The New START Treaty: Central Limits and Key Provisions Updated July 30, 2021 Congressional Research Service https://crsreports.congress.gov R41219 The New START Treaty: Central Limits and Key Provisions Summary The United States and Russia signed the New START Treaty on April 8, 2010. After more than 20 hearings, the U.S. Senate gave its advice and consent to ratification on December 22, 2010, by a vote of 71-26. Both houses of the Russian parliament—the Duma and Federation Council— approved the treaty in late January 2011 and it entered into force on February 5, 2011. Both parties met the treaty’s requirement to complete the reductions by February 5, 2018. On February 3, 2021, the two parties agreed to extend the treaty for five years, as permitted in the treaty text. New START provides the parties with 7 years to reduce their forces, and will remain in force for a total of 10 years. It limits each side to no more than 800 deployed and nondeployed land-based intercontinental ballistic missile (ICBM) and submarine-launched ballistic missile (SLBM) launchers and deployed and nondeployed heavy bombers equipped to carry nuclear armaments. Within that total, each side can retain no more than 700 deployed ICBMs, deployed SLBMs, and deployed heavy bombers equipped to carry nuclear armaments. The treaty also limits each side to no more than 1,550 deployed warheads; those are the actual number of warheads on deployed ICBMs and SLBMs, and one warhead for each deployed heavy bomber. New START contains detailed definitions and counting rules that will help the parties calculate the number of warheads that count under the treaty limits. Moreover, the delivery vehicles and their warheads will count under the treaty limits until they are converted or eliminated according to the provisions described in the treaty’s Protocol. These provisions are far less demanding than those in the original START Treaty and will provide the United States and Russia with far more flexibility in determining how to reduce their forces to meet the treaty limits. The monitoring and verification regime in the New START Treaty is less costly and complex than the regime in START. Like START, though, it contains detailed definitions of items limited by the treaty; provisions governing the use of national technical means (NTM) to gather data on each side’s forces and activities; an extensive database that identifies the numbers, types, and locations of items limited by the treaty; provisions requiring notifications about items limited by the treaty; and inspections allowing the parties to confirm information shared during data exchanges. New START does not limit current or planned U.S. missile defense programs. It does ban the conversion of ICBM and SLBM launchers to launchers for missile defense interceptors, but the United States never intended to pursue such conversions when deploying missile defense interceptors. Under New START, the United States can deploy conventional warheads on its ballistic missiles, but these will count under the treaty limit on nuclear warheads. The Obama Administration and outside analysts argued that New START strengthens strategic stability and enhances U.S. national security. Critics, however, questioned whether the treaty would serve U.S. national security interests because, they argued in 2010, Russia was likely to reduce its forces with or without an arms control agreement and because the United States and Russia no longer need arms control treaties to manage their relationship. The 2018 Nuclear Posture Review confirmed that the United States would continue to implement the treaty, at least through 2021. The Trump Administration raised questions about the value of the treaty and suggested that the United States might allow it to lapse while negotiating a new treaty that would include Russia and China, and capture all types of Russian nuclear weapons. It eventually sought, but failed, to negotiate a short-term extension in the latter half of 2020. The Biden Administration announced that it would seek a five-year extension of the treaty, and Russia accepted this proposal, leading to the agreed extension on February 3, 2021. Congressional Research Service The New START Treaty: Central Limits and Key Provisions Contents Introduction ..................................................................................................................................... 1 The Extension Process .............................................................................................................. 2 Background ..................................................................................................................................... 4 Central Limits and Key Provisions .................................................................................................. 5 Central Limits............................................................................................................................ 5 Limits on Delivery Vehicles ................................................................................................ 5 Limits on Warheads ............................................................................................................ 7 Conversion and Elimination ...................................................................................................... 9 ICBM Launchers ................................................................................................................. 9 Mobile ICBM launchers ................................................................................................... 10 SLBM Launchers .............................................................................................................. 10 Heavy Bombers .................................................................................................................. 11 Mobile ICBMs ........................................................................................................................ 12 Mobile ICBMs in START ................................................................................................. 12 Mobile ICBMs in New START ........................................................................................ 13 Monitoring and Verification .................................................................................................... 15 Type One Inspections ........................................................................................................ 16 Type Two Inspections ....................................................................................................... 17 Ballistic Missile Defense ......................................................................................................... 17 Conventional Long-Range Strike ............................................................................................ 20 U.S. and Russian Forces Under New START ............................................................................... 21 U.S. Forces .............................................................................................................................. 21 Russian Forces ........................................................................................................................ 23 Ratification .................................................................................................................................... 24 U.S. Ratification Process ......................................................................................................... 24 Russian Ratification Process ................................................................................................... 25 Entry into Force and Implementation...................................................................................... 26 Consultations .................................................................................................................... 27 Reductions ........................................................................................................................ 28 Monitoring, Verification, and Compliance ....................................................................... 32 Issues for Congress ........................................................................................................................ 33 New START and Strategic Stability ........................................................................................ 33 Monitoring and Verification in New START .......................................................................... 34 New START and Ballistic Missile Defenses ........................................................................... 36 Modernization ......................................................................................................................... 37 U.S. Modernization ........................................................................................................... 38 Russian Modernization ..................................................................................................... 39 Nonstrategic Nuclear Weapons ............................................................................................... 39 New START and the U.S. Nuclear Nonproliferation Agenda ................................................. 40 U.S.-Russian Arms Control After New START ...................................................................... 41 Prospects for Further Reductions .....................................................................................