Defense Number 14 A publication of the Center for Technology and National HorizonsSecurity Policy JUNE 2002 National Defense University Toward Missile Defenses from the Sea by Hans Binnendijk and George Stewart Overview researchers made significant progress toward developing naval-based theater missile defenses during the Clinton administration, the basic Developments of the past 18 months have created new possibili- NMD architecture had no naval component because that administra- ties for the sea basing of national defenses against interconti- tion sought actual deployments by 2005–2006. nental ballistic missiles. Some conceivable designs would Once in office, the Bush administration was determined to enhance U.S. prospects for defeating a rogue state missile attack accelerate progress on missile defenses, expand research and devel- on the United States and its allies, but other deployments could opment efforts, accept a greater degree of technological risk, and undermine the Nation’s strategic stability with Russia and redesign NMD architecture. However, no new missile defense archi- China. The most efficacious architecture from both a technical tecture has been proposed. The clear line established in 1997 that and strategic perspective would include a U.S. Navy boost-phase delineated theater missile defenses and national missile defenses intercept program and some sea-based radar. Given the compli- became blurred. The strategy opened the door to a greater seaborne cations of using existing Aegis ships for the missile defense mis- contribution to defense against ICBMs, and the Navy began to ana- sion, the Navy should consider constructing a separate ship lyze the possibility of this new potential. The Federal Government designed solely for this purpose. developed a broad array of options to exploit the progress that had been made in Navy theater programs. Then, three events occurred Current Technology and Policy Status in December 2001 and January 2002 that further shaped the Navy The Clinton administration developed its national missile program. defense (NMD) strategy in an effort to defend all 50 states as soon as On December 13, 2001, the Bush administration announced possible against a limited intercontinental ballistic missile (ICBM) that the United States would withdraw from the ABM Treaty in June threat from rogue states. To secure the Nation’s strategic stability vis- 2002. Despite the diplomatic drawbacks of this decision, the United à-vis Russia, the plan emphasized retaining an amended version of States can now experiment with ship-based missile defenses that the the 1972 Anti-Ballistic Missile (ABM) Treaty. The resulting architec- treaty constrained. When the treaty expires in June, the Pentagon ture relied on land-based midcourse interceptors guided by land- and will test the ability of the Navy’s Aegis radar to track both intercep- space-based sensors. The technologies needed for this architecture tor and target missiles. The decision to withdraw from the ABM had not matured by September 2000, however, and President William Treaty also removes constraints from the development of naval sys- Clinton decided not to deploy the system in 2001. Although the tems designed to be effective against shorter-range ballistic missiles. Center for Technology and National Security Policy The National Defense University (NDU) established the Center for Technology and National Security Policy in June 2001 to study the implications of technological innovation for U.S. national security policy and military planning. The center combines scientific and technical assessments with analyses of current strategic and defense policy issues. Its major initial areas of focus include: (1) technologies and concepts that encourage and/or enable the transformation of the Armed Forces, (2) developments by defense laboratories, (3) investments in research, development, and acquisition and improvements to their processes, (4) relationships among the Department of Defense, the industrial sector, and academe, and (5) social science techniques that enhance the detection and prevention of conflict. The staff is led by two senior analysts who hold the Roosevelt Chair of National Security Policy and the Edison Chair of Science and Technology and who can call on the expertise of the NDU community and colleagues at institutions nationwide. The papers published in the Defense Horizons series present key research and analysis conducted by the center and its associate members. June 2002 Defense Horizons 1 As a result, tests of future sea-based systems will begin to move from need to strike Russian targets. In this context, a reasonable archi- the virtual world of high-speed computers to the test range. tecture to defend against ICBMs would: The day after announcing its intention to withdraw from the I be oriented primarily against missiles launched from rogue states ABM Treaty, the Bush administration terminated the Navy Area Mis- I try to intercept a missile as early as possible in flight before counter- sile Defense Program, the program for terminal defense against measures are dispersed and allow time for secondary attempts, if necessary short-range ballistic missiles, because of cost overruns. Until that I contain a thin layer of ground-based interceptors designed to attack point, some administration officials had envisioned using Navy Area a missile during its midcourse, should the missile leak through the first line as an emergency boost-phase interceptor against North Korean mis- of defenses.1 siles. This program had been scheduled to begin testing this year, These principles call for emphasis on boost-phase missile with operational deployment to begin by 2004. One likely conse- defense systems. Unless the boost-phase missile defense system is quence of the decision to terminate the program will be the delay of space-based, its operating area will necessarily be within about 1,000 any operational (as opposed to an kilometers of the ICBM launch experimental or test-bed) sea- boost-phase missile defense site. This range greatly limits the based missile defense system by effect that a terrestrial boost- some 2 to 5 years. systems also have the advantage phase missile defense system Then, the Navy successfully could have on Russia’s or China’s flight-tested the first fully func- of attacking an ICBM during strategic deterrents. Deploying tional Standard Missile (SM)–3 the most vulnerable portion boost-phase interceptors in space interceptor on January 25 and is not recommended because such scored a direct hit, using hit-to-kill of its trajectory deployments could intercept Russ- technology against a Scud-type test ian and Chinese missiles and missile. The SM–3 is the missile associated with the core of the Navy would therefore prove destabilizing. Similarly, deploying ground- Mid-course (formerly Navy Theater-Wide) system. The Mid-course based boost-phase interceptors would require stationing them in system is the only Navy missile defense program that enjoys any sig- Russia to deal with the North Korean threat. nificant funding—seven SM–3 test firings are now scheduled— Boost-phase missile defense systems also have the advantage although there is neither funding for procurement nor any official of attacking an ICBM during the most vulnerable portion of its tra- plan for transitioning what is currently an effort at risk reduction jectory. During the boost phase, an ICBM is a large object with a and proof of principle into a procurement program. No one is certain bright booster plume. Because of the large stresses of launch, even when project leaders will meld the technologies tested as part of the the slightest amount of damage to the ICBM can result in total Navy Mid-course program into an operational system. An optimistic destruction of the entire system. Boost-phase missile defense sys- guess is about 5 years from now; a pessimistic guess is 10 years. tems also attack the ICBM before the offense can disperse counter- These three events encouraged additional testing of naval mis- measures or multiple warheads. Another strong advantage of focus- sile defense systems while significantly delaying development of the ing on boost-phase defenses is the U.S ability to defend its allies foundations of that system. Developers are reengineering the Navy while defending itself. program, taking much of the steam out of efforts to focus it on ICBM The technical and operational challenges of the boost-phase defenses. defense require launch of the missile interceptors within 3 to 5 min- utes after missile launch. (Some advanced ICBM flight concepts, Defending the Nation against ICBMs such as fast burn and depressed trajectories, can reduce this time still further, but rogue states’ first-generation ICBMs are unlikely to One should place the U.S. Navy contribution to missile have this capability.) defenses in the context of threats from emerging rogue states and Because the development of most missile defenses to date has the need to maintain strategic stability with former adversaries. concentrated on midcourse or terminal defense, the technical chal- During the past several years, national intelligence estimates have lenges of building a system capable of detecting, identifying, track- indicated a growing missile threat from North Korea, Iran, and Iraq ing, and engaging a ballistic missile during its boost phase have not that will continue to increase throughout this decade. At the same yet been fully addressed. Even if the system were fully operable, a time,