navigation and nu- tems depends on geopotential anomaly data clear detonation detection functions performed collected by geophysical research satellites. by the GPS and IONDS mission packages aboard NAVSTAR satellites have been de- Some of the functions performed by satel- scribed as “critical,” as has the communica- lites, and the satellites which perform them, tions function to be performed by MILSTAR are most valuable in peacetime, while others and currently performed by a variety of sat- would be more important in crisis, conven- ellites [see box entitled “The Dependence of tional war, or nuclear war. However, determi- U.S. Command and Control Performance on nation of the nature of the dependence of Satellite Communications Systems’’ ].” Sur- satellite value on the level of conflict is com- veillance satellites have been described as plicated by the fact that in many cases the “criticaI assets, “27 and the surveillance func- critical U. S, sat ellites in relat, ik’el~’ low orhit, that in wartime we would ha~’e to face the possibility’, incfwxf the likelihood, that critical assets of the on it ed States would he dest rolred b)’ So- \’iet anti- sat[lllite sj’stems. ---Statement of l’he I lonor:ihl[ Richard f]erle, Assistant Secretary” of I)efensc ( 1 nternati{)nal Securit~’ I)oliq), Hearings hefore the Suhcommit tfw on Str;I- tegic and Theater Aiuclear Forces of the [’on]mit tet’ on .Armed .Ser\riceL9 ( lnited States Senate. Testin]on.)r on .Space llefen.se hfatters in fle~’ieu of the F>”] 985 L)efense .4u[horizatjon Bill, Klar, 15, 1984, S, Ilrg. 98-724, Pt. i’, p. 3452. 2“The l+onorahle I lans hl ark, then SecretarJr of the .4ir Force, in test imon}” in 1980 hearings before the U.S. Congress, 1+ ouse ( )f 1{ eprc,w~n t at i ~c~, (’ommittet’ on Science and “1’echnolo~~, Stat f~d that ‘‘ two missions [strategic missile warning arrci sur- t’t’illan((~j al)oi(~ al] {)ther-s stand out as }~~in~ of \’i tal inlpor- t :incf~ t () national sf’curit J. [ ( ‘nitd St at(Is (’i\’ iJian Spa(v I’ol- ic’,~, 1 IOUS(J I )(KU rnf’nt 15;1, !Mt h (Tong., Yd s[~ss,, ,Jul I’ 2324, I :W(}: pp. 9:)-WI\. 42

The Dependence of U.S. Command and Control Performance on Satellite Communications Systems It has been estimated that about 70 percent of all U.S. military electronic communications are routed through communications satellites.1 In peacetime, much of such traffic consists of administrative messages which would be unessential to the conduct of war. Therefore, the dependence of U.S. military capabilities on satellite communication systems, although undoubtedly substantial, is not necessarily represented accurately by the fraction of message traffic routed through satellites during peacetime. The dependence of U.S. military capabilities in several theaters on satellite communication systems is reflected qualitatively in the following views of military commanders and staff analysts. Command and Control in the Southwest Asian Theater.–The dependence of command and control within the Southwest Asian theater and between that theater and the continental United States on satellite communications systems has been noted by Lieutenant General Robert C. Kingston, USA (Commander, Rapid Deployment Joint Task Force): . . . the challenge is to establish and maintain strategic communications upward, necessary linkages laterally, and tactical communications downward. Strategic connectivity in the [Southwest Asian] region is limited today. The backbone of the Defense Communications System cannot be accessed directly except by satellite or HF over long distances. The FLTSAT and DSCS II systems support this need for all the services. DSCS 111, the follow-on satellite, will soon be launched with a new booster. The HF programs, however, especially in the anti-jamming arena, need better interoperability. At present, limited HF links must transmit beyond optimum distances to reach DCA entry points and are subject to frequent atmospheric interruptions.2 Command and Control in the Pacific Theater.–Similar concern has been expressed by Lieutenant General Joseph T. Palastra, Jr., USA (Deputy Commander-in-Chief, Pacific) about the dependence of command and control within the Pacific theater and between that theater and the continental United States on satellite communications systems: A critical problem is the Pacific area’s heavy reliance on satellite and undersea cable systems. The So- viet Union’s demonstrated ability to destroy satellites has made it urgent to implement countermeasures and modernize backup high frequency systems so we can deploy at least minimum essential communications. s Command and Control in the European Theater.– Command and control between the European theater and the continental United States depends on similar means which are similarly vulnerable. Command and control within the European theater depends less on satellite communications, for reasons noted by Major General Robert A. Rosenberg, USAF (then Assistant Chief of Staff, Studies and Analyses, Headquarters, U.S. Air Force): It is interesting to watch a simulated war-game exercise in the central region of Europe when the communications circuits are removed to simulate loss or destruction. The German Post Office telephone system is used to contact another command center when the military primary lines are down.4

‘Colonel Robert B. Giffen, US Space System Survivabih”ty: Stretegic Alternatives for the 1990s, National Security Affairs Monograph Series 82s4 (Washington, D.C.: National Defense University Press, Fort Leslie J. McNsir, 1982), pp. 22-23. *Lieutenant General Robert C. Kingston, USA, “C$I and the Rapid Deployment Force, ” Worldwide Deployment of Tactical Forces and the OZ Connection, Pr oceedings of the National Security Issues 1982 Symposium, Oct. 4-5, 1982, MITRE Corp. document M82-64, 1982. %ieutenant General Joseph T. Palastra, Jr., USA, “Pacific Command Perspectives, ” Worldwide Deployment of Tactical Forces and the 01 Connection, Proceedings of the National Security Issues 1982 Symposium, Oct. 4-5, 1982, MITRE Corp. document M82-64, 1982. ‘Major General Robert A. Rosenberg, USAF, “Satisfying C’I Requirements for Deployed Air Forces, ” Worldwide Deployment of Tactical Forces and the (Y1 Connection, Proceedings of the National Security Issues 1982 Symposium, Oct. 4-5, 1982, MITRE Corp. document M82- 64, 1982. 43 value of a function performed by a satellite satellites themselves (the “space segment”). may be realized at a later time and at a dif- Attacks against either segment can disrupt ferent–probably higher-level of conflict than the functioning of a military space system and that at which the function was performed. negate or reverse the force enhancement it pro vides. Hence both MILSATS and their asso- For example, missile attack warning data ciated ground equipment must be effectively would be most valuable during a nonnuclear protected against attack if the value of their war, when anticipation of such an attack wartime functions is to be realized. Technical would be most intense and when it would be measures—i.e., active and passive counter- most important to be reassured that the na- measures—can provide some protection by re- tion is not under attack when such is indeed ducing the MILSAT vulnerability, and legal the case. Once the United States has con- measures—i.e., arms control treaties treaty or firmed that it has been so attacked, or is un- customary law banning threatening activities der attack, or decides to retaliate for a non- in space—can provide some protection by con- nuclear attack by Warsaw Pact forces against straining ASAT capabilities which could be NATO allies, further warning information used against MILSATS. Arms control meas- would be of value only if additional salvos were ures could be used in combination with pas- expected, as in “nuclear war-fighting” scenarios. sive countermeasures to constrain potential As another example, the value of geopoten- ASAT threats and reduce vulnerability to tial anomaly data collected by satellite might those which would remain. However, some be greatest during nuclear war, although to arms control measures would be incompatible be of value then such data must have been col- with some active countermeasures, such as lected and analyzed-a lengthy process– shoot-back with ASAT weapons. during peacetime. U.S. responses to current and future ASAT The problem of assessing the values of MIL- threats need not be limited to legally con- SAT capabilities and ASAT capabilities will straining such threats and protecting and be discussed in greater detail in appendix D defending satellites from those which remain. to this report. Other possible responses include deterrence of ASAT attack by maintaining a capability to The Vulnerability and Protection of retaliate (not necessarily in kind), using non- Military Space Systems destructive electronic countermeasures and electro-optica.1 countermeasures against the The value of MILSAT functions performed space and ground segments of A SAT systems, during wartime can be realized only if MIL- attacking the ground segment of ASAT sys- SATS survive long enough to perform them. tems, augmenting other forces to compensate Most current MILSATS are vulnerable to de- for MILSAT vulnerability, and reducing deliberate nuclear or nonnuclear attack, and pendence on MILSATS. some are vulnerable to nondestructive elec- [Technical countermeasures are discussed in tronic countermeasures and electro-optical greater detail in chapter 4 of this report, and countermeasures. However, only a few U.S. arms control and other legal measures are disc- MILSATS are potentially vulnerable to cur- ussed in chapters 5 and 6. In practice, pas- rent Soviet nonnuclear A SAT weapons, and sive countermeasures, and probably active these could be made less so. countermeasures as well, would be used in con- Satellites operate as components of space junction with arms control; such combinations systems, which include terrestrial components of arms control and technical countermeasures such as satellite control facilities and user ter- are discussed in greater detail in chapter 7 of minals (the “ground segment”) as well as the this report.] 44

THE ROLE AND VALUE OF ANTI-SATELLITE CAPABILITIES

To the extent that enemy MILSATS could enemy and, more importantly, to mitigate or increase the effectiveness of enemy forces, ca- compensate for the harm such satellites could pabilities to damage such MILSATS or to de- cause the United States. Intelligence-gather- grade their functioning would be valuable in ing satellites may be particularly susceptible wartime. In addition to such destructive and to such measures. For example, terrestrial nondestructive ASAT capabilities, other op- force elements might employ maneuver to tions are available to reduce the utility of MIL- avoid observation by enemy imaging satel- SATS to an enemy or to compensate for their lites, and they could use camouflage and con- disutility to the United States. cealment to prevent recognition if observed. Decoys which would also be “recognized” er- Electronic and electro-optical countermeas- roneously could be used to thwart image inter- ures can be used to provide nondestructive pretation by causing confusion as to the num- ASAT capabilities which could be used at any bers and locations of the assets simulated by level of conflict. They would be particularly the decoys. Ships, aircraft, and other assets valuable during crises short of declared war, might be designed to reflect radar signals only in which satellite destruction would be escala- weakly in order to evade detection by radar tor and hence in many cases undesirable. satellites, and radio silence might be practiced, “Active” electronic countermeasures such as or covert signaling techniques used, in order “jamming” (i.e., overloading enemy receivers to prevent detection of radio emissions by sat- with strong signals) and “spoofing” (i.e., send- ellites. Of course, these passive measures ing deceptive signals) could be used to inter- would impose either operational constraints fere with satellite functioning, as could such or financial costs or both. active electro-optical countermeasures as temporary blinding (or “dazzling”: the optical Still other options are available to compen- counterpart to jamming ) and spoofing. Such sate for, rather than mitigate, the harm which nondestructive ASAT measures are discussed foreign MILSATS could cause to U.S. and al- in chapter 4 of this report. lied security. For example, to the extent that foreign MILSATS provide a force multiplier At higher levels of conflict, ASAT weapons effect to foreign force elements which engage could be used to destroy enemy satellites. The in direct combat, U.S. or allied force elements inherent ASAT capabilities of nuclear weap- which might oppose these foreign force ele- ons such as ICBMS and SLBMS could be used ments might be augmented in order to main- for negation of low-altitude MILSATS at nu- tain relative combat strength. That is, force clear levels of conflict, while at nonnuclear augmentation could offset the force multipli- levels of conflict the inherent ASAT capabil- cation provided to enemy forces by space sup- ities of the experimental nonnuclear ABM port. Force augmentation would be costly, but technologies demonstrated in Homing Over- not necessarily more costly than an ASAT ca- lay Experiment (HOE) tests could be used for pability of comparable security benefit. low-altitude MILSAT negation, as could the U.S. Air Force’s Miniature Vehicle ASAT These possible responses to threatening weapon, when operational. Negation of satel- MILSAT capabilities are summarized in ta- lites at higher altitudes or more rapid nega- ble 3-3. These response options would be more tion of low-altitude satellites would require effective used in combination rather than in- more capable ASAT weapons such as are dis- dividually. cussed in chapter 4 of this report. Assessment of the value of ASAT capabil- Alternatively, or supplementally, various ity is subject to the same methodological passive measures could be used in peacetime, difficulties which confound assessment of the value of MILSAT capability .29 These prob- crisis, and war not to interfere with the func- —. ———— tioning of enemy MILSATS but rather to de- *’The value of a U.S. ASAT capability to the United States crease the value of their functions to the in a conflict could be assumed to be equal in magnitude to the 45

Table 3-3.—Possible Responses to lems, noted above, are discussed in greater de- Enemy MILSAT Capabilities tail in appendix D to this report. Although ● Force augmentation quantification of the value of ASAT capabil- —offsets force multiplication by MILSATS ity is necessarily subjective or complicated, or ● Passive measures against satellite reconnaissance and both, it is clear that operational ASAT capa- targeting — Evasion bilities would have some value to the extent —Concealment that they would be inexpensive, stabilizing, —Camouflage and compatible with other (e.g., diplomatic) op- —Decoys —Radio/radar silence tions for enhancing security. —Covert communications techniques ● [negative] total value to the Um”ted States of those enemy MIL- Nondestructive anti-satellite measures SATS which it would be expected to destroy. No analytically —Electronic countermeasures sophisticated studies known to OTA have attempted to syste- Jamming matically assess and compare the utility of U.S. MILSATS to ● Spoofing the United States with the disutility of Soviet MILSATS to —Electro-optical countermeasures the United States but compare Stephen M. Meyer, op. cit., pp. ● Jamming 204-215]. It is these utilities which should be compared to de- ● Spoofing ● termine whether the United States would fare better in a re- Destructive anti-satellite measures gime in which U.S. and Soviet MILSATS were mutually vul- —Use inherent ASAT capabilities of ICBMS, SLBMS, nerable to the other’s ASAT weapons or in a regime in which and ABMs U.S. and Soviet MILSATS were protected from A SAT threats —Develop deliberate ASAT weapons by active or passive countermeasures or arms control.

MILITARY SPACE POLICY

Military Space Policy Issues ASAT Policy Issues The fundamental task of military space pol- Particularly apparent is the incompatibility icy formulation is deciding how much pro- between ASAT capabilities and ASAT arms posed military space programs are worth, both control agreements; these would have differ- in terms of the resources for which they would ent kinds of benefits and risks, and a decision compete with other proposed national pro- to pursue one or the other must be based on grams, and in terms of opportunity costs a political judgement of their respective ex- which might be incurred by failing to take pected net benefits. A national ASATpolicy other actions (e.g., arms control) with which reflects such a judgement and should attempt such programs are incompatible for nonbudge to establish goals for national efforts to en- tary (e.g., legal) reasons. Because the costs, hance security by the chosen approach. In par- risks, and benefits differ in character, a polit- ticular, a national ASAT policy should: ical determination of levels at which military 30 1. describe military posture objectives; it space efforts should be pursued is required. should attempt to answer the question: Prerequisite for this is the task of deciding “What ASAT capabilities do we need, the relative values of proposed military space and why?” systems, anti-satellite systems, and arms con- 2. indicate the extent to which pursuit of trol agreements; judgment of these values also security by the chosen approach would requires political choice.31 probably benefit from increased spending in various areas of research and technol- 30 Representative of Such determinations are the annual lwdgets prepared by the executive branch and funds author- ogy development, so that national re- ized and appropriated by Congress. search and development policy might be “Representative of such determinations are President formulated cognizant of these potential Carter’s Presidential Directive 37 (PD-37) issued in June 1978, President Reagan’s July 4, 1982, statement on National Space benefits. Policy, and President Reagan’s Report to the Congress: U.S. 3. establish ASA T arms contro]policy; i.e., Policy on ASAT Arms Control, Mar. 31, 1984, it should indicate types of arms control 46

provisions or agreed confidence-building ment would also restrict BMD capabilities, measures which are judged to be in the just as the ABM Treaty-which limits, by in- national interest, in order to coordinate tent, weapons capable of attacking ballistic formulation of negotiating postures, in missiles-also limits ASAT weapons with in- particular, and foreign policy in general;32 herent BMD capability. Of all the opportunity and costs which might be imposed on the United 4. specify U.S. ASAT employment policy; States by an agreement to limit ASAT capa- i.e., it should specify conditions under bilities, restrictions on the development and which U.S. use of ASAT capabilities— deployment of BMD capabilities beyond those especially in conflicts short of declared already imposed by the ABM Treaty are con- war-would be deemed justifiable and in sidered most costly by those who believe that the national interest. In addition, if we de exploitation of advanced technology may sire to deter Soviet ASAT attacks, we make possible BMD weapons of great effec- must arrive at and announce a public pol- tiveness. icy which we believe will make this deter- A more fundamental incompatibility be- rence as effective as possible. Whether tween ASAT and BMD capabilities is physi- this policy should be explicit or instead cal rather than legal: the most capable BMD one of calculated ambiguity is a matter systems now envisioned would use space- of political judgment. based sensors, and perhaps also space-based weapons, which would be subject to attack by Ballistic Missile Defense as deliberate ASAT weapons or by BMD or other an ASAT Policy Issue weapons with inherent ASAT capabilities. Such BMD systems would be effective only The incompatibility between ballistic mis- if their sensors and weapons could be pro- sile defense capabilities and ASAT arms con- tected from such ASAT threats at reasonable trol agreements is apparent. Ballistic missile cost by passive countermeasures, active coun- defense weapons which would be capable of at- termeasures, arms control measures, or a com- tacking ballistic missile components in space bination of these. If so, perhaps such measures generally would have some inherent capabil- could be used to protect other satellites, or else ity to attack satellites at altitudes or ranges the functions now performed by other satel- comparable to those at which ballistic missile lites could be performed by secondary mission components would be engaged, depending on payloads “piggybacking” on BMD satellites. The inherent ASAT ca- satellite “hardness.” If not, such BMD capabilities would be of lit- pabilities of some possible advanced-tech- tle value, if any, and the opportunity costs nology BMD weapons would be considerable, which would be incurred by restricting them and any arms control agreement which would would be small. attempt to limit the threat of such weapons to satellites must ban or limit such weapons. [Chapter 5 of this report contains a discus- Hence a restrictive ASAT arms control agree- sion of past arms control efforts which had the intent or effect of constraining ASAT capabilities. Other ASAT arms control options are described and evaluated on a provision-by- z ‘ Representative of such a policy is President Reagan’s Re- provision basis in chapter 6 and as packages port to the Congress: U.S. Poficy on ASATArms Control, delivered Mar. 31, 1984. of provisions in chapter 7.] Chapter 4 ASAT Capabilities and Countermeasures Contents

Page Organization of This Chapter ...... 49 Current and Projected ASAT Capabilities...... 49 Generic ASAT System Components , ...... 49 Soviet ASAT Capabilities ...... 50 U.S. ASAT Capabilities ...... 55 Possible Advanced-Technology ASAT Weapon Systems...... 62 Isotropic Nuclear Weapons ...... 62 Kinetic-Energy Weapons ...... 64 Directed-Energy Weapons ...... 66 Possible U.S. Responses to Soviet ASAT Capabilities ...... 75 Reduction of Dependence on Military Satellites ...... 75 Force Augmentation ...... 76 Passive Countermeasures ...... 76 Active Measures ...... 84 Diplomatic Measures...... 86 Summary of Findings Regarding ASAT Capabilities and Countermeasures ...... 86

Tables Table No. Page 4-l. Estimated Costs of the U.S. Air Force Space Defense and Operations (ASAT) Program ...... 62 4-2. Types of ASAT Weapons ...... 63 4-3. A Comparison of Laser Weapons. ., ...... 72 4-4. Passive Countermeasures Against ASAT Attacks ...... 77 4-5. Active Measures Against ASAT Attack ...... 84

Figures Figure No. Page 4-1. Generic Components of an ASAT System ...... 50 4-2. Illustrative Components of the U.S. Space Defense System ...... 51 4-3.The Soviet Coorbital Satellite Interceptor ...... 53 4-4. Soviet Anti-Satellite Capabilities...... 54 4-5. Space Detection and Tracking System ., ..., , ...... 56 4-6. Deep Space Surveillance Systems ...... 57 4-7. ASAT Mission Operations Concept...... 58 4-8. Mission Control Events ...... , ...... 59 4-9. The USAF Miniature Vehicle...... 60 4-10. ASAT Mission Profile...... 61 4-11. Artist’s Concept of a Neutral Particle Beam Weapon ...... 72 4-12. Artist’s Conception of the Space Shuttle Deploying a Neutral Particle Beam Weapon ...... 74 4-13. Cost Comparison: Satellite and RPV Relays for Single-Channel UHF Tactical Theater Communications ...... 76 4-14. Low-Cost Packet-Switching Communications Satellite ...... 83 Chapter 4 ASAT Capabilities and Countermeasures

ORGANIZATION OF THIS CHAPTER

A variety of technological options are avail- Some possible U.S. responses to Soviet devel- able for space surveillance systems, stand-off opment of such capabilities are described in weapons, and weapon and sensor platforms for the third section of this chapter. The principal anti-satellite uses. Current and projected U.S. conclusions about ASAT capabilities and and Soviet ASAT capabilities, including space countermeasures are summarized in the final surveillance capabilities, are described in the section of this chapter. The actual military first section of this chapter. More advanced utility of these capabilities will be discussed ASAT capabilities which could be deployed by in appendix D to this report, which is clas- the United States or the U. S. S. R-. are de- sified; scribed in the second section of this chapter.

CURRENT AND PROJECTED ASAT CAPABILITIES

Generic ASAT System Components C* elements would generate detailed instructions for an attack, and these would be com- A space defense system could include both municated by C3 links to an ASAT weapon passive countermeasures for protecting satel- system. lites and an ASAT system for interfering with enemy satellites in time of war. An ASAT sys- An A SAT system would have either nondes- tem, whether deliberate or expedient, must be tructive ASAT devices such as jammers or controlled by an associated command, control, other electronic or electro-optical countermeas- communications, and intelligence (CSI) system, ures, or A SAT weapons capable of damaging which itself will have three types of subsys- satellites (in which case it would be an A SAT tems, as illustrated abstractly in figure 4-1. weapon system), or both. In general, each First is the intelligence collection part-the weapon would consist of a stand-off weapon space surveillance system—which would de- capable of damaging a satellite at a distance tect electromagnetic radiation emitted or and either carried by a platform such as a sat- reflected by a satellite and, using these meas- ellite, rocket, airplane, or land vehicle, or else urements, attempt to track the satellite and based on the ground at a fixed site. The stand- determine its orbit. Careful interpretation of off weapon could be a kinetic-energy weapon this information may allow characterization (KE W) such as a gun or a fragmentation war- of the satellite-i. e., determination of its mass, head, a directed-energy weapon (DEW) such shape, and other features—and even determi- as a laser or particle accelerator, or an ordi- nation of the function of the satellite. On the nary “isotropic” nuclear warhead (so called be- basis of this interpretation, information would cause it would release roughly equal amounts be communicated over command, control, and of energy in all directions). communications (C3) links to command and control (C*) centers, where authorities would The weapon platform (if any) would carry consider the information in the context of the stand-off weapon to within lethal range of other relevant information and possibly issue a targeted satellite. A highly maneuverable orders to negate the satellite or to interfere platform could pursue and collide with a tar- with its functioning nondestructively (e.g., geted satellite; such a vehicle would be a “hit- using electronic countermeasures). If so, other to-kill” kinetic-energy weapon which would

49 50

Figure 4-1 .—Generic Components of an ASAT System

Sun

Solar radiation

LIDAR or RADAR

not need to carry a stand-off weapon. Alter- added, showing examples of its space surveil- natively, if the stand-off weapon had sufficient lance, command and control, and ASAT weap- lethal range, it would not need to be maneu- on systems. vered toward a targeted satellite but could instead be based on the ground or on a non- Soviet ASAT Capabilities maneuvering platform. Figure 4-2 illustrates a portion of the U.S. Space Surveillance Space Defense System as it will appear when The ASAT capabilities of the Soviet Union the planned anti-satellite weapon system is depend on Soviet space surveillance systems. 51

Figure 4-2.— Illustrative Components of the U.S. Space Defense System

Key: ASATCC: ASAT Control Center (ASAT carrier aircraft base: prelaunch C2) CMC: Cheyenne Mountain Complex MV: Miniature Vehicle (satellite interceptor warhead) NSSC: National Space Surveillance Center PMOC: Prototype Mission Operations Center ROCC: Regional Operations [military air traffic] Control Center (post-launch C2) SPADATS: SPAce Detection and Tracking System SPADOC: SPAce Defense Operations Center WWMCCS: World-Wide Military Command and Control System

The Soviet Union operates extensive military dars used by the Soviet ABM system and ra- and civil networks of radar, LIDAR1, and pho dio telescopes can be used to detect, track, and tographic space surveillance sensors linked to- characterize satellites. The U.S.S.R. also uses gether by satellite and terrestrial communica- ships for satellite tracking and communications systems.2 Soviet missile early warning tions and operates some tracking stations in radars and satellites can detect foreign satel- foreign territory. lite launches. Soviet radio/radar tracking Soviet deep-space detection capabilities nec- ground stations can presumably detect and essarily rely upon passive sensors, primarily track satellites in low-Earth orbit and track telescopic cameras similar to the Baker-Nunn satellites in higher orbits. In addition, the ra- cameras formerly used by the United States and upon radio telescopes and ground-based ‘ LI DAR is an acronym for L Ight Detection And Ranging; s it refers to a radar-like sensor system which transmits pulses military signal intelligence collection systems. of light, typically produced by a laser, and looks for reflections Passive optical sensors, whether photographic from objects. Ranges to objects can be inferred from the time delay of pulses reflected from it. ‘Soviet Space Programs: 1976-80, Part 1, Committee Print, ‘Such systems, which perform direction-finding or signal in- Committee on Commerce, Science, and Transportation, Senate, tercept functions, are called electronic support measure (ESM) 97th Cong., 2d sess., December 1982. IUSGPO 98-515 O] systems. or electro-optical, can detect sunlight reflected believed to be capable of attacking satellites by a high-orbit satellite; the power of the at altitudes up to 5,000 kilometers or even reflected sunlight received by a distant opti- higher, 7 depending on their orbital inclina- cal sensor decreases only as the square of the tions; presumably they would be unable to at- range to the target, so passive optical ‘sensors tack satellites in orbits with unfavorable in- are more useful than radar for detecting high- clinations, i.e., very different from the latitude orbit satellites.4 Similar considerations make of the interceptor launch site. As of 1984 there passive radio systems—i.e., radio telescopes appeared to be only two launch pads for So- or military electronic support measure sys- viet coorbital interceptors, both located at the tems—useful for detection and tracking at Tyuratam launch complex.8 Several intercep- long range, provided the target is emitting a tors could be launched per day from this radio signal of some kind. complex. g It is possible that the U.S.S.R. may develop In 1971 the testing of satellite interceptors electro-optical tracking sensors in the future; was apparently suspended, then resumed in such sensors could provide surveillance infor- 1976, then again suspended in 1978, just be- mation more quickly than can camera systems, fore the U.S.-U.S.S.R. A SAT negotiations be- which require development of photographic gan, then again resumed in 1980 after suspen- film or plates. Neither photographic nor elec- sion of those talks, then again suspended in tro-optical telescopes can detect or track sat- August 1983 when Soviet President Yuri An- ellites from the ground in daytime or through dropov announced a unilateral moratorium on overcast, as radar can. ASAT testing, stating that the U.S.S.R. would not test ASAT weapons if the United Weapons States did not. The U.S.S.R. continues to ob- The Soviet Union has been conducting a ser- serve this unilaterally declared moratorium. ies of tests of coorbital satellite interceptors The U.S.S.R. has never officially and publicly (“killer satellites”) since 1968.5 An artist’s admitted developing or testing weapons of conception of such an interceptor is shown in this type. However, on 29 May 1985, in an in- figure 4-3. The U.S. Department of Defense terview by a West German reporter in Geneva, estimates that these anti-satellite weapons be- Col. Gen. Nikolai Chervov, a senior depart- came operational in 1971.6 These weapons are ment head on the Soviet General Staff, claimed -.— — —.— —. that the U.S.S.R. had successfully developed ‘This is because the energy of a radar return, or “echo,” from a direct-ascent satellite interceptor similar to a satellite decreases as the fourth power of range to the target. Radar returns from satellites in high orbit are generally so weak that tested by the United States in the early that they cannot be detected by a radar rapidly scanning the 1960s and operational until the mid-1970s. sky; they can only be detected if the approximate position of the satellite is already known so that the radar can scan slowly for signals from that general direction, accumulating signal energy for a prolonged period of time. Hence ground-based radar can measure small changes of a high-altitude satellite’s orbit but could not easily find a satellite which had maneuvered energetically since its last observation. Similar considerations limit the effective search range of LIDAR systems. The energy of a radar echo also depends on the radar wavelength used. For example, at wavelengths much longer than a satellite’s diameter, the echo energy decreases rapidly with increasing wavelength-as the inverse fourth power, according to Rayleigh’s law. However, the echo also becomes more omnidirectional (as a consequence of Babinet’s principle and—in the special case of spherical satellites—the Mie effect) and less dependent upon details of satellite shape and composition other ——— than the electric susceptibility of the satellite, in accordance ‘Ibid., p. 56. with Rayleigh’s law. ‘U.S. Department of Defense, Soviet Military Power, 3rd cd., 5U.S. Department of Defense, Soviet Military Power, 4th cd., April 1984, p. 34. April 1985. ‘U.S. Department of Defense, Soviet Mti’tary Power, 4th cd., “ ‘Ibid., p. 55. April 1985, p. 56. Figure 4-3.— The Soviet Coorbital Satellite

Launchpad and storage facility for satelllte Interceptors at Tyuratam

SOURCE U S Department of Defense

The Soviet Union has also been testing based lasers for electro-optical countermeas- ground-based lasers which could have some ures with some effectiveness.ls ASAT capability [see figure 4-4]. The Depart- ment of Defense has stated that the Soviets Operational Capabilities “already have ground-based lasers that could Existing Soviet ASAT capability could be be used to interfere with U.S. satellites. ” As potentially effective for negating low-altitude of 1985, there are two experimental Soviet U.S. MILSATS, such as those used for navi- ground-based lasers with some ASAT capa- gation (Transit) and meteorological surveil- bility, ’O both at Sary Shagan. ” lance (Defense Meteorological Satellite Program In addition to weapons designed specifically satellites). Commenting on this capability, the for A SAT use, the U.S.S.R. could attack low- Honorable Richard Perle, Assistant Secretary altitude satellites with its ABM interceptor of Defense (International Security Policy), has missiles [illustrated in figure 4-4], 12 and pre- stated that: sumably with ICBMS and SLBMS, although We believe that this Soviet anti-satellite ca- these might require some modification for pability is effective against critical U.S. sat- ASAT use. All of these weapons are presum- ellites in relatively low orbit, that in wartime ably armed with nuclear warheads, and their we would have to face the possibility, indeed use in a nonnuclear conflict would be viewed the likelihood, that critical assets of the as escalator by the United States and pre- United States would be destroyed by Soviet sumably by the U.S.S.R. as well. anti-satellite systems, ’4 In addition to these destructive ASAT ca- —. “Ibid., p. 56. pabilities, the U.S.S.R. has a technological ca- “Statement of The Honorable Richard Per]e, Assistant Sec- pability to jam satellite uplinks or downlinks retar~. of Defense ( International Security Policy), in Hearings with some effectiveness, and could use ground- Before the Subcommittee on Strategic and Theater Nuclear Forces of the (’ommjttee cm Armed Serl’ices United States Sen. “’Ihici., p. 56. ate, Testimon?’ on Space Defense illatters in Re\’iew of the “ Ihid., p. 5/+. F1’1 98,5 Defense Authorization Bill [S. Hrg. 98-724], March 15, 121hid., p. 56, 1984, Pt. 7, p. 3452. 54

Figure 4-4.—Soviet Anit.Sateltite Capabilities

.,4- - “ - . —-. + - — .

Soviet high-energy laser facility at Sary Shaaan Two lasers there may be capable of d“amagl ng unprotected satellites at low altltudes

ogies offer greater promise for future anti- satellite application than continued development of ground-based orbital interceptors equipped ‘with conventional warheads, . . . In the late 1980s, they could have prototype space-based laser weapons for use against satellites. In addition, ongoing Soviet programs have progressed to the point where they could include construction of ground- based laser anti-satellite (ASAT) facilities at operational sites. These could be available by Artist’s conception of a Soviet ABM interceptor missile, named the end of the 1980s and would greatly in- GALOSH by Western analysts GALOSH missiles might have capab!litles to attack satellites at low altltudes. crease the Soviets’ laser ASAT capability beyond that currently at their test site at Sary SOURCE U S Department of Defense Shagan. They may deploy operational systems of space-based lasers for anti-satellite purposes in the 1990s, if their technology de- The utility of these U.S. satellites in vari- velopments prove successful. 15 ous types of conflicts is discussed in Appen- dix D to this report, which is a separate, clas- The Soviet Union also has the basic technol- sified document. ogy required to build space-based neutral particle beam weapons. The U.S. Department of Projected Capabilities Defense estimates that: The Soviet Union could develop weapons ca- A prototype space-based particle beam pable of attacking U.S. satellites at higher al- weapon intended only to disrupt satellite titudes than can be reached by the current electronic equipment could be tested in the Soviet coorbital interceptor. Laser weapons, early 1990s, One designed to destroy the satellites could be tested in space in the mid- among other types, could be be used for this 16 7 purpose. The U.S. Department of Defense esti- 1990s. ‘ mates that: i~(j.s, ~epartment of Defense, .sot’iet ,tfi~itarJ power, qth ed., The Soviets are working on technologies or 1985. have specific weapons-related programs under- ‘G I bid. way for more advanced anti-satellite sys- 17 However, as recently as 1984, while projecting this capa- tems. These include space-based kinetic- bility, the Administration noted that Itre have, as ~~et, no evidence of So}’iet programs based on particle-beam technology’ energy, ground- and space-based laser, par- [President Ronald Reagan, “Report to the Congress: U.S. Pol- ticle beam, and radiofrequency weapons. The icy on ASAT Arms C’ontrol, ” 31 March 1984 (u NC I, AS- Soviets apparently believe that these technol- SIFIED~]. 55

Future manned Soviet spacecraft, such as orbit, although some radars can track a satel- the expected Soviet “space shuttle’ ’—and, lite out to geosynchronous altitude if the satel- especially, the “space plane ’’-could have lite’s approximate position is already known.” greater maneuverability and possibly non- The range at which a ground-based radar can cooperative rendezvous capability and, if so, track low-altitude satellites is limited by the some inherent ASAT capability .18 requirement for an unobscured line of sight to the satellite. For example, a satellite at an al- U.S. ASAT Capabilities titude of 185 kilometers (100 nautical miles) would be below the horizon if farther away The U.S. Space Defense System is a network than 1,590 kilometers slant range.20 of systems used for space surveillance and for command and control. An anti-satellite weap- For detection of satellites in deep space the on system will be added to it in the near fu- United States relies on a system of telescopic ture. Figure 4-2 illustrates a portion of the pro- electro-optical sensors called GEODSS, for Ground-based ElectroOptical Deep-space Sur- spective U.S. Space Defense System as it will 2 appear the planned anti-satellite weapon sys- veillance System [see figure 4-6]. ’ The GE- tem is added. The figure shows examples of ODSS network, when completed, will provide world-wide deep-space surveillance coverage the space surveillance, command and control, 22 and ASAT weapon systems which will be part using sensors at five sites : of the U.S. Space Defense System. Socorro, New Mexico (Site I); ● Taegu, South Korea (Site II); Space Surveillance ● Maui, Hawaii (Site III); U.S. ASAT capabilities, like those of the SO . Diego Garcia, in the Indian Ocean (Site viet Union, depend on space surveillance ca- IV); and pabilities. Like the U. S. S. R., the United States ● Portugal (Site V). can use its missile attack warning radars and The main telescopes at each GEODSS facil- satellites to detect satellite launches and can ity are designed to detect objects as dim as track satellites after launch using ground- a star of visual magnitude 16.5, or a reflective based and shipboard radar, LIDAR, passive sphere about the size of a soccer ball in geosyn- optical, and passive radio sensors. The Space chronous orbit. Detection and Tracking System (SPADATS) acquires, processes, stores, and transmits data Command and Control from such sensors, including Naval Space Sur- veillance (NAVSPASUR) radar interferome- Under present policy, the U.S. National ters and Air Force Spacetrack radars and Command Authorities (NCA) would have to Ground-based Electr~Optical Deep-space Sur- authorize satellite negation. Actual opera- veillance System (GEODSS) sensors [see fig- tional control of a negation mission would be ure 4-5]. The United States operates more exercised by the USAF Space Command foreign-based space surveillance facilities than does the U. S. S. R., and consequently relies less ‘eSee note 4, supra. on shipboard systems, although such systems 201. e .!1 ’560, kilometer as projected on the Earth’s surface. are used. A closer satellite at this altitude might be below the horizon, if mountains or other terrain features obscured the view. In addi- The effective search range of U.S. ground- tion, the azimuthal coverage of some radars is limited. 2’D.D. Otten, E.I. Bailis, and J.G. Klayman, “GEODSS: based radar systems is limited to low-Earth Heavenly Chronicler, ” Quest (Redondo Beach, CA: TRW, Inc., August 1980), pp. 3-23. ‘aCurrent manned Soviet spacecraft (Soyuz, Salyut) do not ‘zSites I, II, and 111 are presently operational, and site IV have a significant inherent ASAT capability: they have little should become operational this year. Sites I, II, and III each maneuver capability and have not demonstrated coorbital ren- have two main 40-inch telescopes and one 15-inch auxiliary tel- dezvous with non-cooperative spacecraft. Rendezvous with cm escope, while sites IV and V will have three main telescopes operative spacecraft is typically performed by an automatic sys- each. Site equipment is designed to be relocatable within 2 tem which relies on a transponder on the passive spacecraft. weeks. 56

Figure 4-5.—Space Detection and Tracking System

0 30 60 90 120 150 180 210 240 270 300 330 360 ■ Radar .Electro-optical (GEODSS) SOURCE The Aerospace Corp

Space Defense Operations Center (SPADOC) Weapons in the Cheyenne Mountain Complex using In 1959 the United States successfully in- other assets of the Space Defense Command 29 tercepted the Explorer VI satellite using an and Control System [see Figures 4.7 and 4.8]. air-launched ballistic missile developed for On October 1, 1985, satellite negation will other purposes and, the following year, began become the responsibility of a new unified to develop—but abandoned before testing—a space command which will also exercise oper- coorbital SAtellite Interceptor system (SAINT) ational command over U.S. military space sys- designed specifically for the purpose of in- tems which provide support to the combatant specting and destroying satellites. The United forces of other unified and specified com- States also maintained an operational direct- mands. Creation of a unified space command ascent satellite interceptor capability from was proposed in order to increase the effective 1963 until 1975, using nuclear-armed Nike- ness and responsiveness of U.S. space systems Zeus missiles (Project Mudflap, 1963-1964) and to ensure a clear chain of command from and Thor missiles (Project 437, 1964-1975).25 24 the NCA to combatant forces. Creation of the The United States has no deliberate opera- U.S. Space Command was authorized by the tional ASAT capability at the present time, President on November 30, 1984. although its nuclear-armed ICBMS and SLBMS have some inherent ASAT capabilities, as was 2SR.S. Cooper, Director, Defense Advanced Research Projects demonstrated by the nonnuclear exoatmos- Agency, The U.S. Anti-sate fi”te (ASAT) Program, statement pheric ABM Homing Overlay Experiment before the Senate Foreign Relations Committee, 25 April 1984. Z4Hon. Verne Orr, Secretary of the Air Force, USAF FY85 Report to the 98th Congress of the United States of America, “M. Smith, “Anti-satellites (Killer Satellites), ” CRS Issue 8 February 1984; reprinted in S. Hrg 98-724. Brief 1B81123, 22 August 1983. 57

Figure 4-6.—Deep Space Surveillance Systems

Left: Today, surveillance of deep space IS performed by ground-based electro-optical surveillance systems such as the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) system, which IS operated by the U.S. Air Force Space Command as part of the Space Detect Ion and Tracking I System (SPADATS) Here, an operator at a GEODSS control and display console studies a 21 field of view of deep space. On a clear night, a GEODSS main telescope can automatical- ly survey over 500 such fields per hour and detect reflective satellites as small as soccer balls at geosynchronous altltudes

SOURCE U S AIr Force 58

Figure 4-7.—ASAT Mission Operations Concept

ASAT Control Center

Tyndall AFB SE ROCC

This illustration shows communication links which would be used for a satellite negation operation.

SOURCE: The Aerospace Corp

(HOE) test of 10 June 1984. However, the U.S. which provide missile attack warning, navi- Air Force is flight-testing an air-launched, gation, and advanced communications func- direct-ascent anti-satellite weapon called the tions.27 Miniature Vehicle (’(MV”). This infrared- guided nonnuclear kinetic-energy weapon [see The Air Force plans to hold 12 flight tests figure 4-9] is mounted on a two-stage SRAM/ of the ASAT system. Two of the twelve tests ALTAIR booster which is carried aloft and have been held–the first in January 1984 and launched from an F-15 aircraft. F-15 carrier the second in November 1984. In the January aircraft are to be deployed at Langley Air test, the ASAT missile was targeted at a point Force Base in Virginia and at McChord Air in space to determine whether the two-stage Force Base in Washington state [see figure 4- SRAM/ALTAIR booster could deliver the 10]. When operational, it will be able to attack miniature homing vehicle to the vicinity of the low-altitude Soviet satellites which perform target point. The Air Force considered the test reconnaissance and targeting functions; these a success: the proper functioning of the first are viewed as most threatening by the United and second stage propulsion systems and the States. 28 If based as planned, these weapons will not be able to attack Soviet satellites 2’R.S. Cooper, Director, Defense Advanced Reeearch Projects ‘“President Ronald Reagan, l?epmt to the Congress: U.S. Pol- Agency, The U.S. Anti-satelh”te (ASAT) program, statement icy on ASATArms Control, 31 March 1984 ~NCLASSIFIED]. before the Senate Foreign Relations Committee, 25 April 1984. 59

Figure 4-8.— Mission Control Events

— kxecution of a satellite negation mission using the USAF MV ASAT weapon would begin with an alerting order. The target would then be tracked by SPADATS and its ephemeris would be updated by the National Space Surveillance Center (NSSC) for use in generating mission tapes to be loaded on the carrier aircraft for targeting of the ASAT weapon. After an execution order is issued from the Prototype Mission Operations Center (PMOC) in the Cheyenne Mountain Complex (CMC), the carrier aircraft would take off and the missile would have to be launched before sensor coolant exhaustion. Before missile launch, the carrier aircraft would receive updated information and instructions by high-frequency radio data link from a Regional Operations Control Center (ROCC), which is an element of the current military air traffic control center.

SOURCE The Aerospace Corp missile guidance system was successfully dem- The Air Force considered the test a partial suc- onstrated. 28 cess. zg The objective of the November 1984 test Successful completion of U.S. ASAT tests was to reaffirm the performance of the mis- would provide confidence that the weapon sile and to demonstrate the capability of a min- could perform as specified if actually used. iature homing vehicle to acquire and track an Funds for completion of the planned flight test infrared-emitting body (in this test, a star) program have been appropriated by Congress against the radiant background of deep space. subject to certain limitations, partly because of concern that once the weapons are proven — effective, the Soviet Union would cease to ob- 2’U.S. Congress, General Accounting Office, “Report to the serve its self-imposed moratorium on the test- Honorable George E. Brown, Jr., House of Representatives: Sta- and might be reluc- tus of the U.S. Antisatellite Program, ” report GAO/NsIAl)- ing of ASAT weapons 85-104, June 14, 1985. “Ibid. 60

USAF

ASAT missile carried by F-15 fighter during refueling operation

SOURCE U.S Alr Force 61 ———. —— ——— —— . —

Figure 4-.10. —ASAT Mission Profile

Target satelIite

vehicle homing } intercept

Upper stage pointing and target } acquisition

Missile guidance to intercept point in space

Targeting data loaded by ground \ support equipment

SOURCE The Aerospace Corp tant to agree to arms control measures which States retained a capability to use hidden would ban them. Because the small weapons ASAT weapons. could be easily concealed, if they are proven effective and then banned by agreement, So- The estimated costs of the U.S. ASAT pro- viet authorities might suspect that the United gram are listed in table 4-I. 62

Table 4.1 .—Estimated Costs of the U.S. Air Force Space Defense and Operations (ASAT) Program

POSSIBLE ADVANCED-TECHNOLOGY ASAT WEAPON SYSTEMS

It will be possible in a few years to build Table 4-2 lists the major categories of ASAT space surveillance systems, ASAT weapon weapons, organized, according to physical systems, and ASAT countermeasure systems means of causing damage, into three catego- much more capable than those used by the ries: isotropic (nondirectional) nuclear weap- United States or expected to become opera- ons, kinetic-energy weapons (projectiles), and tional soon. These advanced systems could use directed-energy weapons (particle beam weap- technologies expected to be available eventu- ons, radio-frequency weapons, and laser weap- ally in both the United States and the Soviet ons). Because the boundary between destruc- Union. The variety of possible systems is so tive directed-energy devices (weapons) and great that this report will discuss only those nondestructive directed-energy devices (e.g., which seem most promising or threatening radio jammers, lasers used to overload opti- with respect to criteria of responsiveness, sur- cal sensors, or particle-beam generators used vivability, altitude reach, economy, early avail- to upset the functioning of electronic systems) ability, controllable lethality (for destructive is blurred, being one of power or mode of use applications), and usefulness at nonnuclear rather than kind, nondestructive directed- levels of conflict. The most promising ASAT energy devices will not be distinguished from technologies will be discussed in this section directed-energy weapons except where nec- as possible U.S. options. Space surveillance essary. systems, although essential components of space defense systems, will not be discussed Isotropic Nuclear Weapons in this section, because the most promising space surveillance technologies would be used Ordinary nuclear weapons, when detonated to best advantage in space-based space sur- in space, radiate energy and disperse debris veillance systems; these were discussed in more or less uniformly in all directions. Hence chapter 3 as possible advanced-technology they will be called isotropic nuclear weapons MILSAT capabilities. (INW) to distinguish them from nuclear explo- 63

Table 4-2.—Types of ASAT Weapons hibited by the Outer Space Treaty of 1967. Moreover, existing U.S. procedures for safe- Isotropic nuclear weapons (/NW): Ground-based guarding nuclear weapons and for preventing —Coorbital interceptor their unauthorized use are expensive and time- —Direct-ascent (“pop-up”) interceptor consuming, and the Soviet Union may have Space-based —Coorbital interceptor (nuclear ‘{space mines”)’ b similar safeguards now and incentives to re- Kinetic-energy weapons (KEW): tain them in the future. On the other hand, the Ground-based advantages of isotropic nuclear weapons are —Coorbital interceptor —Direct-ascent (“pop-up”) interceptor their present availability, their economy (rela- Space-based tive to other weapons of comparable range), —Coorbital interceptor (“space mines”)’ their concealability (from present surveillance —Noncoorbital interceptor Directed-energy weapons (DEW): systems), their great lethal range (as compared Ground-based to kinetic-energy weapons) against unhar- —High-power radio-frequency (HPRF) and active dened satellites, the difficulty of hardening electronic countermeasures (ECM) —High-energy laser (H EL) and active electro-optical satellites against nuclear detonations at close countermeasures (E-OCM) range, and their adaptability for delivery by Space-based a variety of launch vehicles and orbital plat- —High-power radio-frequency (HPRF) and active electronic countermeasures (ECM) forms, including those with poor guidance ac- —High-energy laser (HEL)d and active electro-optical curacy and no pointing capability. countermeasures (E-OCM) —Neutral-particle beam (NPB) By comparison, nuclear directed-energy aA “space mine” Is an expendableASAT weapon predeployed In space so as weapons are not now available and, if devel- to be capable of destfoy!ng enemy satellites almost Instantly They could be armed wtth INW, KEW, or DEW I f armed with a short-range weapon, a space oped, would require platforms with moder- mine must be coorbital bprohibited by the 1967 Outer space Treaty ately accurate pointing capability. However, Clntercepis targets at high velocity from parking orbit dlnc[udlng nuclear explosive powered X.ray lasers (X RLS), Which are nuclear it is possible in principle to build nuclear directed-energy weapons (NDEW) directed-energy weapons, such as X-ray lasers, which could have far greater lethal range than sive-powered directed-energy weapons (NDEW) the nuclear explosive devices which power which will be discussed subsequently. INW them and which could be feasibly and economic- could be carried to within lethal range of a sat- ally delivered by platforms with adequate ellite or satellites by a rocket and detonated. pointing capability. The theoretical potential Early U.S. ASAT weapons were of this type, of such weapons,34 if realized in practice, would and the United States or the U.S.S.R. could make them superior to isotropic nuclear weap- use nuclear-armed ICBMS, SLBMS, and ABM ons for ASAT applications. The potential interceptors in this manner. Alternatively, ASAT capabilities of NDEW, therefore, de- INW could be used as nuclear space mines: serve greater concern than do those of iso- they could be concealed aboard satellites tropic nuclear weapons which are, however, of which are continuously or occasionally within more immediate concern because of their ex- lethal range of enemy satellites and detonated istence and demonstrated capability. on command. Existing nuclear-armed Soviet ABM mis- As ASAT weapons, nuclear weapons have siles could be used against low-altitude satel- several legal, political, and strategic disadvant- lies. Prior testing of such weapons against sat- ages: they can only be used at the nuclear ellites would not be required to demonstrate level of conflict-or in any case their use would the reliability of subsystem operation. escalate a conflict to the nuclear level—and when used they may upset or damage unhardened friendly and neutral satellites at “See, e.g., F.V. Bunkin, V.I. Derzhiev and S.1. Yakovlenko, ranges which depend on weapon yield but ‘‘Specification for pumping X-ray laser with ionizing radiation, ” Soviet Jourmd of QuantxJrn Electronics, vol. 11, No. 7, July which can be very large. In addition, they can- 1981, pp. 971-972, and note that many such lasers could be pow- not legally be based in orbit, this being pro- ered by one “exotic” source of pulsed x-radiation. 64

Isotropic nuclear weapons concealed aboard The risk which such weapons may pose to satellites used as ‘‘space mines” could attack U.S. spacecraft now or in the future is miti- without warning and would pose a greater gated to some extent by the fact that they

threat+ because reactive countermeasures could would be useful only in a nuclear war, in which not be used for protection. Nuclear space the ground segments of space systems would mines could be lethal against satellites as hard also be significantly vulnerable and might be as any now operational at such range that the attacked by preference, and more rapidly. This testing of their trailing capability -e.g., in ge- and the other aforementioned disadvantages ostationary orbit—although observable, might of ASAT INW pose disincentives against de- not be interpreted as such. Protection against veloping them, attempting to base them in or- such weapons would require evading them bit covertly, and using them at nonnuclear during placement (which would be relatively levels of conflict economical only for a small, cheap satellite), Several conclusions follow from these con- opposing their placement by defending an siderations: agreed or unilaterally declared “keep-out zone” around satellites from penetration by 1. It is feasible to build direct-ascent and any spacecraft which might contain a nuclear coorbital isotropic nuclear weapons. weapon, or possibly, after penetration and 2. Weapons of this type could be as small trailing by such a spacecraft, evading (e.g., un- and inexpensive as many existing sat- der cover of smoke and chaff) it until out of ellites. its probable lethal range, at which time it could 3. Such weapons could be developed and be attacked by ASAT weapons of greater tested covertly. range, if available. 4. Soviet nuclear weapons could threaten U.S. satellites at low and high altitudes Development and, when necessary, opera- now and in the future but only at nuclear tion of closelook inspection satellites equipped levels of conflict. with gamma-ray spectrometers or other in- 5. Protection of U.S. satellites from coorbi- struments capable of detecting materials used tal INW may require defense of a keep- in nuclear explosives would afford additional out zone around low-altitude satellites or protection: if inspection by such satellites were designing future low-altitude satellites to anticipated, the designer of a nuclear space beat least as small and inexpensive as the mine would have to shield its nuclear explo- g5 nuclear space mines which threaten them. sive device with tons of material in order to Many more options are available for de- prevent collection of prima facie evidence of fending high-altitude satellites from di- having placed a nuclear weapon in orbit in vio- rect-ascent nuclear interceptors. lation of the Outer Space Treaty of 1967. Plac- ing so massive a space mine into orbit would be more costly, and it could be evaded at less Kinetic-Energy Weapons relative cost than a smaller, unshielded space Anti-satellite kinetic-energy weapons pursue mine could be. satellites and destroy them by direct impact or at close range using a gun or a fragmenta- “U.S. and Soviet scientific spacecraft, landers as well as or- tion warhead. One example of an ASAT KE W biters, have carried gamrn a-ray spectrometers capable of de- is a coorbital interceptor which approaches its tecting low concentrations of fissionable materials as deep as half a meter below lunar and planetary surfaces [U.S. National target at a low closing velocity before destroy- Aeronautics and Space Administration, A Forecast of Space ing it. Another example is a direct-ascent Technology 1980-2000, NASA Special Report SP-387, 1976; and (“pop-up”) interceptor which is launched from cf. the recent Soviet “VEGA” Venus/Halley’s Comet probe.]. The United States could develop such sensors for use on satel- the Earth’s surface or from an airplane and lites for purposes of monitoring compliance with the Outer which approaches its target at a high closing Space Treaty. velocity. Such an interceptor could also be 65 based in space in a parking orbit, from which armored satellites as small as about a meter it could enter a transfer orbit in which it would in diameter with high probability. The pellets close with its target at high velocity, just as for such a warhead would weigh 100 kilo- a pop-up interceptor would. “Pop-up” inter- grams, and its explosive charge could weigh ception requires less energy per unit intercep- less than that. Even lighter warheads of this tor payload than does coorbital interception, type may be possible, possibly having disper- particularly at low altitudes. A coorbital in- sion angles as small as those of shotguns or terceptor, on the other hand, could be used as even high-power rifles (e.g., 10 centimeters dis- a “space mine, continuously observing and persion at a range of 1 kilometer). trailing its target, prepared to destroy it Guns and rockets could also be used as ar- almost instantly on command or (if salvage- mament by a KEW space mine. For example, fused) when attacked or disturbed in specified a single unguided rocket which deploys a 10 ways. Used in this way, a coorbital ASAT x 10 meter net weighing about 1 kilogram and KEW could take advantage of the element of having a l-gram weight at each of its 100 surprise in an attack, leaving an enemy no nodes (knots) could achieve the same kill prob- time to react with active defenses or reactive ability as the Claymore-type warhead if its passive countermeasures such as evasion or aiming error were less than 5 milliradians (5 deployment of decoys or smoke. meters at 1 kilometer) after rocket burnout A coorbital interceptor could pursue a tar- and net deployment. A space mine using such get (its ‘quarry”) indefinitely if it had as much a rocket as armament might weigh as little as velocity change capability (“delta-V”) as its 50 kilograms but could destroy much heavier quarry. If it also had as much acceleration ca- unhardened satellites. pability as its quarry, it could, with tracking It would not be relatively economical to use capability, pursue its quarry continuously, such mines to attack smaller, cheaper satel- otherwise its quarry would be able to maneu- lites, which could be useful for some military ver out of lethal range temporarily. Under 37 applications, such as communications. How- some conditions, an interceptor may be able ever, it would be economical to use space to trail its quarry using less delta-V than its mines to attack larger satellites. If such sat- target uses for evasion; however, calculation 3G ellites are armored as a countermeasure, the of required velocity change is complicated, space mine could also be made more lethal, and particularly in the case of many-against-one this would probably require less mass than interception. In any case, if comparable pro- would be required for armor against it at the pulsive technologies are available to both pur- assumed lethal range38. There appears to be suer and evader, pursuit can be successful if no relatively economical means of protecting the interceptor’s mission payload—its arma- large satellites against a surprise attack by ment (if any) and guidance and fuzing sys- such mines, once they are emplaced. Safety tems—is lighter than that of its quarry. from such attacks would require opposing It should be possible to build space mines their placement by defending an agreed or uni- with very lightweight armament. For exam- laterally declared “keep-out zone” around sat- ple, a directional fragmentation warhead sim- ellites, or else, once they are emplaced, evad- ilar to that of a Claymore mine could project ing them (e.g., under cover of smoke and chaff) 100,000 one-gram pellets in a pattern which until out of their range, at which time they would cover a 100 x 100 meter area with 10 could be attacked by ASAT weapons of greater pellets per square meter at a range of 1 kilo- range. meter. This would be adequate to destroy un- s~For example, the U.S.S.R. operates a constellation of Mht- weight satellites in low orbit, and as early as 1961 the United ‘G.M. Anderson, “Differential Dynamic Progr amming Feed- States operated SYNCOM communications satellites weighing back Control for a Pursuing Spacecraft with Limited Fuel, ’’(New only 31 kilograms in geosynchronous orbit. York, NY: American Institute of Aeronautics and Astronau- 98s= the di~Cu99iOn Of har&ning in the discussion Of Coun- tics, AIAA Paper A78-31925, 1978). termeasures, below. Space mines the size of those assumed (2 satellites or designing future satellites to be meters in diameter) could be detected by at least as small and inexpensive as the space ground-based radars if at low altitude or, if at mines which threaten them. high altitude, by electro-optical sensors (e.g., GEODSS) if they do not employ measures Directed-Energy Weapons (e.g., black paint) to evade detection or by space-based long-wavelength infrared space Several types of directed-energy weapons surveillance sensors even if they do employ could be used for ASAT purposes, including such measures. In order to demonstrate relia- ground- and space-based systems powered by bility, they would have to be tested in space nuclear explosives, nuclear reactors, or non- by trailing satellites or space debris. This nuclear energy sources. They include high- activity could be observed and would be no- power radio-frequency (HPRF) generators, ticeable. high-energy laser (HEL) weapons, and neutral particle beam (NPB) weapons. They could also The U.S. Department of Defense has esti- include non-laser sources of short-wavelength mated that the U.S.S.R. views development radiation. of directed-energy weapons as a more promising approach for improving future antisatel- High-Power Radio-Frequency Weapons and lite capabilities than further development of Electronic Countermeasures ground-based kinetic-energy ASAT weapons.39 However, Soviet development and testing of HPRF weapons–which include high-power interceptors of the type which is currently microwave (HPM) weapons—are devices capable of producing intense, damaging beams of operational have demonstrated an interest, 4 and some capability, in coorbital, nonnuclear radio-frequency radiation. 1 HPRF generators kinetic-kill approaches to ASAT capability. could be used to overload and damage satel- Given sufficient incentive, the U.S.S.R. might lite electronic equipment at high power levels choose to continue these efforts and, if so, or, at lower power levels, merely to temporar- could eventually produce smaller, cheaper ily overload satellite electronic systems (i.e., weapons of longer endurance. Once testing of for “jamming“).” Radidrequency (RF) gener- such weapons in space is observed, there ators could therefore be useful at all levels of might be insufficient time for the United conflict. States to react by developing new generations HPRF weapons could be ground-based or of small, inexpensive satellites against which based in space. Ground-based HPRF weapons, use of small space mines would be uneconom- unlike ground-based laser weapons, could oper- 40 ical. ate through cloud cover. However, the maximum pulse energy per unit area which can be It can be concluded from these considera- 4s tions that it is feasible to build coorbital beamed through the atmosphere is limited. kinetic-energy ASAT weapons. Weapons of Space-based HPRF weapons would not be so this type could be smaller and cheaper than limited, but, like ground-based HPRF weap- most satellites as presently designed. If such weapons are deployed by the U. S. S. R., pro- 4’I.e., electromagnetic radiation at wavelengths of 1 rnillim~tir tecting future U.S. satellites from them may or longer, ‘This continuum of HPRF effects makes distinction between require defense of a keep-out zone around U.S. “weapons” and “j ammers ” diffimk.. For arms control purposes, however, a distinction could be made based on power-aperture product, as is done in the ABM IYeaty. Wavelengthdependence ‘U.S. Department of Defense, Sow”et Military Power, 4th cd., should be considered as well, because at a given power-aperture Apd 1985, p. 44. product, shorter wavelengths can be radiated with greater ● OFor exmple, ~viet testing of interceptors Of the tYPe now brightness and deliver more power per unit area at long range. operational was first observed in 1968, and the U.S. Depart- 4The maximurn p~se energy per unit area which can be ment of Defense has judged, in retrospect, that an operational beamed through the atmosphere is limited to about 1 jo~e per capability with these interceptors was achieved three years square meter by the phenomenon of dielectric breakdown of the later, in 1971. [Ibid,, p. 55.] atmosphere, which occurs at higher energy fluence levels. 67 ens, would have to be very large in order to electronic counter-countermeasures, when nec- concentrate their HPRF energy into a narrow essary, would be preferred. beam. Even a relatively wide beam might be able to damage satellites of existing designs High-Energy Laser Weapons and Electro- at considerable range, but this is uncertain, Optical Countermeasures (Ground-Based) and hardening satellites against HPRF radi- High-energy laser weapons are devices ca- ation is possible. pable of producing intense, damaging beams 45 The lethality of HPRF weapons would be of optical radiation by means of the phenome less certain than the lethality of other DEW non of stimulated emission of radiation. High- because of uncertainties about target vulner- energy lasers could be used to permanently ability, i.e., about the beam energy per unit damage satellites, or, at lower power levels, area required to damage a particular enemy to jam optical communication systems and to satellite, This will depend on details of the de- “dazzle” optical sensor systems (i.e., to over- sign of the satellite and would be difficult to load them, temporarily blinding them). This predict with accuracy even if those details continuum of effects makes the distinction be were known. Moreover, even though it is pos- tween “laser weapons” and “active electro- sible in principle to harden satellites to with- optical countermeasures” one of degree rather 46 stand intense HPRF radiation, it is difficult than kind and therefore difficult. Lasers of to verify by modeling and simulation, and ex- several types, employing different materials orbitantly expensive to verify by testing, the and physical processes and operating at differ- actual degree of hardness achieved. Hence, al- ent wavelengths, might be suitable for use as though many concepts for HPRF weapons weapons; some of these types are described in have been studied, none of them are as resis- the box entitled “Types of Lasers. ” tant to countermeasures as are some HEL and HEL weapons could be space-, ground-, air-, neutral particle beam concepts. or sea-based. Of the many possible types of Radio-frequency generators of lower power lasers useful as ground-based A SAT weapons, will continue to be valuable for providing ca- continuous-wave deuterium-fluoride chemical pabilities to jam and spoof (i.e., deceive) sat- lasers have been of particular interest because ellite radio systems.44 The vulnerability of sat- of their simplicity, the maturity of their tech- ellites to jamming and, especially, spoofing, nology, and the possibility of focusing their is also uncertain and probably varies greatly infrared beams using mirrors of relatively among satellites. However, low-power RF rough surface quality (compared to that which generators useful for jamming and spoofing would be required at shorter visible and ultra- would be much cheaper than HPRF generators; violet wavelengths). indeed, some existing electronic countermeas- Repetitively-pulsed free-electron lasers and ure systems could be used against satellite electric-discharge excimer lasers have also links. Because of the prevalence and ambigu- been of interest because they would operate ity of these capabilities, it would be difficult at short wavelengths at which small beam or impossible to eliminate the non-destructive divergence angles could be achieved using A SAT capabilities of ECM systems by means smaller mirrors than would be required for in- of arms control agreements. Use of passive frared beams, although they would have to be . ‘Jh;t’en at ~er~’ low power le~rels radio-frequency genera~ors — might be able to confuse (’‘spoof’ satellites b~ beaming de- “I. e., electromagnetic radiation at ~a~’elengths shorter than cepti;”e signals at them. Some possible spoofing techniques ha~’e 1 millimeter, been described b~’ CO1, Robert B. Giffin, (JS~\ F. in [JS Space ‘fi For arms control purposes, howe~er, a distinction could be ,$~,sten] SurIiLabilitjr: Strategic .A)ternacil’es for the 1990s, Na- made based on power-aperture product, as is done in the ABM tional Securit~ Affairs Nlonograph Series 82-$, National 1)e- Treat~’. \$’a\elength-dependence should be considered as well, fense [[ni\ersit?’ Press, F’ort I,eslie ,J. LlcNair, W’mhington, DC, because at a git’en power-aperture product, shorter wa~’elengths 19X2: p. 26. E;lectrwnic counter-counterlmeasures can be used can he radiated with greater brightness and delit’er more power to reduce the ~usceptibilit~ of hl I I,SATS to spoofing. per unit area at long range. 68 —

Types of Lasers A laser is described by the lasant material it Such molecules are called excimers, a contrac- uses as a source of coherent optical radiation tion for “excited dimer” (a dimer is a molecule (e.g., deuterium fluoride), the characteristic consisting of two atoms). wavelength or wavelengths at which the lasant emits such radiation, the method of pumping Free-electron lasers do not use lasants but in- (i.e., energizing) the lasant (e.g., chemical lasers, stead generate radiation by the interaction of electric-discharge lasers, optically pumped an electron beam with a static magnetic or elec- lasers, gasdynamic lasers, etc.), the source of tric field. Loosely speaking, free-electron laser energy used for pumping (e.g., chemical electri- technology resembles and evolved from that cal, nuclear reactor, nuclear explosive, etc.), and used by particle accelerators (“atom smash- its pulse waveform (e.g., single-pulse, repeti- ers”), while other (i.e., bound+lectron) lasers use tively pulsed, or continuous-wave). Iasants heated by electrical current or chemical combustion and resemble fluorescent lamps or Many materials can be used as lasants; these rocket engines in some respects. Some lasers can be in solid, liquid, or gaseous form (consist- use mirrors, lenses, diffraction gratings, or ing of molecules or atoms) or in the form of a other optical elements to recirculate the laser plasma (consisting of ions and electrons). beam through the lasant in order to achieve ade- Lasant materials useful in highnergy lasers in- quate amplification; such lasers are called clude carbon dioxide, carbon monoxide, deu- cavity lasers, and the arrangement of optical terium fluoride, hydrogen fluoride, iodine, xenon elements used to recirculate the beam is called chloride, krypton fluoride and selenium, to men- the laser cavity or resonator. In other lasers, the tion but a few, Some of these-e.g., xenon chlo- beam passes through the lasant only once; such ride and krypton fluoride-are molecules which cavity-less lasers are called superradiant lasers, cannot exist under ordinary conditions of ap- and the process of singk+pass beam generation proximate thermal equilibrium but must be cre- they use is called superradiance, superfluores- ated by special “pumping” processes in a laser. cence, or amplified spontaneous emission.

of higher optical quality. Free-electron lasers Beams from ground-based HEL weapons can probably be ‘made more efficient than would be subject to a variety of phenomena other short-wavelength lasers and could be which would disturb their propagation through ground- or space-based. Electric-discharge ex- the atmosphere. These phenomena include ab- cimer lasers might be available sooner, but sorption, scattering, thermal blooming, dielec- probably cannotbe made as efficient as free- tric breakdown, and the refractive effects of electron”lasers can be, nor can they be tuned, atmospheric turbulence. Most serious is beam as free-electron lasers can be, to wavelengths absorption and scattering by clouds: ground- which would minimize beam degradation by based HEL weapons, unlike ground-based atmospheric effects (in the case of ground- HPRF weapons, could not operate through based ‘lasers) and optimize target damage.47 cloud cover.48

“Soviet laser development has emphasized other technologies than these; the “best” laser technologies for near-term Soviet weapons may differ from those which would be ‘‘best” for near- —.—— term U.S. weapons. Cf. N.N. Sobolev and V.V. Sokivikov, “The ‘*Dielectric breakdown is not as serious at optical wavelengths Carbon Monoxide Laser: Review of Experimental Results, ” So as it is at radio wavelengths. Scattering causes beam degrada- vie.t Jourmd of Quantum l?~ectronics, vol. 2, Jan. -Feb. 1973, p. tion, especially at short wavelengths, but is not insurmounta- 305 ff.; M.M. Mann, “CO Electric Discharge Lasers, ” AIAA bly problematic in clear weather. Thermal blooming of a beam Journal, vol. 14, No. 5, May 1976, pp. 549-567; A.A. Stepanov focused on a distant satellite can be controlled by phase com- and V.A. Schlegov, “Continuous-Wave Reaction-Product Chem- pensation techniques, or by using a laser which operates at a ical Lasers (Review), Soviet Journal of Quantum Electronics, wavelength at which atmospheric absorption is not severe. A vol. 12, No. 6, June 1982, pp. 681-707; and S. Kassel, Soviet deuterium fluoride laser, for example, operates at such a wave-

Free-Electron ~J~ser Research {Santa Monica, CA: The Rand length and future freeelectron lasers could also operate at such Corporation, report R-3259-ARPA, May 1985); wavelengths. 69

The effects of atmospheric turbulence also High-Energy Laser Weapons and Electro- pose a serious problem for ground-based lasers: Optical Countermeasures (Space-Based) without compensation, the beam of a ground- The beams of space-based laser weapons based laser would diverge at so great an an- would not have to pass through the atmos- gle that it would be unable to damage any- phere and could damage unhardened satellites thing other than the most sensitive earth- at great range. A much smaller force of such pointed optical sensors on satellites at geosta- lasers than would be required for effective bal- tionary altitude. Such compensation appears listic missile defense could pose a threat to a possible, in principle. nation’s most critical satellites. However, Another serious problem for ground-based space-based laser weapons, like other satel- lasers is the infrequency with which a low- lites, would be subject to attack by ASAT altitude satellite would pass within view of a weapons. ground-based laser site. The interval between Several types of lasers could be used as such passes might be days or weeks, and, until space-based laser weapons, each having some it exhausted its maneuver fuel, a maneuver- particuhu- advantage. For example, of those ing satellite could completely avoid coming lasers which could damage satellites by over- within range. Deployment of a large number heating them, hydrogen-fluoride chemical of ground-based lasers would provide more fre lasers are particularly attractive because of quent opportunities to engage satellites and their simplicity, while carbon-monoxide elec- would increase the difficulty and expense of tric-discharge lasers are attractive because of evasive maneuver and of attempts to attack their potentially high electrical efficiency. the laser sites. It would also increase the prob- Free-electron lasers are attractive because ability that a number of the lasers would not they can operate at short wavelengths at be overcast by impenetrable cloud cover. Of which small beam divergence angles can be course, such proliferation would be expensive. achieved using small mirrors. Excimer lasers An alternative approach would be to base would be bulky and less suitable for space ASAT lasers on ships, which would have some basing. flexibility to remain in clear weather near the Space-based lasers of very low power, if of ground tracks of high-priority targets and dis- an appropriate wavelength, could dazzle or tant from most anti-shipping threats. Another permanently blind optical sensors used by solution to the coverage problem would be to other weapons for homing guidance or for deploy steerable reflectors on satellites to re- beam pointing. More powerful lasers could be lay the beams from ground-based lasers to tar- used to attack and damage a satellite by over- gets or to other relay satellites. The opera- heating it and possibly melting its “skin,” or tional capabilities provided by such a system tearing its “skin’ as a result of the hammer- would be similar to those provided by space- like mechanical impulse which pulsed laser ra- based laser weapons with an unlimited power diation can generate on a target surface.4g supply, except that beam availability would -————. --—— be contingent on the absence of overcast at igThe amount of mechanical impulse which a Aven amOUnt of beam energy can generate can be estimated on the basis of at least one ground-based laser site and on the published impulse-coupling models, such as that of P.E. Niel- survival of both a ground-based laser and an son, “High-Energy Laser-Matter Coupling in a Vacuum, ” Jour- orbital reflector. nal of Applied Ph~wics, vol. 50, No, 6, June 1979, pp. 3938-3943, modified to account for the depth to which the beam radiation A high-altitude satellite, on the other hand, will penetrate before surface ~aporization begins. In Directed Energy hfissile Defense in Space IOTA Background Paper OTA- would be within view of a ground-based laser BP-l SC-26, April 1984], Dr. Ashton Carter estimated that a la- site for a prolonged or indefinite period. For ser beam fluence of 20 kilojoules per square centimeter would example, a ground-based laser could irradiate produce an impulse intensity of 10 kilotaps [10,000 dyrwseconds per square centimeter], i.e., an impulse coupling of 0.5 dyne- a satellite in geostationary orbit continuously, seconds per joule. This estimate assumes that the laser pulse weather permitting. is so brief that little heat is conducted to a depth greater than 70 — —

Spacebased reflectors could relay beams from another laser, a nuclear explosion, or some ground-based lasers to a target, or another other source. The beam from such a device reflector, beyond the horizon. These could be would diverge at an angle roughly equal to the used in much the same manner as space-based square root of its wavelength divided by the lasers and would be, in effect, space-based square root of the length of the fiber.5] lasers with an unlimited fuel supply. The U.S. Department of Energy is investi- All of these weapons have certain disadvan- gating the feasibility of developing nuclear- tages, however. They would use large, expen- pumped X-ray laser weapons. Nuclear explosive, power-handling mirrors; they would en- sive pumping is of interest because even if only gage targets sequentially, thus giving other a small fraction of the energy of a nuclear ex- enemy satellites time to use reactive passive plosion could be converted into X-ray laser countermeasures (e.g., smoke); and they would beams, it could still be lethal at great range. be subject to attack by expendable, singleshot Most details of this research, except for the weapons (INW, KEW, or DEW) against which fact of its existence, are classified. However, reactive countermeasures and shoot-back would the U.S. Department of Energy has stated be ineffective. Hence space-based lasers which that: can damage one or several targets instantly, 1. The U.S. Department of Energy is inter- without warning, using a single pulse and ested in and is conducting research on cer- which are cheap enough to be considered ex- tain types of nuclear explosive powered pendable, if feasible, would be most attractive. directed-energy weapons (NDEW)–viz., Because they would exhaust their fuel or de- X-ray lasers, visible-light weapons, micro- stroy themselves as soon as they were used, wave weapons, and charged-particle beam they would be invulnerable to shoot-back al- weapons—as well as on nuclear explosive though subject, and possibly vulnerable, to powered kinetic-energy weapons (NKE W). preemptive attack. 2. Underground nuclear tests at the Nevada One type of laser which might be useful as Test Site have been and continue to be a an expendable, single-shot, space-based weap- part of this research. on is the X-ray laser. X-ray lasers are presently 3. NDEW could engage multiple targets only in the earliest stages of development.50 using multiple beams, providing high X-ray lasers (also called “x-rasers” or XRLS) leverage. could be very simple in design; they might 4. NDEW could damage targets at ranges be thin fibers of lasing material powered of thousands of kilometers. (“pumped”) by intense, pulsed radiation from 5. Nuclear explosive powered X-ray laser —..— weapons would damage targets by means the depth to which the beam radiation will penetrate before sur- of ablative shock. face vaporization begins. Longer pulses can produce a much greater impulse coupling. For example, an impulse coupling of 20 dyne-seconds per joule has been measured in experiments using infrared lasers [P. Bournot, et al., “Mesure de la Pres- ——— 51 sion Induite sur une Cible Metallique par une Laser C02 Im- Provided the square of this angle is greater than twice the pulsionnel, ” Journal de Physique, Tome 41, Suppl. au No. 11, cross-sectional area of the fiber divided by the square of its Colloque C9, Novembre 1980, pp. 81-86]. length. For example, a thin, one meter long XRL operating at ‘“Successful operation of an X-ray laser was claimed by a a wavelength of 20 nanometers would produce a beam with a Lawrence Livermore National Laboratories group headed by divergence angle of 100 microradians. This divergence angle Dennis Matthews at the meeting of the Division of Plasma is large compared to those achievable by lasers operating at Physics of the American Physical Society in Boston on October longer wavelengths at which mirrors can be used, and only a 29, 1984. Their laser operated at two wavelengths near 20 small fraction of the energy in a beam diverging at such an an- nanometers. The design of the laser is described by D.L. Mat- gle would would be intercepted by a satellite-sized target, at a thews, et al., in “ Demonstration of a Soft X-Ray Amplifier, ” range of thousands of kilometers. X-rays cannot be focussed Physical Review Letters, 54:110-113, 1985. More recently, the using conventional lenses and mirrors, but they can be focussed U.S. Department of Energy has stated that the nation’s nuclear- using diffraction gratings and other special optical elements weapons laboratories conducted an underground test of a nu- [R. W. Waynant and R.C. Elton, Proceedings of the IEEE, vol. clear explosive powered X-ray laser at the Nevada Test Site 64, No. 7, July 1976, pp. 1059-1092]. Such techniques may be laser and achieved lasing [see note 52, infra]. useful for generating X-ray laser beams of very high brightness. 71

6. Lasing by a nuclear explosive powered X- iodine lasers). Non-laser sources of singlepulse ray laser has been demonstrated in an un- directional radiation may also be useful as derground nuclear test at the Nevada weapons. Test Site.52 Neutral Particle Beam Weapons Weapons powered by nuclear explosions would have several disadvantages compared to Powerful particle accelerators similar to nonnuclear weapons: nuclear explosives are those used for scientific research, isotope pro- banned from orbit by the Outer Space Treaty 53, duction, and fusion power applications could they would require elaborate, costly, and be used as particle-beam weapons to attack time-consuming command and control arrange- satellites. Because electrically charged parti- ments under present U.S. policy, they would cles would travel along spiraling paths within be useful only at the nuclear level of conflict the Earth’s magnetic field, electrically neutral or would signal escalation to that level, and particles such as atoms of hydrogen, deu- they might disrupt radio propagation and dam- terium, tritium, or heavier elements would be age allied and neutral satellites when used, de- used by such weapons. Because such atoms pending on burst times, locations, and details would become ionized and hence charged if of weapon design. For these reasons there is they passed through matter as dense as the also interest in developing expendable, single- upper atmosphere, such weapons must be pulse non-nuclear laser weapons, if these should based in space and are useful only against tar- prove feasible and economical. Such lasers gets in space, although relatively small weap- might operate at short X-ray and gamma-ray ons of this type could be kept on the ground wavelengths 54 or at longer wavelengths (e.g., ready for launch into orbit and, after some on- orbit testing and calibration, for use. ‘*On January 14, 1983, in the first official public discussion of U.S. research on nuclear explosive pumped X-ray lasers, the A neutral particle beam (NPB) weapon Presidential Science Advisor, Dr. George Keyworth, suggested might consist of a negative ion source, a par- that such lasers might eventually be of great military significance, and he called the “bomb-pumped X-ray laser’ program ticle accelerator, beam focusing and pointing “one of the most important programs that may seriously in- magnets, and a “stripping” device-e. g., a gas fluence the nation’s defense posture in the next decades. ” ce1156—which strips the negative ions of their [Quoted by William J. Broad, in “Reagan’s ‘Star Wars’ Bid: Many Ideas Converging, ” New York Times, Mar. 4, 1985, p. extra electrons, thereby neutralizing them, as Al ff.]. Subsequently, Major General William W. Hoover, well as a power source and other ancillary USAF (Ret.), Assistant Secretary of Energy for Defense Pro- s8 grams, elaborated on the U.S. nuclear directed-energy research, equipment, as shown in figure 4-11. These saying that the nation’s nuclear-weapons laboratories conducted components could resemble those presently in an underground test at the Nevada Test Site of an X-ray laser use for other purposes and need not be much and achieved lasing. More recently, the Department of Energy larger to provide a modest ASAT capability. has released the other statements quoted here. 53Some have, however, questioned this interpretation, argu- For example, the hydrogen atoms produced by ing that the intent of the Outer Space Treaty was to ban weap- an accelerator at the Los Alamos Meson ons of mass destruction from orbit, not ASAT or BMD weap- Physics Facility (LAMPF) have energies of ons which would cause minor collateral damage, if any. “One concept for a short-wavelength X-ray laser envisions 800 million electron volts” (MeV) and could using a very brief and intense laser pulse to stimulate coherent, collective radioactive decay of nuclei which have been ener- 6’T.D. Hayward, et al., Negative Ion Beam Processes, Los gized by exposure to neutrons in a reactor [C.B. Collins, et al., Alamos National Laboratory, report UC-34C, January 1976, “The Coherent and Incoherent Pumping of a Gamrn a Ray La- UNCLASSIFIED; J. H. Fink, “Photodetachment Tech.nolo~,” ser with Intense Optical Radiation, Journal of Apph”ed Physics, American Institute of Physics, Conference Pmceedm“ gs No. 111, vol. 53, No. 7, July 1982, pp. 4645-4651]. Recent experimental pp. 547-560, 1984; V. Vanek, et al., “Technology for a Laser results [B. D. DePaola and C.B. Collins, ;’Tunability of Radia- Resonator for the Photodetachment Neutralizer,’ American In- tion Generated at Wavelengths Below 1 A by Anti-Stokes Scat- stitute of Physics, Conference Proceedings No. 111, pp. 568- tering from Nuclear Levels, ” Journal of the Optical Society of 584, 1984. America B, vol. 1 December 1984, pp. 812-817,; C.B. Collins “K. Boyer, ‘iDirected-Energy Beam Weapons, ” l?roceeo!ings and B.D. Paoli, “Observation of Coherent Multiphoton Proc- of the Society of Photo-Optical knhmentation Engineers, Vol- esses in Nuclear States, ” Optics Letters, vol. 10, January 1985, ume 474, 1984, pp. 79-86. pp. 25-27] have verified that some of the problems of develop- “The electron volt (eV) is a unit of energy; about 6.25 quin- ing such a laser can be solved. However, it is not yet known tillion electron volts equals one joule, the Systeme Intemation- whether nuclei suitable for use in such a laser exist. ale unit of energy. 72

Table 4-3.—A Comparison of Laser Weapons

Space-based laser (repetitive pulse Ground-based Space-based laser or continuous Ground-based laser and space- (single-pulse) wave) laser based reflectors 73 penetrate aluminum shielding 1 meter thick. the other hand, only 1.6 tons would be required The hydrogen atom beam produced by this ac- to damage such circuits at a range of 1,000 celerator has a current of 1 milliampere; irradi- kilometers, and perhaps as little as a kilogram ation of an unhardened satellite at a range of would suffice to upset or damage integrated 40,000 kilometers for several minutes by a circuits of existing hardness levels at a range beam of this current and particle energy could of 1,000 kilometers. upset the functioning of its electronic circuits. Although it may prove possible to harden A turboalternator-powered NPB weapon high-density electronics to withstand 10 kilo- might require about 25 tons of liquid hydro- grays without suffering permanent damage, gen, liquid oxygen, tankage, and other “over- it is unrealistic to expect that all satellites will head, ”68 to deliver an absorbed dose of 10 be hardened to that extent; transient upset of kilograyssg through shielding at a range of electronics, possibly causing memory loss in 40,000 kilometers, regardless of the thickness computers, could occur at doses several orders of the shielding, provided that maximum of magnitude lower. Hence a neutral particle shield thickness is known or assumed in ad- beam weapon could attack not only satellites, vance and that the weapon is designed to pene- but decoys for satellites presumed subject to trate a shield of such thickness.BO An absorbed upset, using very little fuel and overhead— radiation dose of about 10 kilograys would per- e.g., 250 kilograms to deliver a dose of 10 manently damage most radiation-resistant grays at a range of 40,000 kilometers (the dis- high-density silicon integrated circuits. Many tance from low orbit to geosynchronous orbit). existing and planned spacecraft use, or will use, According to some estimates, a NPB weap- high-density integrated circuitry with a radia- on with sufficient fuel to operate for 1,000 section hardness three or four orders of magnitude l onds must weigh about 4 tons per megawatt 1ower.’ Ten times this mass–250 tons–would B3 of beam power The U.S. Space Shuttle, or its be required to damage circuits hardened to B2 expected Soviet counterpart, could deploy into withstand 100 kilograys, at this range. On low orbit a NPB weapon weighing as much as ‘*Such as fiel for propulsion of the extra weapon fuel, oxidizer, 30 tons [see figure 4-12] .64 A heavier weapon coolant, and tankage. could be launched into low orbit by the antic- 59A gray (Gy) is the Systeme Intemationale unit for absorbed ipated Soviet heavy-lift launch vehicle, which energy dose. One gray is one joule per kilogram, or 100 rads. One kilogray is a tenth of a megarad. is expected to carry payloads as large as 150 ‘“A hydrogen atom having a kinetic energy of 50 MeV could tons. Even heavier weapons could be assem- penetrate about a centimeter of aluminum shielding. If the bled in space by the United States or the So- thickness of the shield were increased, particle energy, and hence also weapon size, would have to be increased in order to pene- viet Union. trate the shielding, but the amount of beam energy and weapon fuel required need not increase. The reason for this is that as A neutral-particle beam could be made to di- particle energy is increasti, beam divergence can be decreased, verge at a small angle and would therefore and the same number of particles per unit area per second could be delivered (over a smaller area) with a lower total beam current (particles per second). Hence a high-energy, low-current weapon could penetrate thicker shielding and deliver the same con circuits. For example, the Sandia National Laboratories of radiation dose in the same time over a smaller cross-sectional the U.S. Department of Energy has fabricated a pin-for-pin area of a target than could a lower-energy, higher-current equivalent of the Intel Corporation’s 8085 8-bit microproces- weapon of equal beam power ( which equals particle energy sor chip which can function after absorbing a 100-kilogray dose times beam current). of garnm a radiation and can withstand singleevent upsets alDo9e9 of 100 ways would probably upset electronic circuits caused by 140 MeV particles. Sandia plans to fabricate a 32- on most satellites. It would be possible to shield such circuits, bit silicon microprocessor chip hardened to withstand 10 but the shield mass required would increase more rapidly than kilograys. would the mass of a weapon which could penetrate it. On the “E. g., see K. Boyer, “Directed-Energy Beam Weapons, ” other hand, it is possible to fabricate integrated circuits capa- Proceedings of the Society of Photo-Optical Instrumentation Engi- ble of withstanding radiation doses as high as 100 kilograys. neers, Volume 474, 1984, pp. 79-86. 6ZLow-density g~lium arsenide circuits which cm withstand “U.S. Department of Defense, Soviet IUfi”tary Power, 3d cd., 100 kilograys have been fabricated, as have higher-density sili- 1984, p. 44. 74

Figure 4-12.—Artist’s Conception of the Space Shuttle A neutral particle beam weapon could ac- Deploying a Neutral Particle Beam Weapon quire (i.e., detect) a target using a passive long- wavelength infrared (LWIR) sensor; it could then track the target using an active optical tracker (LIDAR) and use this tracking information to determine the angle at which its beam must be pointed at the target. However, this approach only guarantees that the optical tracker is pointed at the target and cannot directly sense whether the beam itself is pointed at the target. That is, open-loop pointing must be used for neutral particle beams, while more accurate closed-loop pointing can be used by lasers. Determining whether open- loop pointing of a neutral particle beam can be done with an accuracy comparable to beam divergence angles may require testing of neutral particle beam generators in space against instrumented targets. Aside from these difficulties of pointing and kill assessment, neutral particle beam weapons are among the most promising near-term options for nonnuclear ASAT weapons because of the maturity and demonstrated per- SOURCE U S. Department of Energy, Los Alamos National Laboratory formance of their component technologies and the relative diseconomy of hardening targets against neutral particle beams. However, neu- have a relatively small diameter even at great tral particle beam weapons, like other space- distances-e. g., 40 meters diameter at a range based sequential-fire weapons, would be sub- of 40,000 kilometers. A beam this small must ject to attack by single-shot weapons against be pointed at a target with an accuracy of which shoot-back and other reactive counter- about 1 microradian, and this presents a more measures would be ineffective. They would difficult problem in the case of a neutral par- have little operational effectiveness unless ticle beam than in the case of a continuous- their survivability can be assured. wave or repetitively pulsed laser. The tracking and pointing systems of such lasers can It appears, then, that if accurate open-loop quickly sense reflected beam energy from tar- beam pointing can be demonstrated, it will be gets and thereby determine whether their feasible to build neutral particle beam weap- beams are actually on target. However, a tar- ons which, if deployed in low orbit, would pose get would emit very little radiation when ir- a serious threat to satellites in low and high radiated by a neutral particle beam. Sensors orbit. Against this threat only shoot-back within several hundred kilometers of a target would be economical for protecting low satel- might be able, during NPB irradiation, to de- lites, while hardening and deception might pro tect enough x-radiation or garoma or other ra- tect high-altitude satellites at low relative cost. diation from the target to determine that the At close range (1,000 kilometers), neutral par- target had been hit, but it could not detect ticle beam weapons could damage satellite such radiation fast enough to correct beam electronics of current hardness levels and up- pointing errors based on its presence or absence. set harder future satellite electronics using 75 relatively little fuel and tankage (etc. )—prob- nous orbit, from low orbit, using little mass ably about 1 kilogram per shot. The cost per per shot (e.g., 25 kilograms for a dose of 10 shot at a satellite hardened to this level, or at grays); however, hardening high-density elec- a decoy simulating such a satellite, would be tronics on such satellites to 10 kilograys and very cheap relative to the cost per satellite or using upset-tolerant circuit design could in- decoy. Hardening satellite electronics would crease the mass requirement for damage to increase the cost per shot, although probably perhaps 25 tons per shot and would increase not to the cost of the smallest satellites or pre- required irradiation time enough to permit use cision decoys: damaging high-density elec- of reactive passive countermeasures such as tronics hardened to the greatest extent now generation of smoke or deployment of reaction foreseeable would require about 160 kilograms decoys. Shielding satellites-as distinct from per shot. hardening their electronics-would be economically unfavorable against larger weapons: a Such weapons, if encountered, could place disproportionately small increase in weapon low-altitude satellites at risk at relatively low mass, with no increase in mass per shot, could cost. They could also upset or damage un- compensate for an increase in shield mass. hardened electronics on satellites in synchro-

POSSIBLE U.S. RESPONSES TO SOVIET ASAT CAPABILITIES How might the United States respond to in- were less expensive and less vulnerable than creasingly threatening Soviet A SAT capabil- other means to these ends, dependence on sat- ities? Several options are available. For exam- ellites was not risky. In the future, satellites ple, an increase in U.S. ASAT capabilities may become so vulnerable that use, if possi- might—but would not necessarily-be an a- ble, of more expensive but less vulnerable ppropriate response. Although useful for at- means of performing functions now performed tacking Soviet MILSATS, they might be un- by space systems may be required for ade- able to protect U.S. MILSATS. Other possible quate security. responses include reduction of dependence on Most functions now performed by space sys- military satellites, augmenting U.S. combat tems could be performed by alternative terres- forces (to offset possible loss of force enhance- trial systems, although terrestrial systems ment as a result of an ASAT attack), use of providing comparable performance of some passive or active countermeasures for defense functions would be unaffordable or politically or retaliation, and arms control efforts or other unacceptable. Missile launch detection and diplomatic initiatives intended to constrain space surveillance could be performed by air- foreign ASAT capabilities or reduce incentives borne optical sensors; navigation by advanced to use them. inertial navigation systems which can recog- Reduction of Dependence on nize local gravity gradient patterns, nuclear detonation detection by ground-based over- Military satellites thehorizon electromagnetic pulse (OTH EMP) The United States routinely uses satellites sensors, and radio communications relaying to support its forces deployed worldwide to by MF ground-wave, HF ground-wave and reinforce allies, protect sea lines of communi- sky-wave, VHF meteor-burst, UHF tropo- cation, and pursue other national interests. spheric scatter, and UHF/SHF/EHF and light- Routine use of satellites for such purposes has wave airborne repeaters. Reconnaissance engendered a considerable degree of depen- could be performed in wartime by aircraft dence on them. In the past, when satellites overflight at great expense and risk. 76 — —

On the other hand, the kind of information Figure 4-13.—Cost Comparison: Satellite and RPV R-clays for Single-Channel UHF Tactical Theater presently collected by satellites in peacetime - to monitor compliance with arms control Communications agreements cannot be obtained by other means which are acceptable in peacetime. Un- authorized aircraft overflight, for example, would be unacceptable. However, arms control treaties—like other treaties except those defining “laws of war’ ’-are suspended during war between parties, so a survivable space- based means of performing this function is not required. Although alternative terrestrial systems for performing some functions may be infeasible or very expensive, alternative terrestrial systems for performing other functions may be only slightly more expensive than space systems. For example, providing intra-theater single-channel UHF communications to mobile ground elements in the 1980s by means of satellite communications transponders would be less expensive than use of remotely Satellite Satellite with RPV piloted vehicles (aircraft) carrying transpond- null-stewing antenna ers, but only slightly so [see figure 4-13]; a slight increase in satellite vulnerability would make the costs favor use of RPVS. Whether support, larger future forces, although im- alternative terrestrial systems are worth their paired in effectiveness, would fight as well as cost depends on the function to be performed or better than would current forces using sat- and is a matter of judgment deserving peri- ellite support. The force augmentation re- odic reconsideration. quired by this criterion might, under some circumstances, be modest. Force Augmentation As satellites have been acquired and inte- Passive Countermeasures grated into military systems, they have pre- “Passive” countermeasures against ASAT sumably increased the effectiveness of force capabilities include hiding, deception, maneu- elements which would engage in direct com- ver, hardening, electronic countermeasures bat, so that each such force element can now and electro-optical countermeasures, and fight as well as, say, one and a half could with- proliferation, as well as combinations of these out MILSAT support. Having become depen- measures [see table 4-4]. Some of these coun- dent on satellite support, if suddenly deprived termeasures—e.g., hardening-are truly pas- of that support the effectiveness of a force ele- sive, requiring no satellite activity for their ef- ment would be reduced, not just to that of a fectiveness, while others—e.g., evasion—re- force element unaccustomed to such support quire satellite activity–and hence attack but probably more so because of the disorga- warning-and are not truly passive, although nizing effect of losing sources of information they are nondestructive. it had come to count on. Nevertheless, it is possible, in principle, to augment current forces For expository purposes it is convenient to so that in the event of sudden loss of MILSAT discuss each type of countermeasure in isola- 77

Table 4-4.— Passive Countermeasures usedGb In general, passive optical sensors on Against ASAT Attacks satellites in low Earth orbit maybe able to de Hiding tect satellites as small as a meter in diameter e.g., satellite miniaturization and orbit selection at altitudes between a few hundred kilometers Deception and geosynchronous altitude. e.g., deploying lightweight decoys Maneuver Passive LWIR and visible light sensors can e.g., evasion Hardening work better in combination than either can e.g., use of shielding alone. For example, painting a satellite black Electronic countermeasures and electro-optical would prevent it from reflecting sunlight and countermeasures e.g., use of shorter wavelengths and more highly thereby make it invisible to passive visible directional antennas light sensors. However, painting a satellite Proliferate ion black would cause it to absorb more solar ra- e.g., of on-orbit-— spare satellites —. — diation and become hotter. In thermal equilibrium it would emit more LWIR radiation, tion from the others in the context of a one- making it detectable at greater range by a pas- against-one ASAT attack, as will be done here. sive LWIR sensor [see box entitled “Long- However, it is anticipated that such counter- wave Infrared (LWIR) Space Surveillance measures, if used, might be used in combina- Sensors”]. tion in the context of a many-against-many Operating a satellite at very low altitude can (i.e., force-against-force) space battle. It is in make it difficult to detect using space-based such a context that the potential effectiveness infrared sensors which must view it against of a countermeasure should be assessed. How- the radiant Earth or Earth limb background. ever, the number and complexity of possible More satellites would be required to perform contexts precludes any attempt at assessment a given function at lower altitude, and user of countermeasure effectiveness from being ex- equipment might also have to be more com- haustive or conclusive. plex and expensive.

Hiding Deception “Hiding” measures are measures taken to The use of decoys to induce an enemy to evade detection by surveillance systems. In waste firepower on false targets-or to with- some sense the effective use of hiding, if fea- hold fire for fear of doing so–can always be sible, would be most desirable, because it made effective, if the decoys are sufficiently would eliminate the need for other counter- realistic, i.e., “credible” to enemy space sur- measures, all of which require increases in on- veillance systems. A decoy can always be orbit mass in the form of decoys for deception, made credib~e at a cost less than or equal to fuel for evasion, shielding for hardening, or that of the satellite it mimics, because a spare spares for proliferation. satellite could be used as a decoy, and it would Different hiding measures are required be preferable to do so rather than spend as against different types of surveillance sensors. much on a nonfunctional decoy. The critical Space surveillance systems may be of two question is whether a decoy can be made credi- types: active and passive. Active sensors ir- ble at a much lower cost than that of the satel- radiate a target with electromagnetic radiation in order to “see” it, while passive sensors look ’51n most cases passive sensors are preferable to active sensors because they do not require a high-power radiation source for electromagnetic radiation emitted by the for irradiating targets, they are themselves consequently more target or reflected by the target from natural difficult to detect, and their effective range can be increased sources, e.g., the Sun. At optical wavelengths more economically, because a twofold increase in range to a target decreases the irradiance received by a passive sensor only (infrared, visible, and ultraviolet), both active fourfold as compared to sixteenfold in the case of an active sensors (LIDAR) and passive sensors may be sensor. 78 .—— —

Long-Wavelength Infrared (LWIR) Space Surveillance Sensors The following discussion describes the phys- make the satellite less visible to passive LWIR ical basis for the estimated detection capabil- sensors. ities of passive LWIR sensors and for the in- effectiveness of hiding measures against them. Passive optical sensors may be designed to detect targets within view above the horizon Every object emits electromagnetic radiation (ATH) or below the horizon (BTH). BTH detec- as a result of thermal processes; the amount of tion is more difficult than ATH detection, and power emitted by an object increasesin propor- the image processing required by BTH sensors tion to its surface area and would increase six- is more complicated than that required by ATH teanfold if its temperature were doubled. A sat- sensors. ATH sensors are therefore preferred ellite at a typical operating temperature-about for passive optical space-based surveillance 300° K—emits most of its thermal radiation at systems. a wavelength of about 10 microns [10 millionths of a meter], which is in the LWIR portion of the Space-based LWIR ATH sensors could not electromagnetic spectrum. The wavelength at eady detect satellites which orbit at altitudes which thermal radiation is most intense varies so low that they are actually within the upper in inverse proportion to the temperature of its atmosphere. Satellites at such low altitudes source; thus the surface of the Sun-which has would be in the “Earth limb” as viewed by a a temperature of about 6,000° K-emits ther- space-based LWIR ATH sensor, which would mal radiation (sunlight) which is most intense have to view the satellite just above the hori- at a wavelength of 0.5 microns, a wavelength zon through a thick layer of air which would ab- in the visible portion of the electromagnetic sorb much LWIR radiation and which would spectrum Passive optical sensors which can de- emit, reflect, and scatter LWIR background ra- tact LWIR radiation can detect the thermal radiation against which the satellite would have diation emitted by satellites, while those sensi- to be viewed. Satellites at such low altitudes tive to visible radiation are best suited for would experience considerable atmospheric detecting sunlight reflected by satellites. Visi- drag and would slow down and reenter the ble light sensors are preferred for ground-based atmosphere sooner unless they amid maneuver space surveillance systems because LWIR ther- and carried enough fuel to compensate for the mal radiation is absorbed strongly by the lower drag. Operating in such an altitude regime to atmosphere, although LWIR telescopes have evade detection by space-based LWIR ATH been operated on mountain peaks and on sensors would also impose operational penalties aircraft. in some cases. For example, surveillance satellites could not “see” as far from lower altitudes. Passive LWIR and visible light sensors can work better in combination than either can Required image processing sophistication alone. For example, painting a satellite black would be more difficult for general surveillance would prevent it from reflecting sunlight and than for warning of interception of the satelllite thereby make it invisible to passive visible light carrying the sensor. This is because the spot of sensors. However, painting a satellite black focused radiation from an interceptor approach would cause it to absorb more solar radiation ing a satellite-borne sensor “staring” at the and become hotter.x In thermal equilibrium it celestial background in the direction of the ap- would emit more LWIR radiation, making it de- proaching interceptor would not move on the tectable at greater range by a passive LWIR sensor’s focal plane, and a single detector ele- sensor. Conversely, making the satellite surface ment of the sensor could accumulate thermal ra- highly reflective would reduce its absorptivity diation from the interceptor until sufficient and hence also its emissivity, which equals the energy for detection has been accumulated. By absorptivity at each wavelength; this would contrast, the spot of focused radiation from an interceptor traveling in some arbitrary direction would move on the sensor’s focal plane, limit- ‘s. Stetnberg and V.P. 141am %@,elwesyatam” @h. 17), R.E. Mtil{ed}, 8wmE z@neer@Hantilnmk (New York: McGraw- ing the time available to a detector element for w 1965). accumulating image energy. 79

If the target’s angular position and velocity detect a black-painted satellite 1.5 meters in di- is approximately known by other means, the ameter at a range of 35,000 kilometers using a number of photons received by each detector l millisecond integration (energy accumulation) element over which the target’s image is ex- time. In one millisecond the image of a small pected to move could be added in order to ac- satellite at geosynchronous altitude would cumulate image photons and average out the move across the face of a detector element the noise photons. However, if the target’s angu- size of the telescope’s “spot size,” if the teb lar position and velocity is not known ac- scope were on a satellite at 1,000 kilometers al- curately by other means, the number of possi titude and “Stared” Continuosly toward the ze- ble averages which must be calculated in this nith. It would be feasible and affordable, but way to detect the target reliably increases very costly (several billion dollars), to deploy a con- ‘ rapidly with increasing uncertainty about tar- stellation of satdlites of this performance which get position and velocity, and the required mass stare continuously in all directions above the of image-processing hardware required will in- horizon. Even smaller objects could be detected crease correspondingly. at greater range using a larger primary mirror, or-less economically in the limit-more image- A low-orbit LWIR space surveillance satellite processing hardware. ‘ with a 1 meter nonemissive primary mirror and a focal plane detector army cooled to 77° K could

lite it mimics, as well as cheaper than an enemy’s Alternatively, inexpensive “traffic” decoys cost to identify it (e.g., by dispatching a coor- could be made to simulate only those features bital interceptor to observe it at close range) of a capital satellite which might be measura- or to attack it in a manner which would negate ble cheaply, quickly, and remotely. Reflective the satellite it simulates. This critical question balloons or clouds of smoke and chaff could remains unanswered. be used as “reaction decoy s,” i.e., they could be deployed in reaction to warning of an im- Before any of these costs can be estimated, pending attack.” Even if such decoys could the designs of decoys and enemy surveillance deceive an enemy for only a limited period of and weapon systems must be specified. Many time, they could be effective in some situa- design choices are available. For example, for tions. However, reaction decoys offer no pro- the same amount of money, a few highly re- tection against single-shot ASAT weapons alistic decoys (called “precision decoys” or (e.g., “space mines”) which can destroy satel- “replica decoys”) could be built, or a much lites almost instantly before reaction decoys larger number of less realistic but less expen- can be dispensed. Ingeniously designed light- sive decoys could be built. A “precision” de- weight decoys might be both inexpensive and coy designed to simulate an on-line satellite highly credible to passive remote sensors; would probably have to simulate attitude con- whether they will be is uncertain. trol, stationkeeping, signal transmission, power generation and heat dissipation, and ———...— other observable functions and properties. The ‘aFor example, a satellite under attack by a pop-up infrared- subsystems required to do this would be rela- homing interceptor could dispense several lightweight decoys which resemble it, from a distance, in infrared brightness tem- tively expensive. If such decoys could not be perature and color temperature. If the interceptor cannot dis- distinguished from actual satellites, all such tinguish such decoys from the capital satellite until it has flown decoys would have to be attacked in a man- past, then the decoys would be adequately “credibIe.” Because satellite mass cannot be measured both quickly and inexpen- ner which would damage the satellites they sively, cheap, lightweight decoys could be effective as reaction simulate. decoys. 80

Even if lightweight decoys cannot be recog- cost are sometimes derived from estimates of nized as such after prolonged remote passive satellite subsystem mass and complexity. observation, it might be possible to recognize However, analysis of historical cost data re- them using directed-energy devices.87 How- veals considerable variation in satellite cost ever, use of directed-energy devices in such a for satellites of comparable small mass.og manner might be provocative in peacetime and Deception is more advantageous when used possibly more expensive than the cost of light- in combination with other passive measures such weight decoys. as hardening and proliferation. For example, If lightweight decoys cannot be distin- dormant spare satellites can be hardened and guished from actual satellites, all such decoys made to resemble cheaper decoys. would have to be attacked, although not nec- These considerations lead OTA to conclude essarily in a manner which would damage the that the question of whether decoys can be made satellites they simulate, because the cost of at- credible at a much lower cost than that of the tacking and observably damaging a light- satellites they mimic or than an enemy’s cost weight decoy with some types of A SAT weap- to identify them or to attack them in a manner ons could be comparable to, or smaller than, which would negate the satellites they simulate the cost of attacking a decoy in a manner remains unanswered, and that answering this which would damage a satellite which it simu- question is essential in any attempt to assess lates. For example, ground-based lasers might prospects for making future satellites ade- be able to attack lightweight decoys inexpen- quately survivable. An affirmative answer will sively. Neutral-particle beam weapons could probably require detailed designs for decoys also be used to attack decoys at long range, which are inexpensive and lightweight as well as could singlepulse lasers, although less eco- as credible to possible future Soviet surveil- nomically. lance systems. The large number of possible designs for decoys and enemy surveillance and weapon sys- Maneuver tems renders assessment of the cost-exchange W Satellites may maneuver in order to compli- ratios of future systems infeasible at this time. cate enemy surveillance and targeting and to Furthermore, even if the decoy design were speci- evade enemy fire. Satellites which do not ma- fied, it would be difficult to estimate decoy costs neuver are nevertheless unavoidably mobile, accurately. Rough preliminary estimates of although in fixed orbits. Because of this prop- satellite cost and of uncertainty in satellite erty, the relation of maneuver to attrition is different in space than on land or at sea, and 6TRefernng t. the possibility of active discrimination of de- proximity in terms of orbital elements (e.g., coys from ballistic missile reentry vehicles, Dr. Gerold Yonas, apogee, perigee, inclination, etc.) has as much Chief Scientist of the Strategic Defense Initiative Organization, tactical significance as does momentary prox- has written that “directed energy, even in a very early period, imity in space. A maneuver, loosely speaking, could be used in an interactive mode to assist in midcourse discrimination IGerold Yonas, “Strategic Defense Initiative: The is an action which changes a satellite’s Kep- Politics and Science of Weapons in Space,” Physics Today, June lerian orbital elements. Pursuit of another sat- 1985, pp. 24-32; cf. remarks attributed to Dr. Yonas in E.J. ellite and evasion of an interceptor are exam- Lemer, “Star Wars: Part II–Survivability and Stability, ” Aerospace America, vol. 23, No, 9, Sept. 1985, pp. 80-84]. ples of maneuvers. s8The relevat Cost-exchmge ratio is the minimax c05t-exchange ratio, i.e., the ratio of decoy costs to Soviet ASAT sen- In order to continuously evade an intercep- sor and weapon costs which would be incurred if decoys were tor—whether pop-up or coorbital-a satellite designed to minhniz e the maximum cost-exchange ratio which must have an acceleration capability and a ve the U.S.S.R. could subsequently force on the United States by judicious choice of ASAT sensor and weapon designs. The cost- locity change (“delta-V”) capability about as exchange ratio of a specific future system is of questionable relevance, unless the system can be shown to have a cost- ‘There has been less variation in cost per kilogram among exchange ratio close to the minimax cost-exchange ratio. satellites of large mass. 81 great as those of the interceptor, but some- from 0.1 g meteoroids impacting at 70 kilom- what more or less, depending on initial posi- eters per second. ’l Such shields could be all- tions and velocities.’” Acceleration and delta- aspect shields which completely surround a V can be maximized by minimizing the mis- satellite, or they could be “shadow shields” sion payload, so that a large fraction of the deployed between the defended satellite and spacecraft initial mass is contributed by its a weapon which poses a threat to it. Shadow engines (for acceleration) and fuel (for delta- shields could be deployed on a boom or they V). Because an interceptor’s payload can be could be independent, ‘‘free-flying” satellites. quite small-perhaps comparable to that of a Shadow shields could be lighter than all- shoulder-fired anti-tank missile—an intercep- aspect shields, but a separate shadow shield tor might have acceleration and delta-V capa- might be required for each known or suspected bilities which would be much more costly to threatening weapon. All-aspect shields would provide to satellites with large mission pay- be superior to shadow shields in that they loads such as long-range directed-energy weap- could defend a satellite from multiple sequen- ons. If so, it would be difficult for such satel- tial or simultaneous attack from any direction lites to evade small but sophisticated or all directions and from covert weapons and interceptors. they would require no power or warning infor- Hardening mation for their operation. For each type of ASAT weapon, there exist Massive shields could also protect satellites hardening techniques which can reduce the from laser radiation and from neutral particle range at which the weapon would be effective. beams. Relatively little shield mass would be For example, satellites may be hardened to required to protect a satellite from beam of withstand the effects of ordinary, isotropic low-energy particles (i.e., those having ener- nuclear weapons by avoiding reliance on pho- gies of less than 50 to 100 MeV), but the shield tovoltaic cells—which are vulnerable to weap- mass required would increase sharply if par- on X-rays—for power, by using massive shield- ticles of higher energy, produced by larger ing to block gamma radiation, and by using NPB weapons, were used. Faraday shielding, magnetic shielding, and Semiconductor microelectronic circuits in- fault-tolerant electronic design to reduce vul- side satellites could also be made more resis- nerability to system-generated electromag- tant to ionizing radiation such as would be netic pulse. Of course, such practices cannot produced by a neutral particle beam. For ex- protect a satellite from a nearby nuclear example, the Sandia National Laboratories of the plosion, but they can force an attacker to ex- U.S. Department of Energy have fabricated pend at least one nuclear warhead per satel- a pin-for-pin equivalent of the Intel Corp. ’s lite and credible decoy to destroy them with 8085 8-bit microprocessor chip which can func- confidence. tion after absorbing a 100-kilogray dose of Shielding, or armor, of different types can gamma radiation and can withstand single- offer protection against some types of projec- event upsets caused by particles with energies tiles, pulsed or continuous lasers, and neutral as great as 140 MeV. particle beams. Different types of shields The use of asteroidal materials such as would be required for protection against dif- nickel for large, massive, all-aspect shields has ferent types of ASAT threats. For example, been proposed. Possible advances in space shields could be used against projectiles, mining, manufacturing, and transportation— pulsed lasers, and neutral particle beams, re- which would require large investments-might spectively. For example, NASA developed shields to protect a Halley’s Comet probe craft ‘IJ. P.D. Wilkinson, “A Penetration Criterion for DoubIe- Walled Structures Subject to Meteoroid Impact, ” AIAA Jour- ‘“G. M. Anderson, op. cit. nal, vol. 7, No. 10, October 1969, pp. 1937-1943. 82

someday make use of asteroidal material for number of them would depend on enemy such purposes cheaper than use of terrestrial ASAT capabilities. The extra satellites could material.72 be placed in orbit or else kept on Earth to be launched into orbit after an ASAT attack to These considerations suggest that, in gen- replenish those satellites destroyed by the eral, shielding against weapons of relatively attack. low capability is feasible and in many cases may be less expensive than the weapons Unless on-orbit spare satellites are also de- against which it can offer protection. However, ployed, replenishment could not be relied on as weapons are made larger, more capable, and to maintain uninterrupted performance of sat- more numerous, the cost of protection against ellite function, which is essential for such ap- such weapons generally increases more rapidly plications as early warning of missile attack than the cost of the weapons and and begins and other strategic command and control func- to exceed the cost of the weapons at some tions. If it is cost-effective for an enemy to ne- point. gate an operational satellite, it would probably be cost-effective for the enemy to negate Electronic Countermeasures and replacements, if enemy ASAT capability sur- Electro-Optical Countermeasures vives. It would also be cost-effective for an Passive electronic and electro-optical coun- enemy to maintain enough ASAT weapons or termeasures can provide protection-analo- fuel to avoid exhaustion of ASAT capability gous to “hardening”—against nondestructive before replenished satellites can be negated. ASAT measures. For example, communica- Hence replenishment appears unattractive as tion links can be made increasingly resistant a countermeasure unless enemy ASAT capa- to jamming by using more transmitter power bility can be destroyed before replenishment (which ultimately becomes uneconomical) or is attempted, and unless the satellites to be signal bandwidth (which is limited except at replaced need not function without inter- extremely high radio frequencies and optical ruption. frequencies), or–in some applications-by using larger antennas or shorter wavelengths Proliferation-On-orbit Spares for greater directionality of transmission and Spare satellites could also be pre-deployed reception, or by transmitting at a lower data in orbit, where they could remain dormant un- rate. Command encryption can prevent spoof- til needed or else be used routinely to provide ing, and use of spread-spectrum modulation redundant capability in peacetime. Dormant and time-division multiplexing techniques can satellites would need to listen for radio com- provide significant resistance against uplink mands to activate and might need to report and downlink jamming and against downlink their status occasionally but in general would exploitation (e.g., by anti-radiation missiles). require little power generation, cooling, attitude control, or exposure of antennas or other Proliferation-Replenishment sensors while dormant and could be made Another countermeasure against ASAT at- harder than operational satellites. Their armor tack is proliferation of satellites, so that even could have a simple shape easily mimicked by if a large fraction of the satellites were dam- inexpensive decoys; hence proliferation of on- aged by hostile action, enough undamaged sat- orbit spares would work more effectively in ellites would remain to perform their assigned conjunction with hiding, deception, and hard- functions. The number of additional satellites ening measures. However, an enemy which can needed to assure survivability of a required negate an operating satellite might be able, by the same means, to negate an on-orbit spare once it became operational. Proliferating and 72C. Meinel, “Near-Earth Asteroids: Potential Bonanza for simulating dormant spare satellites will not Ambitious Military Space Projects, ” Defense Sa”ence 2003 +, February-March 1985, p. 40 ff. preserve the functioning of a constellation of 83

satellites if the spares can be identified and Figure 4-14.— Low-Cost Packet-Switching negated quickly and cheaply after being Communications Satellite brought “on-line.” Hence the use of on-orbit spares would be most attractive if enemy A SAT weapons could be themselves negated soon after space combat begins.

Proliferation—Modularization and Segregation Another form of proliferation is the parti- tioning of satellite subsystems into modules which can be segregated and deployed on different satellites. For example, the function of a high-capacity comsat could be performed by several small comsats which pass message “packets” to one another over radio or laser crosslinks.7s Functions such as stationkeeping might be performed by maneuverable satellite ‘‘tenders, each of which could visit one satellite after another, adjusting their positions and velocities as needed. Segregation of subsystems would require forgoing economies of scale in peacetime in order to reduce vulnerability.

Combined Passive Countermeasures Passive countermeasures work better in combination than individually. For example, use of decoys for deception would confer little protection against some (e.g., nuclear) A SAT weapons unless maneuver were used to disperse the decoys. It is therefore important The Global Low-Orbiting Message Relay Satellite (GLOMR), shown here, is designed to receive messages sent to It, store them, and relay to consider the effectiveness of “packages” of them to ground facilities. The GLOMR program of the Defense passive countermeasures against various Advanced Research Projects Agency (DAR PA) is intended to ASAT capabilities, which can also supplement demonstrate that communications satellites operating in this manner can be produced at relatively low cost. If sufficiently Inexpensive, and complement one another and which should such satellites could be deployed at lower cost than the cost of attacking them with some types of ASAT weapons, and so many could also be considered packages, or postures, be deployed that other weapons might require a long t!me to destroy Active countermeasures could, and probably most of them would, be used to complement passive coun- SOURCE U S Department of Defense termeasures unless prohibited by a comprehensive ban on possession of ASAT weapons. elude nondestructive ASAT capabilities (e.g., Hence in hypothesizing ASAT threats to be ECM and E-OCM), and inherent ASAT capa- countered by passive measures alone, it is bilities of allowed weapons (e.g., ICBMS); the appropriate to consider as threats only those latter include the existing Soviet coorbital in- capabilities which are unlikely to be banned terceptor, direct-ascent and coorbital nuclear or those which might be developed and de- interceptors, space-based or pop-up X-ray laser ployed (or retained) covertly. The former in- weapons, and possibly ground-based lasers. Of these, the nuclear weapons might be based in ‘-’The L~efense Advanced Research Projects Agency (DARPAI is investigating the feasibility of a packet-switched network of space disguised as, or aboard, a different type transponders on low-altitude satellites, or on Earth, o; satellite, the presence of which would be-ob- 84 servable but the nature of which might be im- effectiveness of shoot-back highly dependent possible to ascertain except by prolonged close on the types and numbers of ASAT and other observation or invasive sensing techniques.74 weapons deployed and on the incentives for In general, nonnuclear space-based weapons preemptive attack which ASAT weapon vul- could not be expected, with confidence, to per- nerabilities, if any, could create. Analysis of form well, unless they had been previously– the effectiveness of shoot-back is therefore and observably—tested in space. very complicated in general, although simple in certain important cases. Active Measures For example, shoot-back would be ineffective Passive countermeasures against ASAT at- against expendable, single-shot space mines em- tacks may be supplemented by active meas- ploying kinetic-energy, directed-energy, or nu- ures intended to deter ASAT attack or to de- clear destructive mechanisms. Such weapons fend satellites if deterrence should fail. Active would damage their targets almost instantly, measures can therefore be used for either if at all, and destroy themselves in the proc- defensive or retaliatory purposes. Defensive ess, leaving nothing of value to shoot back at. active measures are active countermeasures Moreover, shoot-back using sequential-fire against ASAT attacks. Retaliatory active weapons which are vulnerable to attack by ex- measures do not counter ASAT attacks but pendable, single-shot weapons would be ineffec- instead fulfill explicit or implied threats of tive, because they could be damaged by single retaliation which were intended to deter ASAT shot weapons after attacking only one target. attacks. Active measures used for either pur- However, space-based single-shot ASAT weap- pose can be either nondestructive (e.g., elec- ons would themselves be subject to preemp- tronic countermeasures and electro-optical tive attack—i.e., “shoot-first” instead of countermeasures) or destructive (e.g., shoot- “shoot-back.” If such weapons were mutually back), as shown in table 4-5. deployed in space, if each such weapon could instantly destroy several similar weapons and Defensive Countermeasures if such weapons were not salvage-fused to fire if disturbed, the resulting preemptive advan- Shoot-Back.–” Shoot-back” usually refers tage could cause a condition of “crisis insta- to counter-attacking spacebased ASAT weap- bility, ” in which each nation, desiring peace ons, but can also denote counter-attacks but fearing (perhaps mistakenly) an imminent against the ground segment of A SAT weapon attack by the other, would have reason to ini- systems (e.g., satellite control facilities). Many tiate hostilities.7s weapons capable of shoot-back would themselves be subject to shoot-back, making the However, it is conceivable that even if such incentives should induce escalation from peace “E. g., see U.S. Patent 4,320,298. or low-level conflict to war in space, the preemptive ASAT attack which would begin such a war might reduce incentives for further es- Table 4.5.—Active Measures Against ASAT Attack calation, either “vertically” (to higher levels of conflict) or horizontally (to other theaters Defensive measures: Nondestructive of conflict, e.g., Earth). For example, if the e.g., jamming United States and the U.S.S.R. continue to Destructive possess strategic offensive missile forces of shoot-back attack on ground-based ASAT command and considerable counterforce capability, and if control facilities each were to deploy a large BMD system Retaliatory measures: ASAT counterattack (retaliation in kind) 5 ‘ See M.B. Callaham and F.M. Scibilia, Proceedings of the Horizontal escalation Society of Phot~Optical Instrumentation Engineers, vol. 474, (to terrestrial theaters) ——— 1984, pp. 107-114. 85 which relied on vulnerable space-based com- weapons would not be expected to create ponents, then each nation might fear that the strong proliferation incentives: with mutual other nation (also fearing a preemptive attack) salvage-fusing each side could plausibly lose might attack these BMD components preemp- all its important space assets in such an ex- tively with some confidence that its BMD sys- change regardless of whether it had many such tem could limit damage from a retaliatory mis- weapons or only a few deployed; it would sile attack, if any. Each nation would therefore therefore have no incentive to deploy more have an incentive to attack the other’s space weapons than would be required to negate all based BMD components preemptively. How- threatening satellites except single-pulse ever, after having done so, the attacker would ASAT weapons, against which neither have no motive to launch a preemptive, dam- preemptive attack nor shoot-back would be ef- age-limiting missile attack, because it could fective. Without salvage-fusing, the side which assume that the other nation—now highly vul- failed to preempt could plausibly lose all its nerable to retaliation-would not seriously important space assets in such an exchange consider such an option. Hence, under these regardless of whether it had many such weap- assumptions, escalation instability would ex- ons or only a few deployed, and would there- ist during crises in peacetime (thus “crisis in- fore gain nothing by deploying many weapons. stability’ but not at the level of war confined Electronic Countermeasures and Electro-Optical to space. Countermeasures.–Active electronic and It might be supposed that the crisis insta- electro-optical countermeasures (jamming, bility which would accompany mutual deploy- blinding, and spoofing) could be used against ment of such weapons could be eliminated by some near-term ASAT command uplink sys- salvage-fusing them to fire if disturbed in cer- tems, KEW homing systems, and DEW acqui- tain ways (presumably indicative of an attack). sition, tracking, and pointing systems which If salvage-fusing were feasible and actually have inadequate counter-countermeasures. used (or believed to be used), there might be Attack on Ground-Based ASAT Weapons or little incentive to fire first even if an attack Support Systems. —At present there appear to were expected. However, salvage-fusing some be only two launch pads for Soviet coorbital types of weapons against some other types interceptors, both at Tyuratam, and only two may be inordinately difficult or infeasible. Soviet ground-based lasers of significant Moreover, even though an “intelligent” ASAT capability, both at Sary Shagan. Hence salvage-fusing system might be able to distin- attacking such ground-based facilities with guish among different types of disturbances, conventional or nuclear weapons could be very it could not be made completely reliable or ineffective, especially if preemptive, but would fallible in discrimination, so there would be a be viewed by some in the United States as es- risk that some natural disturbance (e.g., a me- calator with respect to attacking or defend- teoroid impact) might trigger such a weapon ing satellites using nonnuclear weapons. to fire, possibly at several similar enemy weapons, possibly triggering them to fire, etc. Sim- ilar consequences could follow an accidental Retaliatory Measures attack or a “catalytic” attack by a third party. The ability to respond to ASAT attack by Moreover, if salvage-fused spacebased weap- active measures could be maintained and pub- ons only held an enemy’s spacebased assets licized in an attempt to deter such an attack at risk, the prospect of losing such assets in in the first place. Postures and policies in- retaliation for an attack might be considered tended to enhance deterrence could act as ad- an acceptable or favorable trade by a nation juncts to or substitutes for active and passive less dependent on space assets. countermeasures. Even in the event of deploy- Regardless of whether salvage-fusing were ment of advanced ASAT weapons such as ex- employed, mutual deployment of singlepulse pendable single-pulse lasers against which 86

“shoot-back’ and passive measures might be based weapons. [A separate, classified appen- ineffective, postures and policies intended to dix to this report (Appendix D) contains a enhance deterrence could enhance security, al- more detailed discussion of the utility of mili- though they cannot guarantee security. tary satellites to the United States and to the U. S. S. R.] In pursuing security through deterrence, it is appropriate to develop retaliatory capabil- The second consideration—avoidance of cri- ities which place at risk targets of sufficient sis instability—precludes reliance on desta- value to deter attack and which do not exacer- bilizing weapons to provide retaliatory capa- bate crisis instability. The first of these con- bilities. Space-based ASAT weapons capable siderations implies that to deter ASAT attack, of instantly destroying several satellites, in- retaliation need not necessarily be “in kind”— cluding similar ASAT weapons, would be most i.e., against satellites. In fact, an ability to re- destabilizing unless salvage-fused but would taliate in kind, however thoroughly or swiftly, be prone to accidental firing if salvage-fused. would be inadequate to deter an ASAT attack By comparison, an ideal weapon for deterring if the attacking nation valued destruction of ASAT attack would be nonnuclear and hence enemy satellites more than survival of its own. usable at all levels of conflict without escalat- For example, if the U.S.S.R. developed a ca- ing the level of conflict. It could survive a pability to quickly destroy all on-orbit U.S. preemptive attack and destroy enemy assets satellites, then even if the United States could of sufficient value to deter an attack while destroy all on-orbit Soviet satellites in retali- causing little collateral damage. ation, the U.S. capability to mount such a retaliatory response —although valuable in the Diplomatic Measures event—might not deter a Soviet first use of ASAT weapons. Soviet leaders might judge In addition to the military measures dis- the continued deployment of U.S. MILSATS cussed above, diplomatic measures such as to be more detrimental to Soviet interests than arms control initiatives and negotiation of survival of Soviet MILSATS is valuable to So- “rules of the road” for space operations could viet interests. If this were the case, an ability be useful responses to foreign development of to retaliate against [more valuable] terrestrial threatening ASAT capabilities. The variety of assets would be required to successfully de- possible measures is great, and assessment of ter an ASAT attack. Such retaliatory capabil- their advantages is complicated; this topic is ities might be provided by terrestrial or space discussed in detail in chapter 6.

SUMMARY OF FINDINGS REGARDING ASAT CAPABILITIES AND COUNTERMEASURES

The most important conclusions which may 2. The inherent A SAT capabilities of exist- be drawn from the preceding discussion of ing nuclear weapons such as U.S. and So- ASAT capabilities and countermeasures are: viet ICBMS and Soviet ABM interceptor 1. Nonnuclear ASAT weapons which are missiles are substantial. Such weapons now deployed or being tested by the could pose a threat even to satellites in synchronous orbit, but are useful only at United States and the U.S.S.R. are limited in altitude capability and respon- the highest levels of conflict. siveness and can attack only a subset of 3. Technologies applicable to future ASAT currently deployed opposing MILSATS, weapons are so varied, and many so prom- although this subset includes important ising, that future ASAT weapons, if de- MILSATS. veloped, would be able to attack and dis- 87 — --

able virtually all MILSATS of current but not necessarily eliminate incentives types as currently deployed. Hence to to preempt but would increase risks of ac- maintain the survivability of constella- cidental attack. tions of future MILSATS, it will be nec- 7. A capability to confirm the occurrence essary that the development and deploy- and identify the perpetrator of an A SAT ment of such weapons be constrained by attack and to retaliate in proportion, but arms control or that future satellites be not necessarily in kind, might deter protected from them by passive or active ASAT attacks. A capability to retaliate countermeasures, or that a combination in kind—i.e., against the attacker’s sat- of these approaches be pursued. ellites-could contribute to deterrence, if 4. Of individual passive countermeasures this capability were survivable, but if this which might be used against advanced capability were vulnerable to ASAT at- ASAT weapons, only deception (use of de tack, it could undermine deterrence by coys) is likely to be effective against all posing an opponent an incentive to attack types of ASAT weapons, and deception preemptively. However, a capability to is likely to be economical (relative to the retaliate in kind would be inadequate to offense) only if the decoys, and the satel- deter an ASAT attack by an adversary lites they mimic, are lightweight and in- nation which values destruction of U.S. expensive. Use of deception in combina- satellites more highly than survival of its tion with maneuver, hardening, and own. proliferation might offer economical pro- 8. Strict arms control measures could not be tection for lightweight satellites. 5 Active countermeasures—electronic coun- expected to eliminate the inherent ASAT capabilities of weapons such as ICBMS termeasures, electro-optical countermeas- nor provide complete confidence that no ures, and shoot-back—would be ineffec- ASAT weapons have been developed and tive against an aggressive or preemptive deployed covertly. In an arms control re- surprise attack using expendable, single- gime which bans ASAT weapons, use of shot ASAT weapons (e.g., kinetic-energy, passive countermeasures would be re- directed-energy, and nuclear “space mines”). Actively defending keep-out quired to reduce the residual risk posed zones around critical satellites might be by weapons such as ICBMS. However, prohibiting the testing of A SAT capabil- able to protect such satellites against em- ities of weapons would preclude the at- placement of short-range space mines but not against advanced, long-range space tainment of confidence that certain types of advanced, nonnuclear ASAT weapons mines. would perform reliably if used and would 6. Of future ASAT weapons now foresee- therefore also reduce incentives to de- able, those which would be most effective velop such weapons or to attempt to de- if used in a preemptive or aggressive sur- ploy them covertly. A ban on testing prise attack—i.e., expendable, single-shot would also render more difficult, costly, ASAT weapons–would be space-based and risky any attempt to attain confi- and therefore subject to such attacks by dence, by covert testing, that other types similar weapons. The cost of protecting of advanced, nonnuclear ASAT weapons them from such attacks—which must nec- (e.g., ground-based lasers) would perform essarily be by passive means—would ex- reliably if used and would therefore also ceed the cost of attacking them. Such reduce incentives to develop such weap- weapons, if mutually deployed, would pro vide or increase incentives to attack ons or to attempt to deploy them covertly. preemptively in crises in which similar at- Prohibiting the basing in space of weapons tacks are anticipated. Salvage-fusing such with ASAT capabilities, to the extent that weapons. to fire if disturbed would reduce compliance with such a ban could be verified, 88 would forestall the creation of strong incen- spacecraft could reduce the ambiguity of such tives to attack such weapons preemptively provocative acts and thereby reduce the risk when a similar attack is feared. Even in the of ASAT attack resulting from misunder- absence of such strict restraints, if ASAT standing, while providing a legal basis for an- weapons are based in space, an agreement ban- ticipatory self-defense against ASAT weapons ning unauthorized close approach to foreign of short effective range. Chapter 5 ASAT Arms Control: History Contents

Page Introduction...... 91 Constraints Imposed by Treaties and Agreements en force ...... 91 Charter of the United Nations ...... 92 Limited Test Ban Treaty ...... 92 The 1967 0uter Space Treaty ...... 92 Strategic Arms Limitation Talks (SALT I&II)...... 93 Anti-Ballistic Missile (ABM) Treaty...... 94 International Political Barriers to ASAT Development...... 94 ASAT Negotiations—Past and Present ...... 95 Background ...... 95 1978-79 Negotiations...... , ., ., 96 Soviet Draft Treaties ...... 96 Congressional Interest in ASAT Arms Control and Executive Response...... 99 Current Activities in ASAT Arms Control ...... ,...... 101 Chapter 5 ASAT Arms Control: History

INTRODUCTION

This chapter discusses the constraints on Chapter 4 examined how certain passive and ASAT development imposed by the treaties active ASAT countermeasures might contrib- and agreements currently in force. It also ute to U.S. national security and provide pro- briefly examines the history of ASAT weap- tection for critical space assets. Building on ons development and deployment, and de- the historical background presented in this scribes the previous attempt by the United chapter, chapter 6 will examine the contribu- States and the Soviet Union to conclude a tion that ASAT arms control might make to treaty further restricting such weapons. The these same goals, analyzing a number of po- issue of ASAT weapons and ASAT arms con- tential ASAT arms control regimes and iden- trol, a politically volatile topic, has stimulated tifying those which might be appropriate for considerable interest in the U.S. Congress over the United States to pursue. The interaction the last several years; this chapter also dis- between technical countermeasures and arms cusses the history of the major pieces of leg- control is examined in chapter 7. islation in the 97th, 98th, and 99th Congresses (1981-85) which concerned ASAT negotiations and weapons development.

CONSTRAINTS IMPOSED BY TREATIES AND AGREEMENTS IN FORCE

To evaluate future space arms control meas- party to the 1967 Outer Space Treaty’ and the ures it is first necessary to understand the con- Limited Test Ban Treaty4 accept additional re straints that existing treaties and other inter- striations on their space activities. The United national agreements place on military space States and the Soviet Union agreed bilaterally activities. No single treaty fully specifies in the context of SALT I (the ABM Treaty5 which space activities are allowed and which and the Interim Agreement to limit offensive prohibited, and existing agreements do not ap- arms) not to disturb the function of satellites ply uniformly to all countries. All nations are used to verify compliance with those treaties presumably bound by the provisions of the and to forgo the development of space weap- Charter of the United Nations,’ customary in- ons to counter ballistic missiles. The relevant ternational law, and the “general principles of provisions of these instruments are discussed law recognized by civilized nations.’” States below.

1 As a general rule, only states party to a treaty are bound by its terms. An exception to this rule appears in Article 2 (6) of the U.N. Charter which provides: “The Organization shall “’Treaty on Principles Governing the Activities of States in insure that states which are not members of the United Na- the Exploration and Use of Outer Space, Including the Moon tions act in accordance the Principles (of the Charter) so far as and Other Celestial Bodies, ” 18 U.S,T. 2410; T. I.A.S. 6347. may be necessary for the maintenance of international peace “’Treaty Banning Nuclear Weapon Tests in the Atmosphere, and security. ” Charter of the United Nations, 1970 Yearbook in Outer Space and Under Water, “14 U. S.T. 1313, T. I.A. S. of the United Nations, p. 1001. See also: Ian Brownlie, Princi- 5433. ples of Public International Law (3d cd., 1979). “’Treaty Between the United States and the U.S.S.R. on the ‘Statute of the International Court of Justice, Art. 38, 1970 Limitation of Anti-Ballistic Missile Systems, ” Oct. 3, 1972, 23 Yearbook of the United Nations, p. 1013. U.S.T. 3435, T. I.A.S. 7503.

91 92

Charter of the United Nations6 or in space, of other nonnuclear components for such weapon systems. The power source Article 2(3) of the U.N. Charter directs na- could be tested underground on Earth,1° as are tions to “settle their international disputes by other nuclear weapons, and the nonnuclear peaceful means in such a manner that inter- components could be tested separately in national peace and security, and justice, are space. not endangered.” Article 2(4) requires that nations “refrain . . . from the threat or use of The 1967 Outer Space Treatyll force . . . in any . . . manner inconsistent with the purposes of the United Nations. ” It could Article III of the Outer Space Treaty states be argued that these statements and other that space activities shall be carried out in general principles of customary international accordance with international law “in the in- 7 law in some ways inhibit the use of ASATS. terest of maintaining international peace and security and promoting international co-oper- It is important to note that the responsibil- ation and understanding. ” This Article ex- ities imposed by Article 2 of the U.N. Char- presses the sentiment of the drafters that ter are modified by Article 51, which states, space be used to benefit mankind and contrib- “Nothing in the present charter shall impair ute to peace. the inherent right of individual or collective self-defense. ” Taken together, Articles 2 and In contrast to the general language of Arti- 51 do indicate general international censure cle III, Article IV of the Outer Space Treaty of the use of force, but do not limit specific establishes a clear prohibition against placing weapon systems. “in orbit around Earth any objects carrying nuclear weapons or any other kinds of weap- Limited Test Ban Treaty8 ons of mass destruction. ”12 Orbiting weapons using nuclear explosions for power would pre- The Limited Test Ban Treaty of 1963 pro- sumably be included. This provision does not hibits nuclear weapons tests “or any other nu- limit ground-based ASATS or ASATS which clear explosion “ in outer space, as well as in use conventional explosives or other means to the atmosphere or under water. The treaty destroy a target. Neither does it ban nuclear- therefore prohibits the testing, in space, of ex- armed “pop up” ASAT interceptors that otic ASAT weapons that would derive their ascend directly to their targets without enter- g power from a nuclear explosion —a conse- ing into orbit.13 quence probably not anticipated by the treaty’s drafters. The Limited Test Ban Treaty would not limit the development or testing, on Earth .— IOSubject to other treaty limitations-see previous note. “Supra, note 3. %upra, note 1. “According to Ambassador Arthur Goldberg, chief U.S. ‘Terrestrial international law is explicitly extended to space negotiator of the Outer Space Treaty, weapons of mass destruc- by Article III of the 1967 Outer Space Treaty, which states tion include “any type of weapon which could lead to the same that the exploration and use of outer space shall be conducted type of catastrophe that a nuclear weapon could lead to” (Hear- “in accordance with international law, including the Charter ings Before the Senate Foreign Relations Committee on Exec- of the United Nations. ” utive D, 90th Cong., 1st sess., p. 23. ) In 1948, the U.N, Com- ‘Supra, note 4. mission for Conventional Armaments advised the Security ‘An additional limitation on nuclear-pumped space weapons Council that the term ‘weapon of mass destruction’ would in- can be found in the “Threshold Test Ban Treaty” of 1974. Ar- clude, “atomic weapons, radio-active material weapons, lethal ticle 1 prohibits tests of nuclear weapons greater than 150 kilo- chemical and biological weapons, and any weapons developed tons in yield, bannin g even underground testing of any nuclear- in the future which have characteristics comparable in destruc- driven weapon requiring an explosion larger than that. The tive effect to those of the atomic bomb or other weapons men- Threshold Test Ban Treaty was signed by the United States tioned above. ” (Resolution adopted by the Commission for Con- but has yet to be ratified. “Treaty Between the United States ventional Armaments at its 13th meeting, Aug. 12, 1948. U.N. of America and the Union of Soviet Socialist Republics on the Security Council, S/C.3/32/Rev. 1, Aug. 18, 1948.) Limitation of Underground Nuclear Weapon Tests, ” reprinted ‘~esting of such weapons which involved detonating nuclear in, Arms Control and Disarmament Agreements, U.S. Arms warheads in space would be banned by the Limited Test Ban Control and Disarmament Agency (1982 cd.), p. 167. Treaty. 93

Article IX of the Outer Space Treaty directs monitor adherence to the Agreements. NTM nations to “undertake appropriate interna- is understood, though not explicitly specified, tional consultations” before proceeding with to include certain reconnaissance satellite sys- any activity that might cause “potentially tems. The SALT Agreements further state harmful interference with the activities of that “Each Party undertakes not to interfere other states in the peaceful exploration and with the [NTM] of the other Party” as long use of outer space. ” It is possible to argue that as these assets are operated “in a manner con- states developing ASATS (weapons intended sistent with generally recognized principles of to cause “harmful interference”) should do so international law. ” The SALT Agreements im- only after ‘‘appropriate international consul- plicitly sanction the use of satellites for veri- tations. ” Nonetheless, the vague wording of fication of treaty compliance and provide some Article IX and the forced nature of such an measure of protection against peacetime attack interpretation reduce the Article’s value as an on these assets. These Agreements do not, how- arms control provision.14 ever, restrict the development, testing, or deployment of ASAT systems capable of at- Taken together, the provisions of the Outer tacking NTM. In addition, whatever legal pro Space Treaty afford satellites some measure tection these Agreements provide is limited of legal protection against attack. The precise to systems used to verify the SALT Agree- nature of this protection is unclear since the ments. Other space systems used for combat treaty was not drafted for the specific purpose support during hostilities would not be pro- of limiting deliberate hostile activities. The tected under the SALT provisions. treaty clearly does not limit the development, testing, or deployment of nonnuclear weapons Article IX of SALT II prohibits the devel- capable of interfering with satellites of other opment, testing, or deployment of “systems nations; moreover, the U.N. Charter provision for placing into Earth orbit nuclear weapons for self-defense might be taken to permit such or any other kind of weapons of mass destruc- interference in some cases. tion, including fractional orbital missiles. ” This provision was included to limit the devel- Strategic Arms Limitation Talks opment of Fractional Orbital Bombardment (SALT I & 11)’5 Systems (FOBS), in which missiles enter partial Earth orbit and fly the long way around The verification provisions of SALT I and the Earth rather than taking the much more II state that the parties shall use “national direct trajectory of normal ICBMS. However, technical means” (NTM) of verification to this provision could also be read as expand- ing the prohibition of Article IV of the Outer liThe ‘‘Accident~ Measures’ Agreement of 1971 IW@IWS the Space Treaty. Whereas Article IV prohibits United States and the Soviet Union to “notify each other im- mediately in the event of . . . signs of interference with [missile only the act of orbiting nuclear weapons, Ar- warning systems] or with reiated communication facilities. ” ticle IX of SALT 11 would seem to prohibit However, this agreement places no limitations on the develop- in addition the development, testing and de- ment or use of ASAT capabilities. “Agreement on Measures to Reduce the Risk of Outbreak of Nuclear War Between the ployment of systems (e.g., launchers) to ac- United States of America and the Union of Soviet Socialist complish the orbiting of these weapons. So Republics, ” reprinted in U.S. Arms Control and Disarmament interpreted, Article IX could create an addi- Agency, Arms Control and Disarmament Agreements (Wash- ington, D. C.: U.S. Government Printing Office, 1982), p. 159. tional legal barrier to the development of “’’Interim Agreement Between the United States of Amer- —.——— ica and the Union of Soviet Socialist Republics on Certain Meas- armament Agreements (Washington, DC: U.S. Government ures with Respect to the Limitation of Strategic Offensive Printing Office, 1982), p. 246. Arms” (SALT 1) reprinted in, Arms Control and Disarmament The completed SALT 11 agreement was signed by President Agreements, U.S. Arms Control and Disarmament Agency Carter and GeneraI Secretary Brezhnev on June 18, 1979. Al- (1982 cd.), p. 139.; “Treaty Between the United States of Amer- though Senate consent to ratification has not been given, Presi- ica and the Union of Soviet Socialist Republics on the Limita- dents Carter and Reagan both declared that they would do noth- tion of Strategic Offensive Arms” (SALT 11), reprinted in U.S. ing to jeopardize the treaty as long as the Soviet Union abided Arms Control and Disarmament Agency Arms Control and Dis- by it. 94

orbital, nuclear-pumped, directed-energy ons “could perform a variety of missions, such weapons. as antisatellite or ballistic missile defense. ” For the purposes of the ABM Treaty, “an Anti-Ballistic Missile (ABM) Treaty’B ABM system is a system to counter strategic ballistic missiles or their elements in flight In the ABM Treaty, the United States and trajectory. “ Therefore, ASAT weapons would the Soviet Union agreed not to deploy anti-bal- be prohibited by the ABM Treaty if they were listic missiles except under the very limited capable of countering strategic ballistic mis- conditions set forth in the treaty .17 Each party siles. * Such systems are banned unless they also undertook not to “develop, test, or deploy are fixed, land-based and deployed at per- ABM systems or components which are sea- mitted sites. The testing of ASAT weapons based, air-based, space-based, or mobile of lesser capability would not be inhibited by land-based. ” the treaty. If an ASAT weapon became capa- The distinction between advanced ASAT ble of intercepting missiles, it would fall within and BMD technologies is not always clear. As the terms of the ABM treaty. This capability noted by Secretary of Defense Weinberger in test includes future systems having compo- a report to Congress, Ia directed-energy weap- nents “based on other physical principles” than those of the ABM system components 16’’ Treaty Between the United States of America and the (interceptors, launchers, and radars) described Union of Soviet Socialist Republics on the Limitation of Anti- in Article 11 of the treaty. However, the ABM Ballistic Missile Systems, ” supra, note 5. “Article III limits each side to two fixed, ground-based ABM Treaty does not control highly capable ASAT deployment areas (later reduced to one), each of which has limi- systems lacking ABM capability, and it does tations on radar facilities and interceptors and launchers. not clearly indicate how such capability is to Agreed Statement D provides that should ABM systems based on other physical principles than missile interceptors be devel- be inferred. oped in the future, these would be subject to discussion and agreement. Unless such systems were explicitly permitted by future agreement, they would continue to be banned. ‘UC. Weinberger, Fiscal Year 1985 Annual Report to Congress *The ABM Treaty is discussed in grater detail in OTA’S re- (Washington, DC: U.S. Government Printing Office, February port, Ballistic Missi/e Defense Technolo~”es, OTA-ISC-281, 1984), p. 263. app. A.

INTERNATIONAL POLITICAL BARRIERS TO ASAT DEVELOPMENT Although there are few clear international sures to limit the arms race, see U.S. and So- legal barriers to ASAT development, the de- viet cooperation in controlling space weapons sire of the United States to remain in some as one means to reduce international tension. way responsive to international opinion cre- It is important to note, therefore, that there ates certain inhibitions to the unrestrained may be a significant political or diplomatic pursuit of weapons that are based or operate cost to developing space weapons. in space. In the United Nations and other international fora, the United States and, to a Opposition to “space weapons” derives, in lesser extent the Soviet Union, have been crit- part, from the belief that space is a unique icized for their military activities in space. environment which must be preserved for Some view the “militarization” or “weaponi- “peaceful” activities and should be responsive zation” of space as breaking a de facto politi- to international controls. The “uniqueness” of cal taboo; others see it as a violation of cus- space is seen as deriving from the fact that tomary international law. Some of our allies, some space activities, such as remote sensing responding to strong domestic political pres- and satellite communications are inherently 95 global in effect; i.e., they pass over the terri- Having been nurtured for over 25 years, the tory of other countries and may require inter- idea that space is a unique environment which national coordination, such as frequency allo- should be used for peaceful purposes has come cation. These characteristics have resulted in to be considered by some to be a principle of the development of a number of successful in- customary international law. As a result, the ternational institutions such as the Interna- development of weapons which would operate tional Telecommunication Union (ITU), the in or through space has met with strong op- International Telecommunication Satellite position in international fora. Organization (INTELSAT), and the Interna- The 1982 General Assembly Resolution on tional Maritime Satellite Organization (IN- MARSAT). the “Prevention of an Arms Race in Outer Space” reflects this international concern. ’g The fact that certain space activities have The Resolution reaffirms the belief of the Gen- been the subject of international controls has eral Assembly that “space [activities] should fostered a belief among some that all space be for peaceful purposes and carried on for the activities should somehow require interna- benefit of all peoples, ” and notes “the impor- tional consent. In this view, an unrestrained tant and growing contribution of satellites arms race between the United States and the for . . . the verification of disarmament agree- Soviet Union in space is seen as threatening ments and . . . their use to promote peace, sta- the interests of nations not having strong bility and international cooperation. ” Point- space programs as well as being a threat to ing out the “threat posed by anti-satellite peace. systems and their destabilizing effect for in- The United Nations, and in particular its ternational peace and security, ” the Resolu- tion urges all states “to contribute actively to Committee on the Peaceful Uses of Outer the goal of preventing an arms race in outer Space (COPUOS), has been responsible for five international treaties dealing with space. Each space and to refrain from any action contrary to that aim. ” Finally, it requests the U.N. of these treaties emphasizes to some degree Committee on Disarmament to consider “the the necessity that the exploration and use of question of negotiating effective and verifiable space be for “peaceful purposes. In addition, many world leaders (including every President agreements aimed at preventing an arms race of the United States since Eisenhower), scho- in space. lars, and jurists have, since the beginning of the space age, emphasized the unique nature of space and its ability to contribute to peace and the common good. “’U. N.G.A. Dec. A 36192, .4ug. 11. 1982.

ASAT NEGOTIATIONS–PAST AND PRESENT

Background From 1964 until 1970, another such system was maintained on Johnston Island by the Air The first test of a weapon against a satel- Force; this system was formally decommis- lite was conducted by the United States in sioned in 1975. z0 1959 when a Bold Orion missile launched from a B-47 aircraft successfully passed within 20 miles of the U.S. Explorer VI satellite as it passed over Cape Canaveral. In 1963 and ‘(’Marcia Smith, “ ‘Star W’ars’: Antisatellites and Space-Based 1964, the U.S. Army operated a system of BMD” (Washington, DC: Library of Congress, Congressional Research Service, Issue Brief 11381123, Nov. 26, 1984); Paul nuclear-armed direct-ascent ASAT intercep- Stares, “Deja Vu: The ASAT Debate in Historical Context, ” tors on Kwajalein Atoll in the Pacific Ocean. ,4rms Control Toda)’, December 1983, p. 2. 96 — — — ——

The Soviet Union initiated a series of ASAT though neither side formally withdrew from tests in 1968 which continued through 1971.2’ the negotiations, after the Soviet invasion of Although the United States suspected that Afghanistan, the U.S. refusal to ratify the the Soviets were developing an “inspect and SALT II Treaty, and a general deterioration destroy” capability, this system was not seen of U.S.-Soviet relations, discussions never as posing so significant a threat to U.S. assets resumed. that a response was necessary. However, when The 1978-79 talks did not result in an ASAT the Soviets conducted another series of ASAT arms control agreement; however, they did tests between 1976 and 1978, U.S. officials be- clarify some of the concerns of the two par- gan to express concern. ties. The talks focused on two main topics: The Carter Administration adopted a “two- limits on ASAT use, and limits on the devel- track” policy. In March 1977, President Carter opment of ASAT capabilities.2G announced that he had suggested to the So- During the 1978-79 negotiations, as now, the viets that “we forgo the opportunity to arm different status of the U.S. and Soviet ASAT satellite bodies and also to forgo the opportu- 22 programs was a substantial impediment to nity to destroy observation satellites. ’ Also progress. The Soviet ASAT system was con- in that month, the Department of Defense an- sidered by the United States to be “opera- nounced that U.S. military space programs 23 tional, ” whereas the potentially more capable were being accelerated. American system had yet to be tested. A limited moratorium or treaty would have 1978-79 Negotiations given the United States time to conduct The Soviets responded positively to Carter’s ground-based research and development while proposal for ASAT negotiations and in March inhibiting Soviet ASAT weapons tests in 1978, agreement was reached on an explora- space. An indefinite test ban, on the other tory meeting. Three rounds of the ASAT limi- hand, might have locked the United States tation talks were held: June 8-16, 1978, in Hel- into a position of ASAT inferiority. sinki; January 23-February 16, 1979, in Bern; and April 23-June 15, 1979, in Vienna. The Soviet Draft Treaties third round of talks ended when the two sides In 1981 and again in 1983, the Soviets sub- felt they had gone as far as they could with- mitted draft space weapon treaties to the out further consultation and study in their 27 24 United Nations. U.S. experts disagree as to respective countries. According to Ambas- why the Soviets have continued to advocate sador Robert W. Buchheim, head of the U.S. space weapon arms control. One theory holds delegation for most of the 1978-79 ASAT that the Soviet interest is not in arms control, talks, the two delegations agreed that when but rather in propaganda. Since the Reagan either decided that it was ready to resume ac- Administration was not actively seeking limi- tive negotiations, the other party would be so 25 tations on space weapons, the Soviets could notified through diplomatic channels. Al- — portray the United States as being responsi- 21 Soviet S~ace Programs: 1976-$0, Committee Print, Senate ble for the escalation of the arms race and the Committee on Commerce Science and Transportation, 97th Cong., 2d sess., December 1982, p. 184. Z~The ~~ash~n~on Post, Mar. 10, 1977, p. A4. “For a more detailed discussion of the 1978-79 talks, see: 231 bid. Walter Slocombe, “Approaches to an ASAT Treaty, ” Space “Lynn F. Rusten, “Soviet Policy on Antisatellite (ASAT) Weapon~-The Arms Contro] Dilemma. 13hupendra .Jasani (cd.) Arms Control” (Washington, DC: Library of Congress, Congres- (I,ondon: Taylor and Francis, 1984), p. 149; and Lynn F. Rusten, sional Research Service, 84-670-S, June 22, 1984), p. 1. op. cit. 25’’Arms Control and the Militarization of Space, ” Hearings “’’Draft Treaty on the Prohibition of the Stationing of Weap- Before the Subcommittee on Arms Control, Oceans, Interna- ons of Any Kind in Outer Space, U.N. General Assembly, Dec. tional Operations and Environment of the Committee on For- A/36/192, August 1981; “Treaty on the Prohibition of the Use eign Relations on S.J. Res. 129, U.S. Senate, 97th Cong., 2d of Force in Outer Space and From Space Against the Earth, sess., Sept. 20, 1982, pp. 54-55. U.N. ~OC. A138/194, Aug. 26, 1983. 97

“militarization” of space. Another hypothesis below) served to shift some of the burden of is that the Soviets have a genuine interest in the “militarization” issue back to the Soviets. limiting ASAT technology because this is an area where the United States would be able Since their introduction at the United Na- to excel. Since the Soviets have clearly stated tions, a good deal of attention has been given their opposition to the Reagan Administra- to the language of the two Soviet draft trea- tion’s plans to develop spacebased BMD tech- ties. It is useful to examine these drafts since nologies, their interest in arms control in they provide valuable insights into how the space—especially after March 1983—could be Soviets have been thinking about arms con- intended to inhibit the progress of this program. trol in space. The United States refused to participate in 1981 Soviet Draft Treaty multilateral negotiation with the Soviets on The provisions of the 1981 and 1983 Soviet either the 1981 or 1983 draft treaties. What- draft treaties reflect the major issues raised ever the true reason or combination of reasons in the 1978-79 negotiations. Articles I and III, for Soviet interest in ASAT arms control, the the operative provisions of the 1981 Soviet Soviets have used this issue–and the U.S. re- draft - treaty, state: fusal to negotiate–effectively in their political propaganda. The Soviet position has been, I. The member states undertake not to put until recently, that their space program has into orbit . . . objects with weapons of been purely peaceful in nature. Since 1958, any kind, . . . and not to deploy such according to Soviet Foreign Minister Gromyko, weapons in outer space in any other way, the Soviet Union “invariably stated and con- including also on piloted space vessels of multiple use . . . tinues to state that space should be a sphere 8 III. Each member shall . . . not destroy, dam- of exclusively peaceful cooperation. “2 age, or disturb the normal functioning From an American point of view, the Soviet and not to alter the flight trajectory of propaganda seems absurd since the Soviet space vehicles of other member states Union has an “operational” ASAT and a very where the latter have . . . been put into orbit in strict accordance with . . . Arti- active military space program. From the point cle I. of view of many nonaligned governments, as well as important segments of the populations Because it prohibited only weapons sta- of our allies, the fact that the Soviet Union was tioned in orbit, the 1981 draft would not have as responsible for the “militarization of space” restricted the testing, development, and de- as the United States, or more so, did not lessen ployment of ground-based or air-launched the culpability of the United States for refus- ASATS. Accordingly, the United States and ing to negotiate. As a result, the Soviet prop- the Soviet Union could have kept their current aganda on the “militarization’ of space was ASAT systems and also pursued future tech- initially successful in enhancing the interna- nologies such as ground-based or air-borne tional image of the Soviets while fostering crit- directed-energy weapons. The 1981 draft icism of the United States. More recently, the treaty would, however, have prohibited the de inability of the United States and the Soviet velopment of space-based BMD systems. Union, in the summer of 1984, to come to an According to Article III of the 1981 draft, agreement regarding ASAT weapon and other parties would agree not to “destroy, damage, arms control negotiations (discussed in detail . or disturb the normal functioning and not to Z81bid. However, m May 29, 1985, in an interview b a west alter the flight trajectory of space vehicles. ” German reporter in Geneva, Col. Gen. Nikolai Chervov, a sen- Presumably, signatories to such a treaty could ior department head on the Soviet General Staff, claimed that agree as to the meaning of the words “de- the U.S.S.R. had successfully developed a direct-ascent satellite interceptor similar to that tested by the United States in stroy, ” “damage,” and “alter the flight trajec- the early 1960s and operational until the mid-1970s. tory. ” It is less clear that a quick consensus 98 — —.

could be reached on what would be inhibited in particular went beyond it in calling for a ban under the injunction against “disturbing the on all testing of ASAT systems and the elim- normal functioning. ” Would this prohibit in- ination of all existing ASAT systems (see ap- terference with ground stations or the use of pendix A). However, it also repeats many of electronic countermeasures such as jamming the themes of the 1981 draft and of the 1978- or spoofing? Had the treaty been negotiated, 79 negotiations. these issues would have certainly been the Article 1 prohibits the “use or threat of force subject of great attention and possible com- in outer space and the atmosphere and on the promise. Earth through the utilization of . . . space ob- Article II of the 1981 proposed treaty states jects” and the “use or threat of force against that space vehicles shall be used in “strict ac- space objects. ” The “use or threat of force” cordance with international law. This lan- language echoes the language of Article 2 of guage seems to reflect the often stated Soviet the U.N. Charter. Since by the terms of Arti- belief that certain space activities—e.g., the cle III of the Outer Space Treaty, the U.N. operation of direct-broadcast satellites-are a Charter already applies to space, it is unclear violation of national sovereignty. However, what this provision would add to existing in- under the terms of Article III, the only satel- ternational law. Article I does make it clear lites that would be denied the treaty’s protec- that: 1) space objects are not to be used to tion would be objects carrying “weapons of threaten objects in “outer space and the at- any kind. ” mosphere and on the Earth”; and 2) space objects themselves are not to be threatened. This 1983 Soviet Draft Treaty article would prohibit threats from space- In August 1983, when then Soviet Chairman based assets—e.g., ASAT or BMD weapons– Andropov met with several U.S. Senators he and threats to space-based assets, whether made the following statement: from ground-, air-, sea-, or space-based systems. . . . (T)he Soviet Union considers it necessary to come to an agreement on a complete ban Article 2 has five sections. Section 1 prohib- of tests and of deployment of any space- its testing and deploying space-based weap- based weapons for striking targets on Earth, ons; this goes well beyond the simple “no-use’ in the air and in space. provision of the 1981 draft, which is repeated Furthermore, we are ready, in the most rad- in section 2. Section 3 repeats the prohibition ical way, to resolve the issue of anti-satellite of the 1981 draft against destroying, damag- weapons—to agree to eliminate anti-satellite ing, disturbing the normal function or chang- systems already in existence and to ban cre- ing the flight trajectory of space objects of ation of new ones. other states. At the forthcoming session of the General Assembly of the United Nations, we will in- Under section 4 of Article 2, parties agree troduce proposals developed in detail on all not to “test or create new anti-satellite sys- zg these issues. tems and to destroy any anti-satellite systems As indicated by Chairman Andropov, on that they may already have. ” There is no at- August 22, 1983, Soviet Foreign Minister tempt in the treaty to define what constitutes Gromyko submitted a new draft treaty to the an “anti-satellite system. ” Presumably, it U.N. General Assembly .’” The new draft was would include both the proposed U.S. and cur- more comprehensive than the 1981 draft, and rent Soviet orbital interceptors. It is unclear . how systems, such as the Soviet GALOSH “’’Dangerous Stalemate: Superpower Relations in Autumn ABM, which might have some ASAT capabil- 1983, A Report of a Delegation of Eight Senators to the Sovi- et Union, ” Senate Dec. 98-16, Sept. 22, 1983, p. 28. ity, would be dealt with under the draft treaty. ‘“’’Treaty on the Prohibition of the Use of Force in Outer Space and From Space Against the Earth, ” U.N. Doc, A/38/194, Section 5 of Article 2 prohibits the “test or Aug. 22, 1983. use of manned spacecraft for military, includ- 99 — ing antisatellite, purposes. ” Because of the ● House Joint Resolution 607 (Moakley, D- limitations that this would place on the U.S. Mass. and 29 cosponsors), calling for the Space Shuttle, it is unlikely that the United immediate negotiations for a ban on space States would agree to such a provision. In any weapons of any kind. case, since the SALT agreements allow veri- The number of bills and resolutions on space fication by “national technical means” (NTM) weapons introduced in the 98th Congress and the Shuttle is the launch vehicle for Gov- (1983-84) rose dramatically, with all but one ernment payloads—including satellites used dying in committee.” The exception was for NTM—this provision would seem to con- S. J.Res. 129 (Pressler and 28 others), which flict with current Soviet and U.S. agreements. was reported favorably out of the Senate For- eign Relations Committee and significantly Congressional Interest in ASAT Arms modified before being introduced, and later Control and Executive Response withdrawn, as an amendment to the fiscal year 1985 DOD authorization bill. A resolution sug- Following the introduction of the two Soviet gesting that international cooperation in space draft treaties, the Reagan Administration ex- be pursued as an alternative to the arms race pressed no interest in negotiating these or any was passed by Congress and signed into law other limitations on ASAT weapons. As time passed, Members of Congress in both Houses (S. J.Res. 236; Public Law 98-562), but only after most of the language concerning the arms began to apply pressure on the Administra- race had been deleted. The most important action to halt ASAT testing and to begin negotiations with the Soviets. This pressure was tions of the 98th Congress resulted from amendments to the DOD authorization and applied most effectively in amendments to the Department of Defense authorization and ap- appropriation bills. propriations bills. The Fiscal Year 1984 DOD Authorization Bill The following resolutions concerning space While the House of Representatives was de- weapons were introduced in the 97th Congress bating the fiscal year 1984 DOD authorization (1981 -82).” None of them were reported out of bill (H.R. 2969), two amendments concerning committee or passed by either House: ASAT weapons were introduced. The first, in- Senate Resolution 129 (introduced by troduced by Representative George Brown (D- Pressler, R-S. Dak.) calling for resumption Calif.), would have denied procurement fund- of ASAT limitations talks. ing for the ASAT weapon; the second, intro- Senate Executive Resolution 7 (Pressler), duced by Representative Seiberling (D-Ohio), calling for negotiation of a protocol to the would have prohibited the flight testing of the 1967 Outer Space Treaty that would pro- ASAT until authorized by Congress. Both vide a complete and verifiable ban on amendments were defeated. ASAT development, testing, deployment, In the Senate, an amendment introduced by and use. Senator Tsongas and unanimously passed pro- Senate Resolution 488 (Matsunaga, D- hibited the expenditure of funds for tests of Hawaii)j calling for talks with the Soviet Union concerning the possibility of establishing a weapons-free international space “1.egislati~n not reported from committee in either House or Senate: station. I,egislation Opposed to Space Wreapons: H.J. Res. 87 (Kasten- meier, D-W’is. ); H.J. Res. 120 (Moakley, D-Mass. and 130 others); S J.Res. 28 (Tsongas, D-Mass. and 8 others); H. J.Res. 523 (I)icks, D-W’ash. and 58 othersl and 524 (Dicks and 55 others); 31 For a more detailed historv of congressional activity dur- 1l..J. Res. 53 I (Brown, D-Calif. and 96 othersj. Z,egislation in F’a\or of Space J{’capons: S.Res. 100 {W’allop, ing the 97th and 98th Congres~es, see Marcia S, Smith, “ ‘Star lt-W’jo. and 14 othersl: S, 2021 (.Armstrong, R-CO1O.I: H.Res. 215 Mrars’: Antisatellites and SpaceBased BhlD” (J$’ashington, DC: (t\’hitehurst, R-\”a. }, H. Res. 259 [Rennett, D-Fla. and 17 others:l: Library of Congress. Congressional Research Service. Issue 1{, R. 3073 ( Kramer, R-CO1O. and 13 others) Brief IB81 123, No\’. 26, 1984). Source; Sm]th, op. cit.; and Iiibrary of Congress SCORPIO database 100

explosive or inert ASAT weapons (i.e., exempt- space have been found to date that are judged ing directed-energy weapons) against objects to be in the overall interest of the United in space, unless the President determined and States and its Allies.” The report stated that certified to Congress that: 1) the United States the search for effective ASAT arms control was endeavoring in good faith to negotiate a was impeded by the “difficulties of verifica- treaty with the Soviet Union for a mutual, ver- tion, diverse sources of threats to U.S. and Al- ifiable, and comprehensive ban on ASATS; and lied satellites and threats posed by Soviet tar- 2) that pending such an agreement, such tests geting and reconnaissance satellites which were necessary for the national security. undermine conventional and nuclear deterrence, ” and it emphasized the necessity for the The Fiscal Year 1984 DOD Appropriation Bill development of a U.S. ASAT weapon. Following a proposal by Representative McHugh, the House Appropriations Commit- The Fiscal Year 1985 DOD Authorization Bill tee deleted the fiscal year 1984 ASAT procure ment funds pending a report from the Presi- When considering the fiscal year 1985 DOD dent on his policies regarding arms control in authorization bill, the House approved an space. The Senate Appropriations Committee amendment introduced by Representative took no similar action, but during floor debate, George Brown. The amendment prohibited the the Senate adopted an amendment introduced use of funds for ASAT testing against objects by Senator Tsongas requiring the President in space until the President certified to Con- to submit a report on the national security im- gress that the Soviet Union had conducted an plications of the Strategic Defense Initiative. ASAT test after the enactment of the bill. The House later accepted an amendment (offered In the course of the House and Senate con- by Representative Gore) to the Brown amend- ference on the appropriations bill, the con- ment which limited testing until the President ferees agree to provide $19.4 million for ad- certified that either the Soviet Union or another vance procurement for the ASAT program as foreign power had conducted such a test. proposed by the Senate, instead of no funds as proposed by the House. However, the con- The Senate Armed Services Committee rec- ferees direct that these funds not be obligated ommended that the fiscal year 1984 authori- or expended until 45 days following submis- zation language restricting ASAT tests be sion to Congress of a comprehensive report on relaxed to permit ASAT tests against objects U.S. policy on arms control. The appropria- in space provided only that the President cer- tions bill, as amended, was passed by both tified such tests to be essential for pursuing Houses and signed into law (Public Law 98- arms control arrangements. During floor 212). debate, the Senate adopted a compromise amendment offered by Senators Warner and President Reagan’s March 1984 Report on Tsongas that prohibited spending funds for ASAT Arms Control testing ASAT weapons against objects in space until the President certified to Congress: On March 31, 1984, the Reagan Administra- tion issued its “Report to the Congress on U.S. ● that the United States was endeavoring Policy on ASAT Arms Control,” thus satis- in good faith to negotiate a mutual and fying the requirements of the fiscal year 1984 verifiable agreement with the strictest DOD appropriation bill. The report stated that possible limitations on ASATS consistent the Administration was “studying a range of with the national security interests of the possible options for space arms control with United States; a view to possible negotiations with the So- ● that pending agreement on such a ban, viets. ” However, it concluded that “no ar- tests against objects in space were nec- rangements or agreements beyond those al- essary to avert clear and irrevocable harm ready governing military activities in outer to the national security; 101

● that such testing will not constitute an The Administration also announced that in irreversible step which will gravely impair addition to discussing space weapons it in- prospects for negotiations; and tended “to discuss and define mutually agree that testing is fully consistent with U.S. able arrangements under which negotiations obligations under the ABM Treaty. on the reduction of strategic and intermediate range nuclear weapons can be resumed. 36 With some minor changes, the Warner- However, the Administration stressed that Tsongas amendment was adopted in the there were “no preconditions on the U.S. will- House and Senate conference report. ingness” to discuss the entire range of arms The Fiscal Year 1985 DOD Appropriation Bill control issues. Fiscal year 1985 appropriations for the De- The Soviets objected to discussing strate- partment of Defense were included in the Con- gic and intermediate-range missiles at the tinuing Appropriation Bill (Public Law 98- same time as space weapons. The Soviets pro- 473). The appropriation bill, as enacted, re- posed that the parties publish a joint public flects the compromise reached on the DOD au- announcement that would define the purposes thorization bill. The only differences are that of the talks as being limited to the subject of no tests against an object in space are per- space weapons and would endorse the concept mitted before March 1, 1985, or 15 days after of a moratorium on testing. The United States the President submits the required certifica- responded that it was prepared to talk about space weapons but that it was not prepared tions, whichever is later, and no more than 37 three tests against objects in space are per- to agree to a moratorium. The Soviets re- mitted in fiscal year 1985. jected the U.S. position and declared that it made the talks “impossible. “38 Although the U.S. Administration sent new messages mod- Current Activities in ifying and “clarifying’ its initial stand, these ASAT Arms Control too were spurned by the Kremlin. On June 29, 1984, about 3 months after the In the weeks following the initial exchanges President’s March 31 report had been released, there was little communication between the the official Soviet news agency Tass announced parties. The real argument seemed to be over that the Soviet Government had offered to which side would take the blame for refusing start talks “to prevent the militarization of to negotiate. No meeting was held in Septem- 3 outer space. “3 “To provide favorable condi- ber although both Washington and Moscow tions for the achievement of agreement, ” Tass continued to express interest in arms control reported that the Soviet Union was prepared, in space. “to impose on a reciprocal basis a moratorium on the tests and deployment of these weapons, Six months later, on January 8, 1985, U.S. starting with the date of the opening of the Secretary of State George Schultz and Soviet talks. 34 The Soviets suggested that such Foreign Minister Andrei Gromyko concluded meetings should take place in Vienna in Sep- 2 days of talks concerning the structure of fu- tember 1984. ture arms control negotiations. They jointly released a communique indicating that plan- In response, the Reagan Administration ning would commence on “the forthcoming stated that it was now ready to “discuss and U.S.-Soviet negotiations on nuclear and space seek agreement on feasible negotiating ap- arms” on “a complex of questions concerning proaches which could lead to verifiable and ef- space and nuclear arms, both strategic and in- fective limitations on antisatellite weapons. 35

“’’Soviet and U.S. Statements on Space Weapons Negotia- “Ibid. tions, ’ New York Times, June 30, 1984, p. 4. “’’Soviets Say U.S. Makes Talks on Space ‘Impossible’, ” The “Ibid. Washington Post, July 28, 1984, p. Al. ‘bIbid. “Ibid. 102 termediate range . . . The objective of the ne- been fulfilled.40 President Reagan’s decision to gotiations will be to work out effective agree- test the U.S. MV ASAT weapon against an ments aimed at preventing an arms race in object in space has reinvigorated congression- space” along with constraining terrestrial al debate on the ASAT issue. arms and increasing strategic stability.3g The Soviet response to the U.S. ASAT pro- Negotiations between the United States and gram has fluctuated. In 1983, President An- the Soviet Union began in Geneva in March dropov implied that the U.S.S.R. would re- 1985. Throughout these negotiations, the So- scind its self-imposed moratorium on ASAT viet delegation has insisted that the termina- testing if the United States began its ASAT tion of President Reagan’s Strategic Defense test program. Then, in May 1985, in an inter- Initiative is a necessary first step to any review with a West German reporter, Col. Gen. duction in offensive arms. U.S. negotiators Nikolai Chervov, a senior department head of have, for their part, argued that advanced bal- the Soviet General Staff, stated that the listic missile defense systems could provide a U.S.S.R. would rescind its moratorium if the means by which both parties could safely ne- United States completed testing the F-15 gotiate deep reductions in their nuclear ar- launched ASAT weapon. Most recently, the senals. As a result of this deadlock, both sides official Soviet news agency Tass, said that if appear to remain far from agreement on anti- the United States “holds tests of antisatellite satellite limitations. weapons against a target in outer space, ” the Soviet Union “will consider itself free of its On August 20, 1985, pursuant to the Fis- unilateral commitment not to place antisatel- cal Year 1985 DOD Authorization Act (dis- ’ lite weapons in space. cussed above), the President certified that the four requirements set out by Congress had ‘“Presidential Determination No, 85-19 of August 20, 1985, Federal Reg”ster, vol. 50, No. 165, Aug. 26, 1985, pp. ‘“Statement text from The Washington Post, Jam 9, 1985, 34441-34443. p. A14. 4’Wtishington Post, Sept. 5, 1985, p. A-17. Chapter 6 ASAT Arms Control: Options Contents

Page Introduction...... 105 Provisions Restricting ASAT Testing ...... 106 Monitoring Compliance With a Test Ban...... 106 Utility of an ASAT Test Ban ...... 109 Provisions Restricting ASAT Possession or Deployment ...... ,..112 Monitoring Compliance With Limitations on Possession and Deployment ...... 112 Utility of Limitations on Possession and Deployment ...... 113 Provisions Restricting ASAT Use ...... 114 Monitoring Compliance With a ’’No Use” Agreement ...... 115 Utility of a”No Use’’ Agreement...... 115 Provisions Restricting Spacecraft Operation and Orbits...... 116 Monitoring Compliance With a ’’Rules of the Road” Agreement ...... 118 Utility of a ’’Rules of the Road’’ Agreement ...... 118 BMD and ASAT Treaties of Limited Duration ...... 119 Compliance Monitoring, Verification, and Recourse ...... 120 Monitoring ...... 120 Interpretation...... 121 Assessment ...... 121 Recourse ...... 122

Table Table No. Page 6-1. Sensor Technology for Compliance Monitoring ...... 110 Chapter 6 ASAT Arms Control: Options

INTRODUCTION This chapter explores how various ASAT can the the United States monitor Soviet com- arms control provisions might affect the long- pliance? Do the Soviets intend to cheat, and term national security interests of the United if so, can they? What recourse would the States. The interaction between these arms United States have if faced with either clear control provisions and the unilateral satellite or ambiguous Soviet violations? Is the United survivability measures that the United States States better off pursuing arms control, tech- might pursue is discussed in greater detail in nological superiority, or some combination of chapter 7. Four types of arms control are pre- both? What will be the response of our allies sented below: restrictions on ASAT testing, to new development programs or arms control possession, use, and “rules of the road’ for proposals? These issues are discussed below, space. Each of these provisions is described both in the context of specific arms control and an assessment is given of its ability to pro- provisions and in a more general discussion tect U.S. space assets and contribute to other of monitoring treaty compliance. long-term U.S. goals. Potential conflicts be- Most of the provisions discussed in this tween ASAT arms control and the develop- chapter would require the United States and ment of military capabilities (e.g., the U.S. MV the Soviet Union to enter into a bilateral agree- ASAT program and the Strategic Defense Ini- ment to limit A SAT weapons development. As tiative) are also examined. a result of the technologies involved, their the- The development of anti-satellite weapons ater of operation, and the closed nature of So- poses a significant threat to the military sat- viet society, it is unlikely that the United ellites of both the United States and the So- States could monitor Soviet compliance with viet Union. These military satellites, in turn, complete certainty. The United States can provide information and services which can be know only part of what the Soviet Union does threatening to either side. Here lies the inher- and little or nothing about what it intends; ent difficulty in arriving at acceptable A SAT therefore, any arms control agreement in- arms control agreements-given the choice, volves some degree of risk. For the purposes the United States would like to protect its own of this discussion, the value or danger of a par- satellites while eliminating any military threat ticular arms control provision is measured by posed by Soviet satellites. ] Since such a one- its likely impact on U.S. national security after sided advantage is not possible, it is reason- allowance is made for possible covert Soviet able to examine whether there are mutual re- violations. In other words, given the risks of en- straints that would contribute to national tering into an agreement with the Soviets, are security and protect U.S. satellites, yet allow we better off with or without a particular pro- an adequate response to the threat posed by vision?z Soviet satellites. This chapter focuses primarily on bilateral The debate over ASAT arms control con- treaties of unlimited duration. Other arrange- tains many familiar themes: To what extent ments for ASAT constraints, such as multi- — ‘ Not all So~riet military satellites threaten the United States, z 1 t is important to note that ‘‘risk, as it is used here, does Presumabljr, the L)nited States would like the So\iet IJnion to not imply merely the probability that the Soviets can or would retain some reconnaissance and earl?’ warning satellites since \.iolate a particular provision of an A SAT agreement. Rather, these satellites contribute to stability b~ allowing verification risk signifies both the probabilit~’ that the Soviets would vio- of arms control agreements and by assuring the So\,iets that late the agreement and the threat to U.S. national security that the} are not under nuclear attack, would likel~ result from such a Soviet violation.

105 lateral agreements, joint declarations, executive ity and primarily to formal treaties of un- agreements or even unilateral declarations, limited duration because they are the hardest might also be in the national interest. How- to obtain and have the most lasting effect on ever, this report is limited exclusively to national policy and programs. bilateral agreements for the sake of simplic-

PROVISIONS RESTRICTING ASAT TESTING

An agreement that established limits on GALOSH was an ASAT or if it could function testing could be a useful means by which to as an ASAT, but would simply ban the test- prevent the development of reliable, dedicated ing of this system as an ASAT. ASAT systems. The effectiveness of test re- More limited “no-test” agreements could strictions is assumed to derive from the nat- also be used to inhibit the development of spe- urally conservative nature of military plan- cific types of ASATS or to place restrictions ners. Many informed observers believe that, on certain types of testing. Such a treaty except when forced by necessity, Soviet mili- might be used to ban the testing of only ASAT tary planners would be reluctant to rely on weapons that would be based in space. Alter- systems that have not been tested near their natively, it might be used to ban the testing full capabilities, particularly in situations of specific space-based ASAT weapons (e.g., where the stakes are high, second chances may directed-energy weapons or space mines) not come, and the penalties for failure could thought to be particularly destabilizing. Such be severe. a ban might also limit ASAT testing to low A test ban would prevent the testing which altitudes to protect critical early warning and would increase confidence in new ASAT weap- communication satellites that are in higher ons or, at minimum, would force testing to be orbits. done covertly, under less than optimal condi- All of these examples of limited test bans tions. In either case, the result would be to could be further modified by agreed limita- erode the confidence that an ASAT system tions on allowable numbers of tests. For ex- would work as planned, when needed. ample, the United States and the Soviet Un- There are several ways to frame a test ban. ion might agree to limit themselves to only 10 The most comprehensive would be a ban on tests over the next 5 years, or to a set num- all “testing in an ASAT mode. ” For the pur- ber (either constant or declining) of tests per poses of this discussion, “testing in the ASAT year for the duration of the agreement. mode” would include tests of ground-, sea-, air-, or space-based systems against targets Monitoring Compliance With in space or against points in space. Testing of a Test Ban ASAT systems or components on the ground would not be prohibited. Such an approach In past bilateral agreements between the would avoid both the necessity of defining an United States and the Soviet Union, the So- ASAT weapon and of restricting systems that, viet Union has tended to take advantage of although not designed as ASATS, might have treaty ambiguities and to engaged in activi- some inherent ASAT capability. For example, ties that—although sometimes difficult to it is possible that the Soviet GALOSH ABM characterize-bordered on treaty violation.3 It system might have some ASAT capability. An is prudent, therefore, to assume that should agreement that banned all “testing in an ASAT mode” would not require the United ‘There is reason to believe that the Krasnoyarsk radar, when States and the Soviet Union to agree whether complete and ready for o~ration, will violate the ABM Treaty. an ASAT test ban be negotiated, the Soviets though large, is relatively well determined and would comply only to the extent that the is amenable to close inspection by spacebased United States was able to verify its compli- photographic reconnaissance satellites. The re- ance. This being the case, it is important to gion where space activities must be monitored examine some of the problems associated with starts at altitudes of about 100 km and can monitoring the wide range of Soviet activities range well past geosynchronous orbit at 36,000 that might be related to A SAT weapon devel- km. In addition, advanced ground-based ASATS opment. could be located anywhere in the Soviet Un- ion and air-based ASATS might even operate Scope of Monitoring Task from non-Soviet airfields. One barrier to verifying compliance with a Although the volume of space is indeed test ban is the enormous volume of space large, spacebased ASAT activities must start where illicit activities might be conducted. on the ground. Relevant ground sites, includ- Verification of compliance with a SALT or ing launch facilities, can be observed by an ex- START arms control agreement involves intensive array of U.S. monitoring facilities; spection of a number of areas in the Soviet Un- launches of ICBMS and similar vehicles from ion or its immediate airspace. This area, al- Soviet territory can be detected. To some ex- 108 tent, the problems created by the large volume and the physical differences between per- of space are offset by the fact that space is mitted and prohibited satellites may be small. transparent and accessible to monitoring. Cur- Although the annual number of Soviet rent weaknesses in ground-based surveillance launches is large, the number of new satellites systems can be mitigated by putting surveil- or satellites engaged in “unusual activities” lance systems into space. is relatively small. Even if U.S. national tech- If the Soviets were to develop air-based, nical means of verification could not by direct ground-based, or ‘“pop-up” directed-energy observation distinguish between space mines weapons, these would require extensive test- and normal satellites, other indicators, such ing. It is likely that some portion of this test- as orbital parameters, proximity to other— ing could be conducted out of the sight of (e.g., particularly U.S.—satellites, and other sources indoors or underground) U.S. monitoring as- of intelligence might supply the needed infor- sets. However, full development would prob- mation. If in addition to a test ban the treaty ably require some in-space testing against tar- also included some mechanism for resolving gets. Possible targets could, in principle, be ambiguities —e.g., the Standing Consultative monitored to see if they are being illuminated Committee established in SALT I–the prob- by strong lasers, are giving off gases, are be- lem might be further resolved. ing unexpectedly accelerated, or are emitting Assuming that the difficulties associated unusual signals. Air- and ground-based sys- with deliberate ASAT systems were resolved, tems might be detectable by national techni- it would still be necessary to reach some agree cal means. Nonnuclear, spacebased systems ment concerning tests of advanced, ground- would be quite large and might emit detecta- based, BMD systems. Should conventional ble amounts of hydrogen fluoride or other ground-launched BMD systems be developed gases. —similar to the system recently demonstrated in the U.S. Homing Overlay Experiment (HOE) Problems of Discrimination —they may have some limited ASAT capa- Verifying treaty compliance is complicated bility. by the growing number and variety of Soviet space launches. Although the launch rate may Covert Development decrease in the future as the Soviets develop There are numerous ways for the Soviets to longer lived satellites, space surveillance re- engage in covert ASAT development. It is pos- quires a body of experience with each addi- sible that space mine or orbital interceptor tional type of satellite in order to classify its tests could be masked as legitimate rendez- function and discriminate between unusual vous operations or satellite repair missions. activity and routine behavior. The functional ASAT weapons might be directed against characteristics distinguishing ASAT weapons, points in space or space debris, thereby obviat- such as space mines, from other satellites may ing the need for recognizable target satellites. not be readily observable. Some occurrences ASAT vehicles or their targets could be in- might have multiple interpretations. For ex- strumented to store test data for broadcast ample, a satellite fragmenting in orbit could over the Soviet Union or for deorbit in a reen- be accidental, the test of a self-destruct mech- try capsule, thereby preventing the United anism (either to avoid capture or to prevent States from intercepting test information. large components from falling back to Earth), 4 Nuclear-armed ICBMS or ABM launchers or the test of a space mine. All national tech- such as the Soviet GALOSH might also be nical means have imperfect discrimination, tested (though not detonated) in a manner which would be difficult to characterize. Rela- @ne could, of course, ban all deliberate explosions in space. If such a ban were made part of a more general test ban, there tively low-powered lasers capable of blinding would be less ambiguity to resolve. satellite sensors are already available and 109

States needs to concentrate its verification efforts. In any case, it is likely that an ASAT test limitation agreement would provide the means by which parties could inquire about suspicious activities.

Utility of an ASAT Test Ban Considering both the limitations of U.S. monitoring capabilities and the possible ill- intentions of the Soviet Union, what then is the value of an ASAT test ban? To answer this question completely, one must examine the specific test bans being considered in combination with possible technical countermeasures (this is done in chapter 7). However, some preliminary generalizations can be helpful. Some of the satellites that the United States relies on for critical information are now vulnerable and few in number. With respect to these specific systems, a small degree of So- viet cheating under a test ban agreement might have a significant effect on U.S. secu- Photo credft U S Department of Defense rity. On the other hand, the United States has Artist’s conception of the nonnuclear ABM interceptor been quite successful at monitoring past So- recently tested i n the Homing Overlay Experiment viet space activities and the deployment of (HOE). The current Soviet GALOSH nuclear ABM interceptor or future, nonnuclear systems based on more capable monitoring assets—e.g., space- HOE technology could complicate the process of based surveillance systems–could substan- monitoring an ASAT weapon test ban. tially aid the process of treaty monitoring. It is important to note that modest satel- might be tested without being clearly identi- lite survivability measures would reduce the fied as being ASATS. risk posed by current ASAT weapons and It is, on the other hand, possible to exagger- could do much to reduce the risk posed by c- ate the threat posed by covert development. vert weapons development. In the absence of The United States is sufficiently familiar with an agreement limiting ASAT weapon devel- the operational characteristics of the current opment, the United States must still monitor generation of Soviet ASAT interceptors to Soviet activities but modest survivability make its covert testing unlikely. The develop- measures might not be effective. Without limi- ment of a new system would require an exten- tations, advanced ASATS would pose a greater sive testing program, some portion of which risk to a larger number of satellites and fail- we would almost certainly identify. New or un- ure to effectively monitor these advanced usual orbiting vehicles would be noticed, espe- ASATS could create a significant danger to cially maneuvering ones. Monitoring equip- U.S. national security. ment could be developed that would detect the laser illumination of Soviet satellites, and Comprehensive Test Ban which could aid in monitoring Soviet directed- A ban which prohibited all testing “in the energy facilities. (See table 6-1, below). Soviet ASAT mode” would severely reduce the likeli- efforts to hide covert testing might serve to hood that the Soviet Union could successfully narrow down the regions where the United develop advanced, highly capable ASAT weap- 110

Table 6-1 .—Sensor Technology for Compliance Monitoring

Prohibitable action Observable Sensors ASAT attack: Attack sensors: KEWa impact ., ...... acceleration accelerometers Pulsed HELb irradiation . . . . acceleration accelerometers Continuous HEL irradiation ...... heating thermistors NPBC irradiation ...... ionization ionization detectors Keep-out zone penetration . . . position of thermal radiation source (ASAT) space-based LWIRd thermal image~ f Interception test ...... positions of thermal radiation sources space-based LWIR thermal image~ f (ASAT and target) NPB ASAT operation ...... thermal radiation from ASAT space-based LWIR thermal imagere f HEL ASAT operation ...... thermal radiation from ASAT space-based LWIR thermal image~ f Irradiation of target with NPB ...... gamma radiation from target gamma-ray spectrometer Irradiation of target with pulsed HEL ...... thermal radiation from target space-based LWIR thermal imager Irradiation of target with pulsed HEL ...... reflected radiation from target space-based multispectral imager Irradiation of target with continuous HEL ...... position of thermal radiation source (target) space-based LWIR thermal imager Irradiation of target with continuous HEL ...... reflected radiation from target space-based multi spectral imager Nuclear explosive aboard satellite ...... gamma radiation from fissile or fusile gamma-ray spectrometer (and optional nuclei activated by cosmic radiation or by particle beam generator) particle beams aKlnetlc.energy weapon bHigh-energy laser cNeutral particle beam. dLong.wavelength infrared f?The LWlR telescope on the Infrared AStrOnOnll~al satelllte (lRAs) e~ernpllfles demonstrated space-based ttleunal Irnager technology, this Instrument iS described in Astrophys/ca/ Journa/, 278 (1, Pt 2), L1 .L85, Mar 1, 198-4 (Spectai Issue on the Infrared Astronomical Satelllte) fRadar and passive radio direction.finding methods could also be useful for tracking, If hiding measures are not employed by the penetrating Spacecraft LWIR tracking is emphasized here because it is difficult to counter by such measures. gA target Irradiated by a high-energy neutral particle beam will emit gamma rays, neutrons, and other observable part! cles, Just as !t WI II, at a slower rate, when bombarded by natural cosmic rays These gamma rays could be detected by a gamma-ray spectrometer such as those which have been earned by Soviet Venus Ian and lunar landers and by US NASA Ranger and Apollo spacecraft (NASA report SP.387, pp 3.20) ens. The categories of weapons eliminated isting system would pose some threat to the might included space mines capable of “shadow- other side. Over time, a comprehensive test ing” valuable military assets in any orbit, or ban would gradually erode each side’s confi- directed-energy weapons with kill radii of hun- dence in its respective weapons, thereby reduc- dreds to thousands of kilometers. In the ab- ing the possibility of their use. If a test ban sence of an agreement limiting the develop- were combined with additional restrictions on ment of these weapons, each side might seek possession or deployment, this might result continually more effective means to attack in somewhat greater security. threatening satellites and to defend valuable A comprehensive test ban would be less ef- assets. This could result in a potentially fective at reducing the threat posed by weapon destabilizing arms race in space. The “instan- systems with “inherent” ASAT capability. taneous kill” ability of the most advanced ICBMS, SLBMS, and ABM interceptors with ASATS would be destabilizing in a crisis, since nuclear payloads are examples of systems with each side would have the incentive to “shoot inherent ASAT capability. Although these first” or else risk the loss of its space assets. systems lack the kind of guidance necessary A comprehensive test ban would require to intercept a satellite with great precision, the both the United States and the Soviet Union long-range destructiveness of their nuclear to cease testing their current generation of payloads makes them potentially effective ASAT weapons. The Soviet ASAT is already ASATS. However, some of the ASAT threat considered operational. Assuming the United posed by nuclear weapons is offset by their States also had an operational ASAT when the very nature. The collateral physical, political, agreement entered into force, each side’s ex- and military consequences of using nuclear 171

ICBMS or ABMs as ASATS could well deter their use in most conflicts short of a terrestrial nuclear war. The Shuttle’s recent success at retrieving and refurbishing satellites strongly suggests the ASAT potential of future maneuverable spacecraft. However, the range, effectiveness and reaction time of even advanced maneuverable systems would be substantially less than that of future dedicated ASATS. Although the development of maneuverable spacecraft would not be inhibited by most ASAT testing limitations, some limits could be placed on operating them in an ASAT mode. The Soviet draft treaties and the 1983 unilateral Soviet moratorium on ASAT testing suggest that the Soviets would be willing to negotiate about a comprehensive ASAT test ban. To date, the U.S. response to Soviet sug- gestions has been to point out that since the Soviets have an “operational” ASAT and the U.S. testing program has just begun, a comprehensive test ban would prevent the United States from ever having a reliable interceptor ASAT and would increase the threat posed by a Soviet “breakout.” Nonetheless, the United States has continued to express interest in ASAT negotiations and has not ruled out the possibility that it would agree to some kind . of test limitations.

Limited Test Bans Photo credft U S Department of Defense Should a comprehensive test ban be consid- Ocean recovery of what is believed to be an unmanned ered undesirable or nonnegotiable, it might scale model of a new Soviet space plane. The development still be worthwhile to limit testing to the cur- of maneuverable spacecraft would not be inhibited by rent generation of ASATS or to ASATS only most ASAT testing limitations, but some restrictions might be placed on operating such spacecraft capable of attacking satellites in low-Earth or- “in an ASAT mode. ” bit. A ban which limited each side to testing its current ASAT would have three advan- If a limited test ban could restrict each side tages: 1) a ban on testing new types of ASATS to its current, low-orbit, ASAT capability, it would reduce the likelihood that advanced would, in effect, create high-altitude “no at- ASATS, such as space mines or space-based tack zones. This might encourage adver- directed-energy weapons, would be developed; 2) the threat to critical early warning and com- saries to move some Earth monitoring space munication satellites would be diminished; and assets into those zones. The development of high-altitude data collection systems would re 3) the United States would retain the ability to negate Soviet low-orbiting, targeting, and data collection satellites judged to pose a ‘If advanced directed-energy weapons with kill radii of thousands of kilometers are developed, such “no attack zones” might threat to U.S. surface forces. be meaningless. 112 —

quire considerable time and expense. For the the range to the target. The substantial in- next decade and perhaps beyond nations crease in range necessary to take advantage would probably be forced to operate their cur- of a high-altitude “no-attack’ zone would se- rent low-altitude systems. verely degrade the performance of current systems. It is possible that, over time, improve- Although it is possible that some reconnais- ments in technology could solve the problems sance satellites might be able to function from created by the increase in range. Nonetheless, higher orbits with some degradation of per- by the time this occurred new ECM and EOCM formance, radar satellites-useful in tracking capabilities might also be developed that could surface ships-would have substantially greater help to negate systems taking advantage of difficulty. Current systems employ active ra- high-altitude “sanctuaries.” dar, which means that the strength of the return signal decreases as the fourth power of

PROVISIONS RESTRICTING ASAT POSSESSION OR DEPLOYMENT

An agreement which sought to restrict the Many types of limited-possession regimes possession or deployment of ASAT weapons can be imagined. The United States and the could be either comprehensive or limited. A Soviet Union might decide to keep the ASATS comprehensive ban might prohibit the posses- they are currently testing, but prohibit the sion or deployment of any deliberate “anti- possession or deployment of more advanced satellite system. A limited ban, on the other systems. Alternatively, each side might be al- hand, might allow the possession of some lowed to have one designated system in addi- ASAT weapons but not others, or establish tion to the one they are currently testing; the limitations on allowable ASAT capabilities or capabilities of this additional system might or on the number and kind of deployments. might not be limited (e.g., low-Earth orbit capability only). Still another regime might limit In order to establish a comprehensive ban the parties to ground-based ASAT weapons on the possession or deployment of ASAT and ban possession of weapons that would be weapons, it would first be necessary to come based in space. to an agreement as to what exactly was being banned. As explained above, the existence In all of these limited-possession regimes ad- of systems that have an inherent ability to at- ditional restrictions on the number and loca- tack satellites complicates the process of elim- tion of allowable ASAT deployments could be inating all ASAT capability. A ban on all sys- added. tems with ASAT capabilities would be so broad as to be unworkable since it would in- Monitoring Compliance With clude ICBMS, SLBMS, ABMs, and maneuver- Limitations on Possession and able spacecraft such as the Shuttle. On the Deployment other hand, a ban on deliberate ASAT systems alone might allow the development of non- A comprehensive ban on the possession or ASAT systems having sophisticated ASAT deployment of the existing Soviet ASAT capabilities. For this reason, the most effec- weapon would raise some important monitor- tive comprehensive ban on possession and de- ing problems. The launch vehicle for the So- ployment would probably be one which was viet ASAT is used in several other non-ASAT also accompanied by a prohibition on testing roles. These launchers will remain available non-ASAT systems in an ASAT mode. even if the Soviet ASAT weapon is banned. 113

Since the ASAT weapon itself is small, it the U.S. ASAT weapons; 2) the fact that the would be difficult for the United States to ver- lack of possession or deployment could not be ify with high confidence that the Soviets had monitored with high confidence; and 3) the fear not clandestinely retained a stockpile. that a ban on possession and deployment— even if monitored with high confidence—would A limited possession ban that granted either not eliminate the knowledge of how to build side the right to possess and deploy the ASAT these systems, and that the forces might be weapon it was currently testing would raise reconstituted at some time in the future. fewer verification problems. Significant Soviet cheating would involve covertly testing and Balancing these three concerns is the under- developing a new and unproven advanced standing that for the Soviets to retain some ASAT weapon, rather than simply hiding an A SAT weapons in violation of a possession or existing system. As discussed above, it is deployment ban would not in itself be threat- likely that such a development program would ening—they must also be able to use these include some testing requirements that were A SAT weapons in a way that is militarily sig- observable. nificant. Differences of opinion exist as to the military significance of minor violations of a Given the small size of the current Soviet A SAT weapon, restrictions on the number of ban on possession and deployment. Some ar- A SAT weapons that could be deplcyed at each gue that the Soviets must be able to launch a sufficient number of A SAT weapons with launch site would be difficult to monitor in the sufficient rapidity to gain an important mili- absence of onsite inspection. Even onsite in- tary advantage. To do this, the ASAT weap- spection would not provide complete security, ons and launch vehicles would have to be pre- since ASATS could be covertly stored and eas- mated and held in readiness, activities that ily transferred to the launch area when needed. The United States would have higher confi- would probably be observable. Others believe that the Soviets would not have to launch a dence at monitoring restrictions on the allow- mass A SAT attack in order to gain important able number of launch sites. Restriction on military advantages. They point out that in launch facilities would increase the time be- some limited war scenarios, destroying a very tween A SAT launches and decrease the prob- small number of critical satellites could have ability of sudden, multiple kills. A combina- Therefore, there might tion of restrictions on both the allowable grave consequences. number of launch sites and on the number of not be a need for a large number of observable, pre-mated A SAT weapons and launchers. ASAT weapons that could be stored at each site could reduce the likelihood of a surprise Assuming the United States did have ad- attack or, at minimum, reduce the effect of vance notice of Soviet A SAT activities, it such an attack. could respond through diplomatic channels or through a Standing Consultative Committee, if established. Even short-term notice of intent Utility of Limitations on Possession to use A SAT weapons would allow the United and Deployment States time to maneuver its satellites or take other appropriate action. A comprehensive ban on ASAT possession and deployment is complicated by: 1 ) the ex- The fact that every element of an agreement istence of the Soviet, and, in the near future, cannot be monitored with high confidence does not necessarily mean it has no value. It is extremely difficult to monitor the “no nuclear The U.S. ASAT weapon currentl~ under dmrelopment is quite small, I~owe~.er, the %y’iet monitoring task is easier becau S[J weapons in space’ provision of the Outer the U.S. AS.AT weapon requires large and ciistincti~e support Space Treaty and yet the United States con- equipment and becaus(~ significant expenditures for milit ar~r tinues to adhere to it. Presumably, this is be- facilities, personnel. and weapons procurement would be re- vealed in the annual authorization and appropriate ion proces< cause the benefits of the treaty outweigh the of Congress or by the popular press. risk posed by potential Soviet cheating. 114 —

Even if a ban on possession and deployment some inherent ASAT capability would still be could not be monitored with high confidence useful in as much as it would reduce the threat it would, at minimum, oblige the Soviets to of the most highly capable and destabilizing conduct future A SAT weapons tests covertly. future ASATS systems. Nonetheless, a ban on This would complicate maintenance of the the possession and deployment of ASAT sys- current system, make upgrades difficult and tems would probably be most valuable if ac- advanced ASAT development less likely. The companied by a prohibition against the test- combination of these effects would make U.S. ing of non-ASAT systems in an A SAT mode. satellite survivability programs more effective The 1983 Soviet draft treaty contained an and might discourage the use of ASAT example of a comprehensive ban on posses- weapons. sion. Article 2(4) of the draft treaty would have Space systems with inherent rather than in- required that parties undertake, “Not to test tentional ASAT capabilities would be difficult or create new anti-satellite systems and to de- to restrict by a comprehensive ban on posses- stroy any anti-satellite systems that they may sion or deployment. Nonetheless, such sys- already have. ” Given the past statements of tems pose only a modest threat to critical U.S. Soviet officials and the draft treaties proposed assets. Those systems which employ nuclear by the Soviet Union, it is likely that the warheads (e.g., ICBMS, SLBMS, ABMs) might Soviets would be willing to negotiate a com- only be used in a terrestrial nuclear war or at prehensive ban on possession. It is less clear the risk of precipitating one. They would also whether they would be willing to negotiate risk damage to the attacker’s own satellites. some form of limited ban. If their primary con- Future maneuverable spacecraft, although ca- cern is protecting all of their space assets, then pable of some limited ASAT activity, would a limited ban might not be acceptable. If, on not be able to provide the rapid, multiple-kill the other hand, their purpose in negotiating capability likely to be obtained from future any ban is to limit the development of more dedicated ASAT systems, and are therefore effective ASATS or spacebased BMD technol- a considerably lesser threat. ogies, then there might be some partial bans that they would find acceptable. A regime which banned only deliberate ASAT systems and disregarded systems with

PROVISIONS RESTRICTING ASAT USE

Perhaps the least complicated ASAT agree- satellite attack as an unambiguous warning ment would be one that prohibited hostile acts of further aggressive intent. against satellites. Such an agreement would probably not attempt to limit specific ASAT Although a “no use” agreement might not systems, but would instead prohibit the use substantially reduce the threat of ASAT at- of all ASAT capabilities. Although a “no use’ tack, it could serve as a useful component of agreement could not strictly be considered other, broader arms control agreements. The “arms control, ” in as much as both parties definition of prohibited acts that might rea- would be free to develop and deploy any num- sonably result from the negotiation of a “no ber and kind of advanced ASAT system, it use’ agreement could lead to a clearer under- might usefully define what constituted a “hos- standing of the systems capable of perform- tile act” against a satellite. This agreed defi- ing those acts. This, in turn, might assist in nition of “hostile act” might serve to avoid the negotiation of agreements that prohibited some future conflict brought about by a con- the testing, possession, or deployment of fusion of intentions. It would also establish a ASAT weapons. 115

Monitoring Compliance With assets. Should nations eventually possess a “No Use” Agreement directed-energy weapons or space mines with an instantaneous and multiple kill capability, Compliance with a “no-use” agreement there will be significant advantages to being would be relatively easy to monitor. This is a first user of these weapons. Nations may find particularly true for the current generation of themselves in the position of having to use or ASAT weapons. The monitoring task would lose their offensive space-based assets. If the become slightly more difficult if the Soviets measure of effectiveness of a “no use” agree- were to follow the U.S. example and develop ment is how well it protects U.S. satellites in an air-launched interceptor. This would allow an otherwise unconstrained environment, then them to launch an ASAT attack outside of the one would have to conclude such an agreement Soviet Union-perhaps even from the western was of limited value. hemisphere if the appropriate facilities were installed in Cuba. Although the U.N. Charter and the Outer Space Treaty both implicitly prohibit hostile If it were possible to covertly develop acts against the satellites of other countries, ground-based directed-energy facilities or there may be some value to obtaining a for- more flexible air-based facilities, these might mal agreement that such hostile interference be used to damage the sensors of a U.S. satel- is a violation of international law and poten- lite in such a manner as to mimic an equipment tially a cause of war. A “no use” ASAT treaty malfunction. This is particularly true when the would, like the Geneva protocol on use of poi- object of an attack is not to destroy the satel- sonous gases, establish more clearly the “law lite, but rather to “blind” or “dazzle” delicate of civilized nations. ” Codifying what is already sensors. implicit in international law might serve to in- On the other hand, the effective use of on- hibit the willingness of nations to attack sat- board monitoring equipment could substan- ellites in a crisis before hostilities have bro- tially reduce this threat. To a limited degree, ken out on Earth and perhaps even for some satellites now have some on-board “state-of- period of low intensity conflict. health” monitoring equipment. It is possible Although a “no use” agreement would not, in to augment these sensors to determine whether itself, substantially reduce the risk or the effect a failure is due to an internal flaw or whether of an ASAT attack, it would serve as a useful it has been externally induced. These sensors addition to other, more comprehensive, ASAT might, for example, measure incident laser limitations. For example, an agreement that light, rises in temperature, or sudden acceler- restricted ASAT testing would benefit from ations. The inclusion of “stateof-health’ mon- the clear statement that hostile acts against itoring equipment on satellites combined with satellites were forbidden. Such an agreement a future spacebased surveillance system could would assist in developing the principle that provide the necessary ingredients to verify a the goal of ASAT limitations was to protect “no use” treaty with high confidence. space assets and to keep space from becom- ing an area of unrestrained conflict and not Utility of a “No Use” Agreement simply to control the development of one or another class of offensive weapons. In order to judge the utility of a “no use” agreement it is first necessary to understand It is likely that some type of “no use” agree what such an agreement could and could not ment would be acceptable to the Soviet Un- accomplish. Even if a “no use” agreement ion. It would, of course, be necessary to clearly could be monitored with very high confidence, define what constituted “use” under the agree in an environment of unconstrained ASAT de ment. In their 1983 draft treaty, the Soviets velopment, a “no use” treaty might make only defined “use” as meaning “to destroy, dam- a small contribution to protecting U.S. space age, disturb the normal functioning or change 116

the flight trajectory. ” Although the United viet draft except the phrase “disturb the States might agree in principle with the intent normal functioning” is replaced by “render in- of such a provision, it is unlikely that it would operable. ” The UCS language is, from a U.S. accept this exact language. The Soviet phrase perspective, probably more acceptable, since “disturb the normal functioning” might be it would seem to cover only actions that harm interpreted as prohibiting the use of electronic the satellite and not those that make its job countermeasures, and this interpretation harder. In the absence of formal negotiations, would probably be unacceptable to the United it is impossible to assess Soviet intentions or States. willingness to compromise on this point. The 1983 draft treaty of the Union of Con- cerned Scientists (UCS) is similar to the So-

PROVISIONS RESTRICTING SPACECRAFT OPERATION AND ORBITS

Whether or not the United States and the lished the rule of international conduct on the Soviet Union agree to restrict ASAT weapons high seas and provided the basis for the 1972 or capabilities it might be useful to negotiate Soviet-U.S. treaty on the “Prevention of In- a set of “rules of the road” for military space cidents On and Over the High Seas.”8 In this operations. These rules could serve the gen- latter agreement, the United States and the eral purpose of reducing confusion and en- Soviet Union established more specific rules couraging the orderly use of space, or they for the operation of their respective warships. could be designed specifically to aid in the de- In the civilian communications field, nations fense of space assets. Examples of general have agreed to work with the International rules might include agreed limits on minimum Telecommunication Union (ITU) to develop separation distance between satellites or re- rules to insure orderly use of the geostation- strictions on very low-orbit overflight by ary orbit and the radiofrequency spectrum. manned or unmanned spacecraft. These gen- Those nations possessing military satellites eral rules might also be used to establish new, might wish to establish an organization, or stringent requirements for advance notice of more limited working groups, to develop sim- launch activities. Specific rules for space de- ilar technical rules of conduct for military fense might include declared and possibly space activities. defended “keep-out zones, ” grants or restrictions on the rights of inspection, and limita- The Chicago Convention of 1945 established tions on high-velocity fly-bys or trailing. It the fundamental principle of state sovereignty might also be desirable to establish a means over territorial airspace. g The 1967 Outer by which to obtain timely information and con- Space Treaty established the equally impor- sult concerning ambiguous or threatening tant principle that space should be freely avail- activities. able for the use and exploitation of all nations.’” Since the beginning of the space age, Precedents can be found for each of the gen- nations have wrestled with, but failed to re- eral rules suggested above. The clearest example of international acceptance of “rules of the 6 road” is the 1960 multilateral agreement on 23 U.S.T. 1168; T. I.A.S. 7379. “’Convention on International Civil Aviation” (Chicago 1947), “International Regulations for Preventing 61 Stat. 1180, 15 U. N.T.S. 295, T. I.A.S. 1591 Collisions at Sea. ”7 This agreement estab- ‘“’’ Treaty on Principles Governing the Activities of States “ in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies, Jan. 27, 1967 (Article I) 18 U.S.T. 733 U.S.C. 1051: T. I.A.S. 5813 2410, T. I.A.S. 6347. 117 —

solve the question of how to characterize the International law recognizes that the con- boundary between airspace and outer space. ” cept of sovereignty extends to more than a na- As one author has observed, the very impor- tion’s land mass. For example, a country’s ter- tant difference between these two regimes is ritorial waters and contiguous airspace are that “states shoot at aircraft not authorized considered to be sovereign and defendable ele- to be in their airspace; they do not shoot at ments of that country. Extrapolating from satellites passing over that airspace. “12 This this concept, one method for protecting sat- distinction will become increasingly harder to ellites would be to negotiate or declare “keep- make as maneuverable space vehicles become out zones” around the most critical space as- more capable. Will nations continue to allow sets. The agreement or declaration of these overflight of their territory by military space- “keep-out zones” might also include the right craft which are also capable of aerodynamic to defend these zones once declared. Precedent flight? Practical and internationally consist- for the concept of “keep-out zones” can be ent “rules of the road’ may be necessary to found in the history of the SALT negotiations resolve this problem. pertaining to submarines. During the course of these negotiations a number of proposals Article IV of the “Convention on Registra- were discussed such as, ‘‘nesubmarine zones’ tion of Objects Launched into Outer Space” which would have prohibited missile-carrying currently requires signatories to supply the submarines from operating in certain parts of Secretary-General of the U.N. with informa- the ocean, and “no-ASW zones” (anti-sub- tion concerning its space objects and launches. marine warfare) that would have allowed the However, since the Convention requires only unhindered operation of submarines in select that the signatories supply this information areas to ensure that reliable retaliatory forces “as soon as practicable, ” it is of little use in would exist to deter a possible first strike. clarifying ambiguous activities in a timely manner. Article 4 of the “Agreement on Meas- ures to Reduce the Risk of Outbreak of Nu- clear War Between the United States of Amer- ica and the Union of Soviet Socialist Republics” also requires that “each Party . . . notify the other Party in advance of any planned missile launches if such launches will extend beyond its national territory in the direction of the other Party. ” Unfortunately, since this article does not apply to space launch vehicles it is of little use as a means to protect space assets. As space launches become more numerous and varied, an agreement providing for timely notification of launch and information on the characteristics of the vehicle may be essential to avoid crisis through confusion.

“This question has been considered almost annually in the U.N. Committee on the Peaceful Uses of Outer Space but has Photo credit Nat/onal Aeronautics and Space Adm/n/strat/on yet to be resolved. The position of the United States has been that such a delimitation has not been necessary and, indeed, Artist’s conception of the U.S. Space Shuttle servicing might impede beneficial space activities. a Space Station. As commercial and scientific space ‘z’’ Anti-Satellite Weapons, Arms Control Options, and the activities increase, internationally accepted “rules of Military Use of Space, ” William J. Durch, U.S. Arms Control the road” may be necessary to ensure that both military and Disarmament Agency, contract No. AC3PC103, July 1984, and nonmiIitary space activities are conducted i n a safe p. 3. and orderly manner. 118 —

Negotiated or declared “keep-out zones” and not just activities which create a risk of would have to be reconciled with Article II of nuclear war. the 1967 Outer Space Treaty which states, “outer Space . . . is not subject to national ap- Monitoring Compliance With propriation by claim of sovereignty, by means a “Rules of the Road” Agreement of use or occupation, or by any other means. “Keep-out zones” might be considered by The ability to monitor individual “rules of some nations to be contrary to the Outer the road” with high confidence would vary Space Treaty’s ban on “national appropria- directly with the specific measures adopted. tion. ” A counter argument might hold that As a general rule, however, monitoring “rules current international practice with respect to of the road” would be easier than monitoring communication satellites in geosynchronous other “arms control” regimes. The primary orbit already incorporates a variation of the purpose of such rules would not be to restrict “keep-out zone” principle. Current geosyn- substantially the activities of the parties, but chronous orbit must be space several degrees rather, to make the intentions behind these apart in order to avoid frequency interference. activities more transparent. Although the de- Therefore, such a satellite precludes the place- gree of protection for U.S. space assets to be ment of other satellites near its position in the gained from a “rules of the road” agreement orbital arc. would be less than from other arms limitation regimes, the costs are also correspondingly In order to reduce uncertainty regarding the less for failure to completely verify compli- purpose of certain satellites and the tension ance. One must assume that in the absence of likely to result from unauthorized close ap- ASAT arms control, both ASAT development proach, it might be useful to establish rules and satellite survivability programs will be regarding inspection, high-velocity fly-by and given high priority. This being the case, offen- trailing. Such agreements might allow close- sive and defensive measures would be avail- approach and inspection under certain circum- able to respond to violations of “rules of the stances (e.g., prior consent) but might other- road. wise ban high-velocity fly-by and trailing— either of which could be a prelude to satellite Utility of a “Rules of the Road” attack. Agreement One of the functions of a regime of rules in The “rules of the road” discussed above– space would be to reduce instances where if implemented in the absence of restrictions provocative or threatening activities are ob- on ASAT weapon development—would not re- served but not explained. To resolve this prob- move the threat of ASAT attack. If they were lem, a forum or a “hot line” might be estab- defended, “keep-out zones” would probably of- lished through which questionable space fer the closest thing to security in such a re- activities could be discussed in a timely man- gime. Space mines designed to shadow satel- ner. Precedent exists for this in the 1971 lites and detonate on command would lose a “Agreement on Measures to Reduce the Risk great deal of their utility if held at bay by a of Outbreak of Nuclear War, which requires defended keep-out zone. If these zones were the United States and the Soviet Union to sufficiently large, or if satellites were appro- notify each other “in the event of signs of in- priately shielded, they might even be effective terference with [early warning systems] or against nuclear space mines. Keep-out zones with related communication facilities, if such would be less effective against advanced occurrences could create a risk of outbreak of directed-energy weapons with kill radii of nuclear war. ” The 1971 agreement might be thousands of kilometers. However, these strengthened to require consultation regard- might be controlled by other arms control ing activities that might threaten satellites measures. 119 . — — —

‘‘Keep-out zones” combined with defensive space assets. Some rules, such as very low- satellites (DSATS) would offer substantial— orbit overflight by manned, reusable vehicles, though still incomplete–protection but would may be so politically sensitive as to not be likely be extremely expensive. As an alterna- amenable to discussion. Other rules, such as tive to defended “keep-out” zones, the United “keep-out zones” and minimum separation States might wish to develop redundant sys- distance for satellites, may not be desirable be tems and an ability to rapidly reconstitute lost cause they are not technically possible at al- assets. titudes where the majority of current U.S. and Soviet satellites are located. On the other “Rules of the road” would be substantially hand, some rules, such as high-velocity fly-by, more effective at encouraging the orderly use or close inspection might lend themselves to of space by the military and at reducing the discussion and agreement. chances of escalation or misunderstanding in a crisis. Even in the absence of controls on The United States and the Soviet Union ASAT weapons it would be valuable to have may wish to adopt “rules of the road” as a a multinational consensus concerning ambig- result of their increased use of space for mili- uous activities such as close-approach, very tary-including ASAT—purposes, or because low-orbit overpass, and high-velocity fly-by. they are engaged in negotiations designed to If the “rules of the road” were part of other limit the arms race in space. “Rules of the limitations on ASAT weapons and capabilities road” might be an attractive companion agree they would likely contribute to the effective- ment to far-reaching limits on A SAT weapon ness of these agreements and make their im- development. On the other hand, in the total plementation more manageable. absence of ASAT weapon limitations, there would be a need to clarify ambiguous activi- Whether “rules of the road” were negotia- ties before it became necessary to “use or lose’ ble would depend on the specific provisions offensive space weapons. The negotiability-or chosen. The negotiations pertaining to such lack thereof–of “rules of the road” can only rules might require the United States, the So- be discovered as a result of serious negotia- viet Union, and perhaps others, to sit down tion between interested parties. and discuss secret and extraordinarily sensitive issues relating to the operation of military

BMD AND ASAT TREATIES OF LIMITED DURATION

Each of the regimes examined above could allow parties to take advantage of future tech- be negotiated as a treaty of indefinite or nological options, yet can encourage aggres- limited duration or, alternatively, as one which sive development programs designed to reach remains in force as long as periodic reviews fruition at the termination of the designated are favorable. Each of these alternatives has period. Treaties which call for a periodic reas- its advantages and disadvantages. Treaties of sessment of agreed limitations in theory have indefinite duration are more effective at dis- great flexibility, yet, in practice, often result couraging the pursuit of banned activities, yet in a strong presumption that they should be require a greater degree of foresight regard- continued. ing the long-term interests of the signatories and can foreclose technological options for the indefinite future. 13 Treaties of limited duration preme national interest clauses, ” treaties may also contain specific unilateral or agreed statements regarding specific . understandings about related events. For example, The 1972 ‘Treaties of unlimited duration usually contain a clause which ABM Treaty contains a unilateral statement by the United allows the signatories to withdraw from the treaty if their “su- States which links the continued viability of the treaty to “more preme national interests” are threatened. In addition to ‘‘su- complete limitations on strategic arms. ” 120

The United States might, for example, en- tion continues to be in their national security ter into a treaty limiting ASATS with the ex- interest. plicit and public reservation that we would withdraw from this treaty if and when we were The Reagan Administration has recently in- ready to test and deploy a ballistic missile dedicated that it intends to conduct ASAT tests fense system in ways that the ASAT Treaty to gather information useful in advanced would forbid. Alternatively, we might take the BMD research. ” Given the close connection public position that we intended to restrict our between these two technologies, an ASAT BMD activities so as to remain within the treaty of even limited duration would require limits of an ASAT Treaty. While the former modification of current SD I program plans. position would suggest a treaty of limited du- Thus, to the extent that the United States ration and the latter a treaty of unlimited du- wishes to maintain the most rapid pace of ad- ration, this need not be the case. It would be vanced BMD research within the bounds of perfectly possible to sign a treaty of unlimited the ABM Treaty, such a treaty would not be duration, with the standard provision allow- desirable. Conversely, to the extent that the ing for withdrawal, accompanied by a clear United States wishes to slow the pace of So- statement of some of the conditions under viet BMD research and is willing to defer de- which we intended to withdraw. cisions regarding the testing of space-based or space-directed weapons, an ASAT treaty of From one point of view, the exact language limited duration could contribute to that in a treaty regarding its duration is less im- result. portant than the intentions of the parties. Af- ter all, there have been numerous examples of —. treaties of unlimited duration that were vio- “The purpose of tests “in an ASAT mode” would be to in- lated soon after they were signed and exam- vestigate advanced technologies without violating the ABM Treaty. The Department of Defense recently told Congress that, ples of treaties of limited duration that con- ‘{To ensure compliance with the ABM Treaty the performance tinued in force after they had expired (e.g., the of the demonstration hardware will be limited to the satellite “Interim Offensive Agreement” signed at defense mission. Intercepts of certain orbital targets simulating anti-satellite weapons can clearly be compatible with this SALT I). The real issue is whether the parties criteria. “ “Report to the Congress on the Strategic Defense Ini- believe that adherence to the treaty in ques- tiative, ” Department of Defense, 1985, app. B, p. 8.

COMPLIANCE MONITORING, VERIFICATION, AND RECOURSE

Verification of compliance with an arms con- Monitoring trol treaty provision involves three distinct processes: monitoring the activities of other When discussing the ability of the United parties to the treaty, interpretation of the States to monitor Soviet treaty compliance, information obtained by monitoring, and, it is important to distinguish existing and planned-capabilities from potential capabil- assessment of the risk which such activities pose to U.S. security. Each of these processes ities. Existing and planned monitoring capa- presents a different set of problems and op- bilities are described in chapter 4. Some of the portunities to the intelligence community. existing systems used to monitor compliance with SALT and other arms control agreements Should violations or potential violations of would be useful for monitoring compliance treaty obligations be discovered during the 6 with possible ASAT arms control provisions.1 verification process, then it becomes necessary — to decide what, if any, action is to be taken “Some of these capabilities have been described in general terms by Congressman Les Aspin in “The Verification of the in response. Verification of compliance and re- SALT II Agreement,” Scientifi-c Amen”can, vol. 240, No. 3, Feb course are discussed in greater detail below. ruary 1979, pp. 38-45. 121

For example, capabilities to monitor the con- and changing its pointing direction quickly— struction and dismantling of ICBM launchers as a prohibited weapon system might—or –the number of which is constrained by the whether, instead, it was only capable of reflect- SALT II agreement-could also be used to ing low-intensity radiation and changing its monitor the construction and dismantling of pointing direction slowly, as communication launchers for boosters used for ASAT weapons. system or telescope components might. 16 The ability to make such a determination would By investing in new monitoring systems and depend both on the sophistication of the mon- personnel, future monitoring capabilities can itoring system employed and prior knowledge be made more comprehensive than existing ca- regarding similar activities. pabilities. To a limited extent, one can actually ‘‘buy’ more monitoring capability. (See Even if the monitoring system provides data table 6-l). However, such additional capabil- sufficient to clearly identify the nature of a ities would, in most cases, require years of questioned activity, it still remains to be de- work and substantial expenditures of funds. termined whether that activity is prohibited As in weapon system procurement, it will be by the language of the relevant treaty. In the necessary to judge “how much is enough”- example of a mirror deployed in space, there i.e., to determine the level of investment above would remain the question of whether deploy- which the value of monitoring capability im- ment in space of any large mirror capable of provement obtainable per dollar ceases to be reflecting intense laser beams would be a vio- worth a dollar. lation. Since similar mirrors have been proposed for peaceful purposes (e.g., propulsion The fact that future monitoring systems 7 of laser-powered rockets1 ), even if the relevant could be more capable than current systems agreement defined weapons in terms of their does not mean that all monitoring problems capabilities rather than intended uses, there can be solved by spending more money on could be ambiguity as to the legality of deploy- advanced technologies. Some activities will ing such mirrors. always be unmonitorable (e.g., some forms of underground testing), other dual-purpose ac- When ambiguities are foreseen, treaty lan- tivities (e.g., manned spaceflight) will often be guage can be worded to avoid them. However, difficult to characterize. Although future tech- history has demonstrated that it is extremely nologies will increase our ability to monitor the difficult to foresee all the significant ambi- activities of other countries, similar technol- guities that could arise in an arms control ogies may make the job of treaty verification agreement. more difficult. Specific examples of these problems are presented above in the discussions Assessment of specific treaty provisions. If monitoring data are interpreted to indi- Interpretation cate that an activity prohibited by a treaty (or possibly inadvertently allowed by ambiguity Once indications of a potentially prohibited of the treaty) is taking place (or about to take activity have been detected by monitoring sys- place), the risk which the activity poses to U.S. tems, the data must be further interpreted to security must be assessed. This assessment determine the intent of the activity and how must take into consideration at least three fac- the activity affects specific treaty agreements. tors: 1) the threat to U.S. national security For example, suppose that while a space- posed by the specific violation; 2) assuming the weapon ban is in effect, the deployment or construction of a large mirror is observed in space. loThe lmge deployable reflector (LDR) under development by In this case, the monitoring data might be NASA is an example of such a component. l~R.R. Berggren and G.E. Lenertz, ‘‘Feasibility of a 3@ Meter scrutinized to determine whether the mirror Space Based Laser Transmitter, ” NASA-CR-134903, 1975 was capable of reflecting intense laser beams [NTIS accession number N-761 1421]. 122

violation, the extent to which the relevant offensive measures might be pursued to hedge treaty still contributes to U.S. national secu- against breakout. The hardest questions are rity; and 3) the ability of the United States to those that arise somewhere between these two take actions which will prevent, mitigate, or examples. compensate for damage that might be caused ASAT arms control raises a number of ques- by the violation. The result of such an assess- tions common to all high-technology treaty re- ment will often imply the appropriate nature strictions. For example, if one party violates of the recourse to be pursued. a test ban on advanced directed-energy ASATS and then, when confronted with the Recourse violation, declares its intent not to repeat this Given the many different activities that violation, what is the appropriate response? ASAT arms control could restrict and the nu- Some would argue that the damage has been merous ways that such agreements could be done. One side has had the opportunity to ver- violated, it is difficult to make generalizations ify a technology which it may have been de- about how the United States might or should veloping covertly over a period of years. The respond. Faced with a clear violation of a ma- side which remained in compliance has lost not jor treaty provision that seriously jeopardized only the information it could have gotten from U.S. national security, the United States similar tests, but potentially, years of research would be wise to withdraw from the treaty in experience. Others might argue that limited question. If, on the other hand, the existence testing or minor ambiguities offer no real and of a violation was uncertain and it pertained enduring military advantage. only to a subsidiary portion of an otherwise Other responses to clear or uncertain treaty valuable treaty, then it might be appropriate violations include negotiating modifications to to seek consultation to resolve this particular the agreement or matching cheating with iden- activity while leaving the treaty otherwise in- tical or equivalent conduct. Negotiating modi- 18 tact. Alternatively, unilateral defensive coun- fications can be a long and contentious proc- termeasures or R&D on treaty compliant ess, particularly if the negotiations require one party to admit to treaty violations or ambiguous conduct. Given the differences between Wthers have argued that the mere fact that a treaty has been Soviet and U.S. force structure and technol- violated is as important as the national security impact of the violation. For example, Colin Gray writes: ogy base, matching cheating with identical The Soviet noncompliance issue is not important as a matter conduct is often not a useful alternative. For of ethics or because the sanctity of international legal norms must be upheld . . Nor is Soviet cheating primarily important example, the United States may not desire to in terms of military advantage and disadvantage . . (Tlhe great- build a Krasnoyarsk-style radar. On the other est danger . . . results from the loss of U.S. credibility. . . (W~ar is more likely to explode out of a mutual diplomatic miscalcula- hand, matching cheating with equivalent con- tion (than a military imbalance), That miscalculation could be duct (the so-called “parallel interpretation” rooted . in a Soviet lack of respect for the quality of determination in U.S. policy. alternative) runs counter to notion that a Cohn Gray, “Moscow is Cheating, $’ Fore&n Poficy, No. 56, fall treaty should have one common understand- 1984, pp. 141-152. ing which is accepted by both parties. Chapter 7 Comparative Evaluation of ASAT Policy Options Contents

Page Policy Overview ...... 125 ASAT Policy Choices ...... 125 Alternative Legal/Technical Regimes ...... 125 Regime I: Existing Constraints ...... 127 Legal Regime...... 127 Offensive Posture ...... 128 Defensive Posture ...... 128 Net Assessment...... 129 Regime 2: A Comprehensive Anti-Satellite and Space-Based Weapon Ban ...... 130 Legal Regime...... ,.....130 Offensive Posture ...... 131 Defensive Posture ...... ,131 Net Assessment...... 131 Regime 3: An ASAT Weapon Test Ban and Space-Based Weapon Deployment Ban ...... 132 Legal Regime...... 132 Offensive Posture ...... 132 Defensive Posture ...... 133 Net Assessment ...... 133 Regime4: “OneEach/NoNew Types’’ Regime...... 134 Legal Regime...... 134 Offensive Posture ...... 134 Defensive Posture ...... 135 Net Assessment...... 135 Regime 5: Rules of the Road ...... 136 Legal Regime...... 136 Offensive Posture ...... 138 Defensive Posture ...... 138 Net Assessment...... + ...... 138 Regime6: Space Sanctuaries...... 138 Legal Regime...... 138 Offensive Posture ...... 4...... 139 Defensive Posture ...... 139 Net Assessment...... 139 Regime 7: A Space-Based BMD Regime ...... 140 Legal Regime...... 140 Offensive Posture ...... 140 Defensive Posture ...... 140 Net Assessment...... 141

Table Table No. Page 7-1. Effect of Regimes on ASAT Development and Arms Control...... 126 .

Chapter 7 Comparative Evaluation of ASAT Policy Options

POLICY OVERVIEW ASAT Policy Choices limited number for analysis. These packages have been constructed so that each will have Over the next 5 years, the United States will at least one advantage over the others consid- have to make key decisions regarding research ered and so that each contains elements which and development programs for anti-satellite might reasonably be expected to coexist in the weapons and countermeasures and for ballis- same proposal. Consideration of these regimes tic missile defense (BMD) systems. In addi- is intended to facilitate assessment of the ef- tion, the United States must also consider fectiveness and desirability of different com- whether it wishes to seek agreement with the binations of ASAT and BMD technology de- Soviet Union to halt or limit the development velopment, satellite survivability, and arms of certain weapons that would operate from control. space or against space objects. This chapter The seven regimes considered in the remain- analyzes the relationships between offensive ] and defensive weapons programs and arms ing sections of this chapter are : control. In so doing, it utilizes the technology 1 Existing Constraints. The first regime is discussions contained in chapters 3 and 4 and defined by treaties and agreements pres- the discussions of arms control found in chap- ently in force. The ways in which this legal ters 5 and 6. regime would affect technology develop- As discussed in chapter 6, those regimes ments designed to protect U.S. satellites which require negotiated arms control agree- or to place Soviet satellites at risk will be ments could be either of limited or unlimited examined. duration. Opponents of developing BMD sys- 2. A Comprehensive Anti-Satellite and Space- tems might prefer an agreement of unlimited Based Weapon Ban. Regime two could be duration. Agreements of limited duration– established by adhering to treaties and perhaps 5-10 years—might be attractive to agreements presently in force and, in proponents of advanced BMD research if they addition, agreeing to forgo the possession could be fashioned so as not to interfere with of deliberate anti-satellite weapons, the plans to develop and test prototype BMD testing—on Earth or in space—of any weapons. Such agreements would have the ad- deliberate ASAT capability, the testing ded benefit of temporarily constraining the de- in an ‘‘ A SAT mode’ of systems with in- velopment or testing of advanced .ASAT weap- herent ASAT capabilities, and deploy- ons which could attack space-based BMD ment—on Earth or in space—of any system components. ASAT weapon. <.? An ASA’T Weapon Test Ban and a Space- Based Weapon Deployment Ban. The third Alternative Legal/Technical Regimes This chapter considers possible arms control ‘These reginles might usefully include elements not discusswi h(rc, ~70J” ex:jmp]t, r~~~jn]t,s ~, ,?, 4, and 5 might also include a provisions, ASAT postures, and counter-meas- “no-use” pro~ l~ion w hi(h would prohihit the parties from de- ures together as packages in order to exan~- st ro~ri ng or ‘‘ rend(’rirrg inoperah]e each others satellites. “resting in an “AS. A’I’ mode” would include tests of land-, ine their interaction. Since there are many con- vea , air-, or spacf~-has(wi s~’st(~nls agairlst targets in space or ceivable packages, it is necessary to select a a~rai ns t points in spa(YI

125 126 —

regime could be created by adhering to Table 7-1 .—Effect of Regimes on ASAT Development treaties and agreements presently in force and Arms Control —.———— and, in addition, agreeing to forgo test- Restrict with Develop ASAT ing in an “A SAT mode” and the deploy- arms control weapons ment of any weapon in space. This regime Existing constraints ... No Yes differs from regime 2 most importantly Comprehensive ASAT and space-based in that it would not ban possession or weapon ban . . . . Yes No testing–on Earth-of deliberate ASAT Test ban and space- weapons. based weapon ban . . . . Yes Yes/No a One each/no new types ., Yes Yesb 4. A “One Each/No New Types” Regime. Re- Rules of the road . . . . Yes Yesc gime 4 includes arms limitation provi- Space sanctuary ...... Yes YesC sions which would permit the United Ballistic missile defense . No Yes ain this regime ASAT weapons could be developed, tested, and dePloyed on Eaflh States and the Soviet Union to test and but not In space The United States could pursue ASAT development wlthln the bounds of the treaty, or (t could forego ASAT development entirely deploy their current ASATS but would bAll ASAT weapons other than “current types” could not be tested or deployed prohibit testing of more advanced sys- In space c Development and deployment opt !onal but strongly SU pported by advocates of tems. Advanced systems prohibited this regime would include those capable of operating or attacking targets at higher altitudes Ban and Space-Based Weapon Deployment and those that would be deployed in Ban, ” all other regimes assume some level of space. For the purposes of this assess- ASAT development. These regimes demon- ment, the U.S. MV will be considered to strate that although anti-ASAT arms control be the only deliberate “current” U.S. arguments and pro-ASAT weapon arguments ASAT. are related, there are many distinguishing fea- 5. Rules of the Road. The fifth regime illus- tures. ASAT arms control proponents believe trates the advantages and disadvantages that an ASAT treaty is in the national inter- of establishing ‘‘keep-out zones’ around est; those who support ASAT weapon devel- individual, high-value satellites. opment believe that this also is in the national 6, Space Sanctuaries. Regime 6 would pro- interest. However, ASAT arms control propo- vide high-altitude sanctuaries where sat- nents do not necessarily oppose all types of ellites could operate but where the test- ASAT development and ASAT weapon prop~ ing or deployment of weapons would be nents do not necessarily oppose all types of forbidden. ASAT arms control. ‘7. A Space-Based BMD Regime. The seventh regime might result from U.S. or Soviet Although the individual regimes vary con- withdrawal from the ABM Treaty fol- siderably, all of them should be assessed with lowed by the deployment of space-based two important considerations in mind: BMD systems. 1. First, if we wish to continue to use space As table 7-1 demonstrates, the regimes dis- for military purposes, a commitment to sat- cussed here can be characterized both by the ellite survivability is essential whether or extent to which they rely on negotiated arms not any arms limitation agreements are in controls and by the extent to which they al- force. The existence of space systems with low or encourage ASAT development. With some inherent A SAT capability makes it the exception of the “Existing Constraints” impossible to ban the ability to attack sat- and the “Space-Based BMD” regimes, all ellites. Therefore, even under the most re- other regimes involve some type of arms con- strictive ASAT arms control regime, pro- trol. With the exception of the “Comprehen- grams for satellite survivability and sive Anti-satellite and Space-Based Weapon countermeasures must be pursued. In the Ban, ” and perhaps, the “A SAT Weapon Test absence of arms control limitations on 127

ASATS, ensuring satellite survivability there will always be some risk that criti- will be a more demanding task. cal satellites can be destroyed or rendered 2. Second, the United States should exercise inoperable. The value of continued and fu- caution in its reliance on space assets to !per- ture reliance on space systems must be form tasks essential to the national secu- balanced against the probability that rity. No matter what arms control or sat- such assets may not be available in a con- ellite survivability measures are taken, flict situation.

REGIME 1: EXISTING CONSTRAINTS Legal Regime Space Treaty. The SALT and ABM Trea- ties also prohibit interference by either The United States could decide that there state with space assets used by the other are no additional arms control limitations re- to monitor those treaties. lating to space weapons that are in its national Placement of Nuclear Weapons in Orbit: security interest. If so, development of anti- Article IV of the 1967 Outer Space Treaty satellite and space-based weapons by the (OST) prohibits orbiting nuclear weapons. United States and the U.S.S.R. could continue This would include nuclear “space mines’ unrestrained except by the Limited Test Ban and, presumably, ASATS that used a nu- Treaty, the Outer Space Treaty, and the ABM clear explosion as a power source. Treaty.’ Detonation of Nuclear Weapons in Space: Even in the absence of new arms control The 1963 Limited Test Ban Treaty (LTBT) limitations there are restrictions on what the prohibits nuclear weapons tests or other United States and the Soviet Union can do in nuclear explosions in space. This would space. As discussed in chapter 5, under exist- prohibit the full testing of ASATS that ing international law and the treaties to which use nuclear explosions for destruction or the United States is a party, the following as a power source. activities are already banned: Development, Testing, or Deployment of Weapons Capable of Countering Strategic ● Unprovoked Attack on Another Country’s Ballistic Missiles, or Their Elements in Satellite: Subject to the right of individ- Flight: Space-based weapons sophisti- ual or collective self-defense, Article 2 of cated enough to “counter strategic ballis- the U.N. Charter prohibits the use or tic missiles or their elements in fLight” are threat of force. A similar sentiment is to banned under the terms of the 1972 ABM be found in Article III of the 1967 Outer Treaty. This establishes a somewhat ——. . vague upper limit on the capabilities of ‘The unratified Threshold Test Ban Treaty, and the unrati- advanced ASAT weapons. fied SAI,T 11 Treaty, if adhered to, would supply additional restrictions. The Threshold Test Ban Treaty, which was signed To summarize, the existing international le- in 1974, prohibits testing orI Earth of nuclear weapons with a gal regime prohibits the use of ASAT capa- yield greater than 150 kilotons. Should a nuclear ASAT weapon require a nuclear explosive of greater yield than this, it could bility except in national or collective self- not be fully tested without violating the Threshold Test Ban defense, the testing or deployment of space- Treaty. Under Article IX of the Salt II Treaty, the parties based weapons with strategic BMD capabil- agreed not to develop, test, or deploy “systems for placing into Earth orbit nuclear weapons. ” This might be interpreted to in- ity, and the testing in space or deployment in clude nuclear A SAT weapons. orbit of nuclear space mines or ASATS that 128

would require a nuclear detonation as a power ● Space-Based Lasers: Nonnuclear, space- source. The existing regime places few restric- based lasers are allowable. tions on the current ASAT research and de- ● Space-Based Neutral Particle Beam Weap- velopment programs of either the United ons: There are no restrictions on space- States or the Soviet Union. based neutral particle beam weapons. ● Maneuverable Spacecraft: Although not Offensive Posture necessarily “deliberate” ASAT systems, maneuverable spacecraft could be given In the absence of further restrictions, the fol- substantial A SAT capabilities under the lowing weapons could be developed, tested, existing regime. and deployed as deliberate ASAT weapons by either the United States or the Soviet Union, In addition to these deliberate ASAT sys- if deployed in compliance with the ABM tems, other weapon systems such as ICBMS Treaty (i.e., so as not to be capable of coun- or ABMs that have some ASAT capability tering strategic ballistic missiles or their ele- could be developed and deployed, but could ments in flight)4: not be completely tested as ASAT weapons. Such systems could be tested in space as long ● Coorbital Interceptors: Ground-launched, as they were not detonated. The SALT agree- nonnuclear coorbital interceptors—e.g., ments and the ABM Treaty do place other re- the current Soviet ASAT–are allowable strictions on ICBMS and ABMs. under the existing regime. Ground-based nuclear systems could be developed and Defensive Posture deployed but not tested in space. There are no restrictions on nonnuclear coorbi- The United States and the Soviet Union tal interceptors predeployed as space could develop, test, deploy, and use defensive mines. measures such as hiding, deception, evasion, ● Direct-Ascent Interceptors: Ground- hardening, and proliferation without legal re- launched or air-launched direct-ascent in- straint in the existing regime. In addition to terceptors–e.g., the U.S. ASAT being such passive countermeasures, nondestructive developed–are allowable. Direct-ascent active countermeasures such as electronic interceptors carrying nuclear weapons countermeasures (ECM) and electro-optical could be developed and deployed but not countermeasures (E-OCM) could also be used. tested in space. ECM and E-OCM are likely to be available and ● Ground-Based or Airborne Lasers: There inexpensive and are unlikely to by restricted are no restrictions on nuclear or nonnu- by arms control agreements; however, these clear ground based lasers, or on airborne countermeasures could be defeated at a rea- lasers that would not require a nuclear ex- sonable cost. plosion in the atmosphere. ✍ ——— Many destructive active countermeasures ‘The constraint that ASAT weapons not be deployed so as would also be allowed under the present re- to be capable of countering strategic ballistic missiles or their gime. Satellites could be given a self-defense elements in fight is restrictive, but several deployment schemes can be conceived which would be both lawful and useful. For capability (shoot-back) or provided with an es- example, a neutral particle beam weapon of relatively low power cort defense (DSAT). The current ASAT in- might be deployed in geosynchronous orbit for ASAT or DSAT terceptors being developed by the United purposes. It might be capable of damaging an enemy satellite or ASAT several hundred kilometers away within several States and the Soviet Union (respectively, the seconds, but incapable of darnaging a distant ballistic missile U.S. Air Force Miniature Vehicle and Soviet during its flight time of a few minutes. Deployment of such coorbital interceptor) are not capable of attack- weapons might also be allowed in low orbit, if the U.S.-Soviet Standing Consultative Commission-which was established by ing each other. However, many advanced the ABM Treaty to consider allegations of treaty violations— ASAT weapons that could be built in the cur- should agree that such weapons, if never tested as BMD sys- rent regime would have some effectiveness tems, could not reasonably be expected to have a significant BMD capability. against some types of ASATS. For example, 129

a space-based neutral particle beam weapon, ments, if any, or for targeting future ASAT in addition to its ASAT role, could also be used (or DSAT) weapons, if any. as a DSAT to provide ‘enclave defense’ ‘—i.e., to defend a number of distant satellites from Net Assessment other weapons such as coorbital or direct- ascent interceptors or continuous-wave lasers. Treaties and agreements presently in force However, neutral particle beam weapons de- create no significant barrier to the develop- ployed as DSATS could not shoot back effec- ment, testing, and deployment of very capa- 5 tively at larger neutral particle beam ASATS, ble, nonnuclear ASAT weapons. The current nor could they shoot back effectively at ex- regime also allows a wide range of active and pendable single-pulse weapons such as pre- passive countermeasures, including the de- deployed nuclear “space mines” or some nu- velopment of satellites capable of defending clear or nonnuclear directed-energy weapons. themselves by striking at attacking ASAT weapons. Moreover, if shoot-back is to be effective, space objects with known or suspected A SAT The primary advantage of the current re- capabilities would have to be fired upon while gime is that it allows the almost unrestrained still some distance from U.S. satellites be- application of U.S. technology to the related lieved to be in danger. As discussed above, at- problems of protecting U.S. satellites and plac- tacking an approaching spacecraft is pro- ing threatening Soviet satellites at risk. Un- hibited by international law except in self- der this regime, the United States would be defense and one could not be certain that the free to use its comparative advantage in ad- approaching spacecraft had a hostile intent vancecl technology to keep pace with expected until it was too late. Hence, active defense developments in Soviet ASATS and other mil- against suspected “space mines” might be itary satellites. Advanced U.S. ASATS might considered to be unlawful in the existing re- discourage the development of more capable gime, although deployment of means for such Soviet military satellites designed to place defense may not be. U.S. terrestrial assets at risk. In addition, the United States would be free to respond to So- Neither passive nor active countermeasures viet ASAT weapons with increasingly sophis- could guarantee the survival of satellites at- ticated defensive weapons and countermeas- tacked by some advanced directed-energy ures, thereby reducing the probability tl-iat the weapons. Although, as discussed in chapter Soviets could successfully use their intentional 4, the cost of destroying small, inexpensive or inherent A SAT capabilities. Effective A SAT satellites and decoys with advanced directed- capability could also give the United States energy weapons might exceed the cost of a powerful countermeasure against potential building such satellites and decoys. Security Soviet space-based BMD systems. for large and expensive satellites might ultimately have to rely on an attempt to deter In addition, research and development on A SAT attacks by credibly threatening retali- new balfistic missile defense technologies can ation against enemy space-based or terrestrial also proceed without the constraints that assets. A credible retaliatory capability would might be imposed by certain ASAT arms con- require a means of discovering that U.S. sat- trol regimes. Testing of advanced ASATS ellites had been attacked and identifying the could provide valuable information that would attacker. This would probably require attack contribute to the development of very capa- sensors mounted on satellites and a space- ble BMD systems. Such testing in the “ASAT based surveillance system to track and distinguish ASATS from meteorites or space debris. 5ASAT weapons capable of operating in an “ABM mode’ are, The latter could also be used to verify com- or course, limited by the ABM treaty. See discussion, supra, pliance with future A SAT arms control agree- p. 127. mode” could allow some research to go for- of such satellites could be misinterpreted as ward that, if designated as BMD research, a sign of imminent attack, since potential nu- might be considered to be inhibited by the clear aggressors would find such satellites to ABM Treaty. be attractive targets.

The primary disadvantage of the current re- Another potentially destabilizing factor is gime is that it might lead to an expensive and that some satellites (particularly communica- potentially destabilizing arms race in space. tion satellites) play a dual role—they are in- Rather than protecting satellites, a competi- tended to be force multipliers in a conventional tion in space weapons might severely reduce war, yet they are to play a key role in manag- their military utility. Under conditions of un- ing a conflict so as to avoid unwarranted es- restrained competition, security might be pur- calation. In the event of a conventional war, chased only at the price of a substantial and the possessor of a capable ASAT system sustained commitment to the development of would have a strong incentive to attack sat- increasingly sophisticated offensive and defen- ellites that were providing support to conven- sive space weapons. In such an environment, tional enemy forces. Destruction of these sat- ensuring the survivability of satellites would ellites, however, might contribute to escalation require more than simple hardening or eva- from conventional to nuclear war. sion. Costly measures might have to be taken An unrestrained competition in ASAT such as the deployment of precision decoys, weapons would also increase the risk posed to pre-deployed spares, or the ability to quickly space-based ballistic missile defense systems. reconstitute ones space assets. Satellites ca- Such systems are likely to have many critical pable of defending themselves or a compan- assets based in low-Earth orbit. So situated, ion satellite might ~so have to be developed extensive precautions would have to be taken and deployed. to protect them from even modest ASAT Should space mines or directed-energy weap- weapons. ons be deployed, they might be capable of the It is possible that an ASAT weapon com- almost instantaneous destruction of a large petition could also inhibit the use of space for number of critical satellites and ASATS. This commercial and scientific purposes. Manned could force nations into a situation in which space stations would be quite vulnerable to they must “use or lose” their own pre-de- ASAT attack. Should considerable ASAT ployed space weapons. This might supply the testing take place, the resulting debris could incentive to escalate an otherwise manageable prove harmful to scientific and commercial crisis. If missile early warning and communi- satellites. cation satellites were highly vulnerable, crisis stability might be lessened. The malfunction

REGIME 2: A COMPREHENSIVE ANTI-SATELLITE AND SPACE- BASED WEAPON BAN Legal Regime bilities, and the deployment–on Earth or in space—of any ASAT weapon.6 In addition, the This regime could be established by adher- U.S.S.R. would be required to destroy all its ing to treaties and agreements presently in .—— force and, in addition, agreeing to forego the ‘iSuch an agreement might resemble the draft treaty proposed possession of deliberate anti-satellite weapons, to the United Nations by the U.S.S.R. in August of 1983, ex- the testing—on Earth or in space—of any de- cept the testing or use of manned spacecraft for military purposes would not, in general, be banned as proposed in Article liberate ASAT weapon, the testing in an “ASAT 2 of the 1983 Soviet draft treaty. (U.N. Document A/38/194, mode” of systems with inherent ASAT capa- Aug. 23, 1983). The fifth provision of Article 2 of this proposed 731 coorbital interceptors and the United States satellites in high-altitude orbits would enjoy would be required to destroy the direct-ascent a high degree of security in this regime. interceptor it is currently developing. Net Assessment

Offensive Posture Although this regime would contain the most far-reaching arms control provisions and In this regime, the United States could not therefore might be most effective at prevent- maintain any deliberate ASAT weapons, ing the development of new and more threat- whether dedicated or multi-role, nor would the ening ASAT weapons, it would have the dis- U.S.S.R. be allowed to do so. Space systems advantage of being the most difficult to verify. with inherent ASAT capabilities such as Unlike an ASAT Test/Space-based Weapon ICBMS, ABMs, and maneuverable spacecraft Deployment Ban (regime 3), a comprehensive would still be allowed, but they could not be ban would prohibit possession of ASAT weap- tested in an “A SAT mode. ” ons on Earth. Because it is difficult to obtain information about Soviet military affairs, the Defensive Posture United States would have to assume that the Soviet Union could possess some number of Under a comprehensive ASAT ban the United their current ASAT weapon. States would retain the right to deploy and use passive countermeasures such as hiding, de- The current Soviet coorbital interceptor is ception, evasion, hardening, and proliferation. a relatively small spacecraft launched on much The United States would not be allowed to de- larger, general-purpose boosters. Maintaining velop, possess, test, or deploy weapons for sat- such boosters and their launchpads would be ellite self-defense, defensive satellites (DSATS), allowed, and it would have to be assumed that or other systems intended to have anti-sat- the U.S.S.R. would continue such activities. ellite capabilities, even for defensive purposes. Construction of additional boosters and launchpads would also be allowed by an ASAT ban If the U.S.S.R. complied fully with the let- of the type considered here. Hence the U.S.S.R. ter of such a comprehensive ASAT ban, the could maintain and even expand its ASAT risk posed to U.S. satellites would be limited force with some confidence that the United to the risk posed by possible Soviet use of States could not gain unambiguous evidence ICBMS, SLBMS, ABM interceptors, and pos- of a violation of an A SAT possession ban. sible future highly maneuverable spacecraft. However, even if the U.S.S.R. maintained If U.S. satellites were hardened against the ef- some coorbital interceptors, it could not test fects of nuclear explosions to a modest degree, them without risking almost certain detection, only low-altitude U.S. satellites would be at and in time the confidence of Soviets in a long- significant risk of damage by such inherent untested and never perfected A SAT weapon ASAT capabilities, and then primarily at the might erode. nuclear level of conflict. Assuming Soviet compliance, U.S. warning and communications There would always be the possibility that the Soviets might develop a new type of A SAT —— weapon with the intention of using it, with- treaty would obligate parties “not to test or use manned space- out prior testing, in extremis (e.g., if anticipat- craft for military, including anti-satellite, purposes. ” If this pro- ing an imminent attack). For example, the vision were stricken or changed to read “not to test or use manned spacecraft for anti- satellite purposes, the resulting U.S.S.R. might equip an existing booster or draft treaty, if acceded to by the United States and the U. S. S. R., satellite vehicle with a nuclear explosive— would establish a regime of the type considered in this section. either an isotropic nuclear weapon or possibly The fifth provision of Article 2 of the proposed Soviet draft a nuclear directed-energy weapon—and main- treaty would obligate parties *’Not to test or create new anti- satellite systems and to destroy any anti-satellite systems the~ tain it in readiness for launch or actually may already have. launch it into space. The military utility of 132 such untested systems would be questionable, risk posed by possible illegal Soviet use of particularly if the United States aggressively ASAT weapons might be somewhat lower in pursued available satellites survivability a regime in which the Soviets could not law- measures. fully possess ASAT weapons. Presumably, the inability to overtly possess ASAT weapons Since the United States might agree to a would diminish one’s ability to use them ef- comprehensive ASAT ban only after consid- fectively. Furthermore, an absolute ban on erable political friction over question of com- possession might make it less likely that the pliance and verification, it would be important current generation of ASAT weapons could be to consider how such a ban might make a upgraded and held in readiness in significant greater contribution to U.S. national security numbers. than a ban on ASAT testing and space-based weapon deployment (regime 3). The purpose However, if the United States could only be of both bans would be to prevent the use of confident that the Soviets were complying ASATS, or, at minimum, to reduce the prob- with a treaty to the extent we could verify ability that an ASAT attack would be effec- compliance, then the United States would not tive. An ASAT test ban would primarily affect have confidence that this regime offered any weapons reliability, while an ASAT possession greater protection to our satellites than does ban, if observed, would affect both availabil- regime 3 (test ban and space-based weapons ity and reliability. It is conceivable that the ban).

REGIME 3: AN ASAT WEAPON TEST BAN AND SPACE-BASED WEAPON DEPLOYMENT BAN

Legal Regime exist and have inherent ASAT capabilities which pose some threat to satellites. It might This regime would ban what can be moni- be possible to increase the ASAT potential of tored with greater confidence—testing in an these systems without violating a ban on the “ASAT mode”7 and ASAT deployment in testing of ASAT weapons. In addition, upon space. Everything that is prohibited under the entry into force of a ban on ASAT testing, the current regime would continue to be prohib- United States and the U.S.S.R. would possess ited. In addition, further testing—in space— deliberate ASAT weapons which would have of the current Soviet coorbital interceptor and undergone some developmental testing, al- the U.S. direct-ascent interceptor would be though possibly not enough to perfect their prohibited, as would the placement of any designs. Such weapons could be maintained weapons in space. Unlike regime 2, this regime in partial readiness. However, without opera- would not attempt to ban testing, possession, tional testing for reliability evaluation and or deployment of ASAT weapons on Earth. training purposes, confidence in the effective ness of such weapons would probably degrade Offensive Posture in time. Although they could not be tested overtly Advanced ASAT weapons such as neutral in an “ASAT mode, ” a number of weapons particle beam weapons or x-ray lasers could which have some limited A SAT capability al- be developed and maintained in partial readi- ready exist or could be developed. ICBMS, ness, but could not be completely tested. Con- ABMs, and maneuverable spacecraft already fidence that such weapons would perform ade ———— .——— quately if used might be so low that one would ‘Testing in an “A SAT mode” would include tests of ground-, not rely on them in an aggressive first strike air-, sea-, or space-based systems against targets in space or against points in space. Testing on the ground of ASAT sys- nor find it cost-effective to develop them for tems or components would not be prohibited. that purpose. On the other hand, one might 133

use them, if attacked, to degrade enemy ca- inherent, in a test-ban regime, just as in the pabilities supported by satellites, and might existing regime. Destructive active counter- find it cost-effective to develop them for that measures, on the other hand, would be se- purpose. That is, the discrepancy between of- verely constrained: new ASAT weapons use- fense conservatism and defense conservatism ful as DSATS could be developed but could not might decrease the risk which untested weap- be tested nor deployed in space. An untested ons could pose if possessed by an aggressive NPB or XRL built and readied for quick nation. launch and use as a DSAT could not be responsive enough to use for defensive shoot-back Defensive Posture against expedient ASAT weapons such as ICBMS but might have value if maintained for In this regime, testing and deployment in retaliatory shoot-back. space of advanced ASAT weapons would be prohibited but might be attempted by the U.S.S.R. covertly or after a breakout.8 Hence Net Assessment the choice of passive countermeasures in this regime would be influenced by the same con- A negotiated ban on the testing of weapons siderations which favor deception and modest in space or against space objects would limit nuclear hardening in the existing regime. Such the nature and extent of U.S. and Soviet arms measures would be more effective, however, competition in space. Advanced ASAT di- in a test-ban regime because it could be as- rected-energy weapons which could threaten sumed that the ASAT threat would be reduced high-altitude satellites with prompt destruc- to some degree by the arms control provision. tion could not be lawfully tested and attempts Passive countermeasures would also be more to extensively test such weapons covertly important in this regime, because destructive would probably be detectable. Although such active security measures—e.g., shoot-back a ban could not eliminate all threats to satel- with reliable, tested DSAT weapons—would lites, it would substantially reduce the cost not be an option. Deep-space surveillance and complexity of ensuring a reasonable level would be even more desirable in this regime of satellite survivability. The United States than in the existing regime, because of the would still benefit from hardening its satellites need to monitor compliance as well as for its to some extent and deploying spares and de- role in providing attack assessment informa- coys, but the more elaborate, expensive, and tion. Hence, in a test-ban regime, attack sen- possibly ineffective precaution of developing sors, space-based LWIR sensors, satellite de- and deploying DSATS would be prohibited coys, and modest nuclear hardening would be and, indeed, less attractive. In the absence of at least as desirable, as in the existing regime, reliable, effective ASATS, satellites would be if not more so. of greater utility since the United States might have higher confidence that they would Nondestructive active countermeasures such be available when needed. as ECM and E-OCM would be desirable, if not Relative to the existing regime, the primary ‘Although deployment of an NPB in space—a prerequisite advantage of a regime banning testing of for testing-would probably be observable, maintaining an un- ASAT capabilities and deployment of space- tested NPB weapon on Earth in readiness for quick launch might not be, and would be allowed. Maintaining an untested based weapons would be that highly valued XRL weapon on Earth in readiness for quick launch might also U.S. satellites in higher orbits–e.g., the future be difficult to dekt and would also be allowed under the terms MILSTAR system–could be protected with of an ASAT test and SBW deployment ban. Illegal deployment of an untested XRL in space would be difficult and costly to some confidence from advanced A SAT weap- observe. However, an enemy could have little confidence in the ons, especially if protected as well by passive reliability and performance of untested NPB or XRL weapons, countermeasures. The fact that advanced so such weapons would not be as threatening as in the existing regime in which NPB weapons could be legally tested in ASATS could not be overtly tested would re- space. duce the probability that they would be devel- 134 oped and deployed. If they were developed and From the point of view of those interested used without prior or complete testing, the im- in preserving the present agreement beween probability of their success compounded with the United States and the Soviet Union limit- the improbability of their attacking an oper- ing ballistic missile defenses, another advan- ational satellite rather than a decoy (if such tage of an ASAT test ban would be its pre- are deployed) would afford such satellites convention of tests of ASAT technologies with siderable protection and would, at least, dis- potential BMD applications. proportionately increase an enemy’s cost for On the other hand, from the point of view an effective ASAT capability. In addition, a of those favoring intensive BMD research, a ban on testing advanced ASAT weapons and primary disadvantage of this regime, relative deploying them in space would plausibly in- to the existing regime, is that the testing of hibit future competition in developing space- some types of advanced BMD weapons might based weapons and would discourage devel- be prohibited. Such limitations could be opment and covert testing and deployment of slightly more restrictive than those of the ASAT weapons of types which would pose the ABM Treaty, and would be very restrictive strongest incentives for preemptive ASAT at- compared to a regime in which the ABM tack. These benefits might be deemed advan- Treaty was no longer in force [regime 7]. Fi- tageous by both the United States and the nally, it must be recognized that a ban on test- U.S.S.R. ing ASAT capabilities and deploying space- As in the existing regime, the United States based weapons would not offer absolute pro- could retain a capability to attempt to negate tection for satellites; there would remain some low-altitude Soviet satellites (e.g., RORSAT) possibility that an untested or partially tested with its MV ASAT in the event of war and to ASAT, if suddenly deployed and used, might respond in kind to a Soviet ASAT attack. actually work well enough to overcome pas- However, confidence in the operational capa- sive countermeasures. bility of this system might degrade over time without continued operational testing.

REGIME 4: A “ONE EACH/NO NEW TYPES” REGIME Legal Regime Offensive Posture A “one each/no new types” regime might be Offensive postures in a “no new types” re- established by adhering to agreements cur- gime would be as in an ASAT test ban and rently in force and further agreeing to ban the space-based weapon deployment ban regime deployment in orbit of any weapon and the (regime 3), except ASAT weapons of the sin- testing in space, “in an ASAT mode” of any gle allowed type would almost surely be main- system except the currently operational type tained for offensive ASAT missions in war- of Soviet coorbital interceptor and the U.S. time.’” It is possible that each side would be MV direct-ascent interceptor.g Research on ad- satisfied with the capabilities such fully tested vanced systems and testing of these systems weapons could provide and would be less on Earth would not be prohibited. tempted than it would be in a test ban regime to covertly develop advanced ASAT weapons. ‘Although the U.S. Department of Defense has stated its belief that the Soviets have two ground-based lasers which could be used against satellites [U.S. Department of Defense, Soviet Mfi”hry Power, 1984, p. 35],testing of such lasers as ASAT weapons would be prohibited. If these lasers had already been tested as ASATS by the time a “no new types agreement” could loIt is po9sible, of course, that one or both nations would enter into force then this regime might have to be appropri- decide–as the United States did after ratifying the ABM ately modified. Treaty–that its allowed system was not worth maintaining. 135 ——

Defensive Posture types” regime might be particularly desirable. Such an agreement could prohibit the testing Passive countermeasures appropriate in a of Soviet ground-based lasers or MV-type test-ban regime would also be appropriate in ASAT weapons and limit them to their cur- this regime, and for the same reasons. In addi- rent, unsophisticated A SAT weapon. Of course, tion, the unambiguous, if limited, threat posed this would make such an agreement less ac- by the one allowed ASAT weapon would pro- ceptable to the Soviet Union. Should the So- vide an additional incentive to deploy passive viets test advanced ASAT weapons before countermeasures tailored to that weapon. For such an agreement can enter into force, such example, evasion might effectively counter an agreement would be less advantageous to coorbital interceptors such as those tested by the United States. However, since such an the U. S. S. R., and maneuver-although not lit- agreement might avert the risks posed by even erally “evasion”- could complicate targeting more advanced-particularly directed-energy of the U.S. MV. These countermeasures would ASATs–a “no new types” agreement might probably be developed and employed even still be considered valuable and negotiable by though they would not be effective against both the United States and the Soveit Union. more capable weapons which might be developed but not tested nor deployed in space. As in the existing regime, the United States could retain a capability to negate low-altitude ECM and E-OCM would be allowed in this Soviet satellites (e.g., RORSAT) in the event regime as in a test-ban/space-based weapon of war and to respond in kind to a Soviet ban regime. Current U.S. and Soviet ASAT ASAT attack. A primary disadvantage of a weapons would be insufficiently responsive to “no new types” regime, relative to the exist- be effective for defensive shoot-back; however, ing regime, would be that allowed U.S. ASAT they could be used in retaliation. capabilities would be inadequate to negate threatening Soviet satellites if such satellites Net Assessment were moved to higher orbits—a feasible but difficult and costly Soviet countermeasure. As The primary advantage of a “no new types” in the test ban and space-based weapon ban regime, relative to the existing regime, would regime, the testing of some types of advanced be that critical U.S. satellites in higher orbits BMD weapons which would be allowed in the could be protected with some confidence from existing regime would be limited in this re- advanced ASAT weapons. If developed and gime. Such limitations could be slightly more used without prior testing, it is possible that restrictive than those of the ABM Treaty and such advanced A SAT weapons would not work would be very restrictive compared to a regime properly. If they did work, it would not be in which the ABM Treaty was no longer in force. clear that they could overcome the survivabil- Finally, it must be recognized that the relia- ity measures that could be given satellites in bility of protection afforded high-altitude sat- this regime. More generally, a ban on testing ellites by a ban on testing “new types” would advanced ASAT weapons would inhibit to be uncertain; there would remain some prob- some extent future arms competition in space. ability that an untested advanced ASAT, if Assuming the United States had success- suddenly deployed and used, might actually fully developed its MV ASAT, a “no new work. 136 —— — —

REGIME 5: RULES OF THE ROAD Legal Regime may be forcibly prevented from continued trespass. A legal regime providing for “keep-out zones” around satellites could be established The rationale for these rules is as follows: by a “rules of the road” agreement similar to ASAT weapons such as nuclear intercep- the “Rules of the Road at Sea” Treaty. ” As tors would have to be kept at a range of discussed in chapter 6, such an agreement several hundred kilometers from moder- would not prohibit development, testing, or de- ately hardened satellites in order to pro- ployment in space of advanced ASAT weap- tect such satellites; advanced ASAT di- ons but would, instead, attempt to enhance rected-energy weapons might have to be security by establishing rules regarding space kept much farther away. ’3 activities such as close approach of foreign sat- Satellites in geostationary orbit are al- ellites, advance notice of launch activities, ready so closely spaced that a keep-out high-velocity fly-bys, minimum separation dis- zone sufficiently large to protect satellites tance between satellites, low-altitude over- 2 from nuclear attack could not be estab- flight, and “keep-out zones. ”1 lished around such satellites without dis- ‘‘Keep-out zones’ would probably offer the placing satellites already there and reduc- closest thing to security in a “rules of the ing the number of geostationary orbital road” regime. The following “rules of the slots available to other nations in the road” are illustrative of those which might be future. agreed should it be decided that “keep-out There are now very few satellites in su- zones’ are in the U.S. national security in- persynchronous orbits,” but critical stra- terest: tegic warning and communications func- 9 tions could be performed by satellites in ● Keep 100 kilometers and three degrees such orbits. Should space systems be de- out-of-plane from foreign satellites below veloped to operate in this region, there 5,OOO km. would be adequate room to accommodate ● Keep 500 km from foreign satellites above large keep-out zones. 5,000 km except those within 500 km of There are presently few satellite orbits in geosynchronous altitude. deep space’s but below geosynchronous ● One pre-announced close approach at a orbital altitude. The most notable excep- time is allowed. tions are the orbits of various Soviet sat- ● In the event of a violation of the rules ellites in highly elliptical, semi-synchro- above, the nation of registry of the satel- nous “Molniya-type” orbits, U.S. Air lite which most recently initiated a ma- Force Satellite Data System (SDS) satel- neuver “burn” is at fault and guilty of lites in similar highly elliptical orbits, and trespass. U.S. (NAVSTAR) and Soviet (GLONASS) ● Satellites— trespassing upon keep-out zones navigation satellites in semi-synchronous ‘116 UST 794, TIAS 5813. circular orbits. Although there are, or ’21n addition to agreeing to such “rules of the road, ” the soon will be, many such satellites de- United States and the Soviet Union might have to modify their commitment to the 1967 Outer Space Treaty (18 U.S.T. 2410; T. I.A.S. 6347). Since Article 11 of the Outer Space Treaty states “In re: NDEW, see, e.g., L.A. Wojcik, “Separation Require- that “outer space . . . is not subject to national appropriation ments for Protection of High-Altitude Satellites from Coorbi- by claim of sovereignty, by means of use or occupation, or by tal Anti-Satellite Weapons, ” (Pittsburgh, Pa.: Carnegie-Mellon any other means, ” this could be interpreted as prohibiting estab- University, Department of Engineering and Public Policy, dis- lishment of such keep-out zones. A contrary argument main- sertation, March 1985); in re: NPB weapons, see ch. 4 of this tains that a precedent for “keep-out zones” can be found in the report. international acceptance of the principle that a satellite should “I. e., higher than geosynchronous orbitaJ altitude. not be placed in geostationary orbit if it will interfere with a “I. e., higher than 3,000 nautical miles, or about 5,600 satellite already in that orbit, kilometers. 137

ployed, several satellites will (or could) oc- ously. Therefore, adequately hardened, cupy the same orbit. For example, 24 low-altitude satellites could not be in- NAVSTAR satellites will occupy only stantly and simultaneously destroyed by three orbits, with eight satellites follow- relatively primitive ASAT weapons. ing one another around each of the three ● There would be some value in allowing orbits. Hence there would be enough room one pre-announced close approach at a in this region of space to accommodate time as an exception to the rules above. keep-out zones of several hundred kilom- Such an exception would, for example, eters radius around the satellites pres- permit an inspection satellite carrying a ently deployed there. gamma-ray spectrometer to trail a foreign ● There are too many satellites in 1ow-Earth satellite while trying to determine whether orbit—particularly below the inner Van the foreign satellite carried fissionable Allen radiation belt which extends from material, possibly in violation of Article about 1,800 km (1,000 nmi) to about 5,600 IV of the 1967 Outer Space Treaty. A dis- km (3,000 nmi)–to accommodate keep- advantage of such an exception would be out zones of several hundred kilometers that a trailing “inspection” satellite could radius around the satellites presently de- carry a weapon and destroy the trailed ployed there. Indeed, many satellites have satellite at close range. However, deploy- perigees within several hundred kilome- ment of one on-orbit spare for any truly ters of the Earth’s surface. Requiring essential satellite would eliminate this keep-out zones of several hundred kilom- risk. eters radius around low-altitude satellites Although, given adequate space surveil- would therefore be impractical. lance, it could be verified that two foreign s However, it would be feasible to establish satellites approached one another more smaller keep-out zones around satellites closely than would be allowed by these in low orbit and, in addition, to prohibit rules, there could be a problem in deter- satellites from entering an orbital plane mining which nation or other party would inclined less than, say, three degrees from be guilty of a violation. It is difficult to the orbital plane of a foreign satellite at predict, to within an accuracy of 100 km, such altitudes. Specifying a minimum an- where a satellite will be in several months gular separation between orbital planes as the result of an orbital transfer or would prevent continuous trailing; for ex- stationkeeping maneuver. This is particu- ample, two satellites in 1,000 km circular larly true if the satellite is at very low al- orbits with orbital planes separated by titude where it would be subject to atmos- three degrees would approach each other pheric drag or at very high altitude where closely every 53 minutes, if properly it would be subject to the lunar gravita- “phased,” but would separate by as much tional field. Hence, inadvertent close ap- as about 400 km at intermediate times proach might be possible. legal allocation and would be separated by at least 200 of responsibilities in such a regime might km about half the time. If, in addition, follow precedents established in maritime such satellites were phased so as to not and, especially, aeronautical law, which approach one another more closely than specifies minimum separation distances 100 km at any time, their separation between aircraft and gives right-of-way to would vary between 100 km and more relatively unmaneuverable aircraft such than 400 km, at minimum. Under such as aerostats (balloons) and gliders. One rules, although satellites would occasion- possibility would be to give right-of-way ally approach one another so closely as to to satellites already in orbit and, by im- be mutually vulnerable to, for example, plication, to assign fault to whichever covert on-board nuclear weapons, such ap- spacecraft most recently initiated or con- proaches would not all occur simultane- tinued a maneuver “burn.” 138

The rules suggested above are intended to might otherwise be able to distinguish decoys be illustrative rather than precise. Careful from valuable satellites (see discussion in framing of an agreement would be required in chapter 4). The deployment of DSATS or self- order to prohibit unintended abuses such as defense weapons would also be attractive, be- establishment of a de facto barrier to deep cause such weapons could be used to enforce space by deploying many small satellites in agreed keep-out zones. In the existing regime, low orbit in order to fill an altitude band with attempts to enforce a declared keep-out zone keep-out zones. Rationing keep-out zones— by firing upon a “violating” suspected (but not e.g., 10 per nation —could solve this problem, proven) A SAT would probably be considered but careful study may be required to foresee unlawful unless lethal capability and hostile other possible abuses. In addition to its tech- intent of such spacecraft could be established. nical problems, this regime is likely to have a significant political dimensions inasmuch as it will affect the rights of all present and fu- Net Assessment ture spacefaring nations. An agreement establishing minimum satellite separation rules could establish important Offensive Posture legal rights to actively defend satellites, and would be an improvement over the existing re A “keep-out zone” agreement would not gime if an active defense posture were desired. constrain offensive postures, and these could Enforcing agreed keep-out zones using DSATS be as in the existing regime. The protection would provide protection against relatively afforded by defended keep-out zones would primitive ASAT weapons such as the current diminish the effectiveness of some types of Soviet coorbital interceptor. However, keep- weapons such as coorbital interceptors and out zones large enough to protect satellites thereby diminish incentives to include them from advanced directed-energy weapons could in a space order of battle. However, the effec- be accommodated only beyond geosynchro- tiveness of advanced ASAT weapons—e.g., nous altitude. directed-energy weapons–would not be significantly reduced by keep-out zones of the size A “keep-out zone” regime would have the considered here. advantage of not limiting research, development, and deployment of ASAT, DSAT, and Defensive Posture BMD technologies. On the other hand, since a defended “keep-out zone” would provide sig- A “keep-out zone” agreement would not nificant protection against current ASAT constrain defensive postures, and these could weapons, it would encourage the development be as in the existing regime. Decoys might be of more advanced systems. Such systems an attractive defensive measure in this regime, would likely increase in sophistication until the because “keep-out zones” would inhibit or pre more advanced directed-energy technologies re elude certain types of close inspection which duced the effectiveness of “keep-out zones. ”

REGIME 6: SPACE SANCTUARIES Legal Regime Such an agreement would be similar in some respects to the Antarctic Treaty,lG the Outer A legal regime prohibiting the deployment Space Treaty,” the Treaty for the Prohibition of weapons in deep space (i.e., at altitudes greater than 3,000 nmi (5600 km)) or the test- - “The text of the Antarctic Treaty is reprinted in U.S. Arms ing of any weapons against instrumented tar- Control and Disarmament Agency, Arms Control and Disar- mament Agreements (Washington, D. C.: U.S. Government gets or other objects in deep space could be Printing Office, 1982), pp. 22-26. established by a “Deep-Space Sanctuary. ” “ibid., pp. 51-55. 139 of Nuclear Weapons in Latin America,18 the However, as in a “keep-out zone” regime, pas- so-called Seabed Arms Control Treaty,lg and sive countermeasures could not economically other treaties and agreements which establish protect large and expensive satellites as high demilitarized or deweaponized zones. Such an as in geosynchronous orbit from advanced agreement would not prohibit development, directed-energy weapons, which would be al- testing, or deployment in space of ASAT lowed in low orbit and which could be ade- weapons but would attempt to enhance secu- quately tested against instrumented target rity by banning the testing and deployment satellites in low orbit. As in the existing re- of weapons in deep space where critical stra- gime, small, inexpensive satellites might be tegic satellites are presently based. At present, protected from such advanced weapons be- such systems are invulnerable to currently cause they might cost more to attack than to operational tested ASAT weapons. build. In addition to such an agreement, other rele Active countermeasures appropriate in the vant agreements currently in force (Limited existing regime would also be appropriate in Test Ban Treay, Outer Space Treaty, ABM this regime, and for the same reasons. As in Treaty) could remain in force in a “deep-space the existing regime, attacking suspicious ap- sanctuary’ regime. Amendment of the Outer proaching ASAT weapons would be unlawful Space Treaty would not bean issue, since, un- at low altitudes where such objects would have like the “keep-out zone” regime, the “space rights of innocent passage. Deployment in sanctuary” regime could not be considered as deep space of “shoot-back” capabilities or a national appropriation of space. DSATS would probably be prohibited since it might be impossible to differentiate these Offensive Posture weapons from offensive weapons.

Offensive postures appropriate in a “keep- Net Assessment out zones” regime [regime 5] would also be appropriate in a deep-space sanctuary regime, The primary advantage of this regime would and for the same reasons. However, nuclear be that it could protect satellites in high or- or kinetic-energy weapons—which would re- bits from the current generation of ASAT quire more time to reach a satellite in deep weapons. In addition, a deep-space sanctuary space than to reach a satellite inside a small regime would constrain ASAT development keep-out zone—would be less attractive as less than would a comprehensive test ban re- ASAT weapons than in a “keep-out zones’ re gime or a nonew-types regime. However, should gime. Advanced directed-energy weapons, the United States and the Soviet Union choose when feasible, would be the most capable to pursue advanced ASAT weapons, a space ASAT weapons allowed in this regime, as in sanctuary might offer only limited protection. a “keep-out zones” regime. The greatest risks in a space sanctuary regime would be posed by advanced directed- Defensive Posture energy weapons which could be tested and de- Passive countermeasures appropriate in a ployed at low altitudes. Such testing and de- “keep-out zone” regime would also be appro- ployment would probably be adequate to guar- priate in this regime, and for the same reasons. antee effectiveness against targets at higher altitudes. Satellites at very high, supersyn- chronous altitudes might still derive some pre ‘aIbid., pp. 64-75; the texts of Protocols I and 11 thereto are tection from this regime, but violation of the reprinted in ibid., pp. 76 and 77, respectively. sanctuary by highly maneuverable kinetic- g ‘ Formally titled “Treaty on the Prohibition of the Emplace- energy weapons or by satellites covertly car- ment of Nuclear Weapons and Other Weapons of Mass Destruc- tion on the Seabed and the Ocean Floor and in the Subsoil rying powerful nuclear or directed-energy Thereof, ” the text of which is reprinted in ibid., pp. 103-105. weapons would remain a risk. 140 ———

REGIME 7: A SPACE-BASED BMD REGIME Legal Regime lites would probably remain vulnerable to attack by larger weapons or by expendable If the United States or the Soviet Union single-shot weapons (e.g., single-pulse lasers) withdrew from the ABM Treaty, this would, which could attack from great range unless in addition to allowing ballistic missile de- held at bay by large “keep-out zones. ” As dis- fense, eliminate constraints on ASAT capabil- cussed in chapter 4, it is possible that future ities now imposed by that Treaty. The result- technological advances might allow decoys to ing regime would allow both advanced ASAT be developed that were cost-effective when and space-based BMD weapons. Withdrawal compared to future offensive weapons and dis- from the Limited Test Ban Treaty and the crimination capabilities. Outer Space Treaty would also be necessary if the United States or the Soviet Union In evaluating offensive and defensive pos- desired to test and deploy space weapons that tures in a space-based BMD regime, it is nec- used nuclear explosives as a power source. essary to assume that future technology will confer an advantage to ASAT countermeas- Offensive Posture ures vis-a-vis ASAT capabilities. Although such an assumption may be unjustified at In a space-based BMD regime, ASAT op- present, if the United States is to deploy ad- tions would be less constrained than in the ex- vanced space-based BMD weapons then it isting regime and advanced ASAT weapons must also have developed highly effective would be more essential for defeating space- countermeasures to ASAT weapons. It would based enemy BMD system. In such a regime, be irrational for the United States to seek to advanced space-based weapons could be de- establish a “spac~based BMD” regime unless ployed at low altitudes and used as ASAT or it judged that adequate numbers of the space- DSAT weapons as well as for BMD. Some based BMD components would survive or un- spacebased weapons which would be useful— less it judged that non-space-based BMD com- but not preferred-for satellite negation might ponents could provide an adequate defense be deployed in this regime because of their use without spacebased components. Scenarios il- fulness as BMD weapons. For example, ki- lustrating each of these conditions are im- netic-energy weapons and continuous-wave aginable; for example: lasers which could destroy fast-burn boosters 1. The United States may judge that BMD deep within the atmosphere might be preferred systems with space-based components as BMD weapons over neutral particle beam could not be destroyed by the U. S. S. R.: or X-ray laser directed-energy weapons. The For example, the United States might de- latter, although more useful in an ASAT role, ploy, in addition to ground-based BMD could not readily penetrate the atmosphere components, spacebased electromagnetic and therefore may have more limited value as launchers for kinetic-energy weapons and BMD weapons. defend them by hardening, deception, and shoot-back. Deceptive measures employed Defensive Posture might include massive decoys made from zo In a space-based BMD regime, defensive asteroidal material such as nickel. While measures would be less constrained and more —. 20 essential than in the existing regime. Ad- It is speculated that the cost of transporting such material to low Earth orbit and refining and fabricating finished prod- vanced space-based weapons could be de- ucts with it there may eventually be several orders of magni- ployed at low altitudes and then used as tude lower than the cost of refining and forming such materi- ASAT or DSAT weapons. In a DSAT role, als on Earth and transporting the products to space. Should this forecast prove accurate, deception may have a favorable these weapons could offer some protection to cost-exchange ratio even against ASAT systems which can dis- low-altitude satellites. However, such satel- criminate decoys on the basis of mass density. 141 — .—

the Soviets might be able to destroy some feasibility of highly effective, advanced-tech- BMD components, the system as a whole nology BMD systems, suggesting that the de would survive. ployment of such systems, if feasible, would 2. The United States may judge that space- be desirable. Before the United States de- based BMD components would not be deployed space-based BMD systems it would stroyed by the U. S. S. R.: Even if future have to determine, first, that the contribution technology does not favor A SAT counter- that such systems made to U.S. security was measures to the extent assumed in (l), great enough to compensate for the threat A SAT countermeasure technology could which similar opposing systems would pose to be so effective that the Soviet leadership U.S. satellites, and second, that space-based would be unwilling to pay the costs of BMD components could be protected at com- defeating the countermeasures. petitive cost against advanced ASAT 3. The United States may desire an exten- weapons. sive BMD system without space-based The threat to satellites would be greater in components: For example, U.S. aspiration a space-based BMD regime than in any other might be limited to defense of hardened regime because the BMD weapons would facilities which house strategic retaliatory likely have extensive ASAT capabilities. The forces or command and control systems; expense of equipping all military satellites this might be accomplished using ground- with countermeasures against such capabil- based radars and interceptors but would ities would be considerable, particularly if, as require deployment of more of these over some fear, deployment of space-based BMD larger areas than is allowed by the ABM systems will lead to a major arms race in both Treaty. Alternatively, the United States offensive and defensive weapons. However, if, might desire an extensive BMD system as some argue, space-based missile defenses capable of defending industry and popu- can make us more secure and encourage the lation using only ground-based weapons. Soviets to make real reductions in offensive missiles, this would reduce the threat of Net Assessment U.S./Soviet conflict and to contribute to a Depending on one’s viewpoint, the principal mutual desire to protect space assets. In a advantage, or disadvantage, of a space-based world where conflict was less likely, satellite BMD regime would be that it would allow the vulnerability would be less important. United States and the Soviet Union to deploy A SAT countermeasures must prove to be ef- highly capable weapons in space. Since even fective for spacebased BMD platforms if a de a limited BMD system would probably make cision to deploy them is to make sense. It is a very good A SAT system decision to proceed possible that large improvements in the effec- with BMD deployment necessarily includes a tiveness or economy of passive countermeas- decision not to proceed with certain types of ures such as combinations of hardening, de- ASAT arms control.” ception, and proliferation might provide the On March 23, 1983, the President called for needed protection. If such improvements oc- a vigorous research program to determine the cur, they might also be used effectively for satellites in the other regimes discussed above. Alternatively, the superior fire-power or massive shielding of BMD weapons might give “lt is p~ssiblc that in a space-based BMD regime one might also wish to negotiate ‘ ‘rules of the road’ such as “keep-out them a degree of protection unattainable by zones, or perhaps ex’en a deep-space sanctuary. smaller, less capable satellites. Appendix A Soviet Draft Treaty on the Prohibition of the Use of Force in Outer Space and From Space Against the Earth —

Appendix A Soviet Draft Treaty on the Prohibition of the Use of Force in Outer Space and From Space Against the Earth U.N. General Assembly document A/38/194, Aug. 22, 1983

The States Parties to this Treaty, stroy any targets on the Earth, in the atmos- Guided by the principle whereby Members of the phere or in outer space. United Nations shall refrain in their international 3. Not to destroy, darnage, disturb the normal relations from the threat or use of force in any functioning or change the flight trajectory of manner inconsistent with the purposes of the space objects of other States. United Nations, 4. Not to test or create new anti-satellite sys- Seeking to avert an arms race in outer space and tems and to destroy any anti-satellite systems thus to lessen the danger to mankind of the threat that they may already have. of nuclear war, 5. Not to test or use manned spacecraft for mil- Desiring to contribute towards attainment of itary, including anti-satellite, purposes. the goal whereby the exploration and utilization of outer space, including the Moon and other celes- Article 3 tial bodies, would be carried out exclusively for peaceful purposes, The State Parties to this Treaty agree not to as- Have agreed on the following: sist, encourage or induce any State, group of States, international organization or natural or le- Article 1 gal person to engage in activities prohibited by this Treaty. It is prohibited to resort to the use or threat of force in outer space and the atmosphere and on the Article 4 Earth through the utilization, as instruments of destruction, of space objects in orbit around the 1. For the purposes of providing assurance of Earth, on celestial bodies or stationed in space in compliance with the provisions of this Treaty, any other manner. each State Party shall use the national tech- It is further prohibited to resort to the use or nical means of verification at its disposal in threat of force against space objects in orbit a manner consistent with generally recognized around the Earth, on celestial bodies or stationed principles of international law. in outer space in any other manner. 2. Each State Party undertakes not to interfere with the national technical means of verifica- Article 2 tion of other States Parties operating in accordance with paragraph 1 of this article. In accordance with the provisions of article 1, States Parties to this Treaty undertake: Article 5 1. Not to test or deploy “by placing in orbit around the Earth or stationing on celestial 1. The States Parties to this Treaty undertake bodies or in any other manner any space- to consult and co-operate with each other in based weapons for the destruction of objects solving any problems that may arise in con- on the Earth, in the atmosphere or in outer nection with the objectives of the Treaty or space. its implementation, 2. Not to utilize space objects in orbit around the . Consultations and co-operation as provided in Earth, on celestial bodies or stationed in outer paragraph 1 of this article may also be under- space in any other manner as means to de- taken by having recourse to appropriate in-

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temational procedures within the United Na- Article 10 tions and in accordance with its Charter. Such 1. This Treaty shall be open to all States for sig- recourse may include utilization of the serv- nature at United Nations Headquarters in ices of the Consultative Committee of States New York. Any State which does not sign this Parties to the Treaty. treaty before its entry into force in accordance 3. The Consultative Committee of States Parties with paragraph 3 of this article may accede to the Treaty shall be convened by the deposi- to it at any time. tary within one month after the receipt of a 2. This Treaty shall be subject to ratification by request from any State Party to this Treaty. signatory States. Instruments of ratification Any State Party may nominate a representa- and accession shall be deposited with the tive to serve on the Committee. Secretary-General of the United Nations. 3. This Treaty shall enter into force between the Article 6 States which have deposited instruments of Each State Party to this Treaty undertakes to ratification upon the deposit with the Secre- adopt such internal measures as it may deem nec- tary-General of the United Nations of the fifth essary to fulfil its constitutional requirements in instrument of ratification, provided that such order to prohibit or prevent the carrying out of any instruments have been deposited by the activity contrary to the provisions of this Treaty Union of Soviet Socialist Republics and the in any place whatever under its jurisdiction or United States of America. control. 4. For States whose instruments of ratification or accession are deposited after the entry into force of this Treaty, it shall enter into force Article 7 on the date of the deposit of their instruments of ratification or accession. Nothing in this Treaty shall affect the rights and 5. The Secretary-General of the United Nations obligations of States under the Charter of the United Nations.

Article 8 Any dispute which may arise in connection with the implementation of this Treaty shall be settled exclusively by peaceful means through recourse to the procedures provided for in the Charter of the United Nations.

Article 9 This Treaty shall be of unlimited duration.