"I find hope in the work of long-established groups such as the Arms Control Association...[and] I find hope in younger anti-nuclear activists and the movement around the world to formally ban the bomb."

– Vincent Intondi
Author, "African Americans Against the Bomb: Nuclear Weapons, Colonialism, and the Black Freedom Movement"
July 1, 2020
START II and Its Extension Protocol at a Glance

Last Reviewed: 
July 2022

Contact: Daryl Kimball, Executive Director, (202) 463-8270 x107

U.S. President George H. W. Bush and Russian President Boris Yeltsin signed the Strategic Arms Reduction Treaty II (START II) on January 3, 1993.

START II established a limit on strategic weapons and required that reductions be implemented in two phases. This treaty would remain in force for the duration of START I, which entered into force in 1994, and would expire in 2009.

The United States ratified the original START II agreement in January 1996 but never ratified a 1997 protocol or the 1972 Anti-Ballistic Missile (ABM) Treaty succession, demarcation, and confidence-building agreements. The protocol shifted the deadline for completion of START II reductions from January 1, 2003, to December 31, 2007, due to the delay in ratification. The succession agreement formalized the former Soviet republics' status as parties to the ABM Treaty. The demarcation agreements clarified the demarcation line between strategic and theater ballistic missile (TBM) defenses.

On May 4, 2000, Russian President Vladimir Putin signed the resolution of ratification for START II, its extension protocol, and the 1997 ABM-related agreements. Russia's ratification legislation made the exchange of START II's instruments of ratification (required to bring it into force) contingent on U.S. approval of the extension protocol and the ABM agreements. Congress never voted to ratify the entire package.

Russia announced on June 14, 2002, that it would no longer be bound by its START II commitments, ending almost a decade of U.S.-Russian efforts to bring the 1993 treaty into force. Moscow's statement came a day after the United States withdrew from the ABM Treaty and a few weeks after the two countries concluded a new nuclear arms accord on May 24.

The new agreement, the 2002 Strategic Offensive Reductions Treaty (SORT), required the United States and Russia to reduce their deployed strategic arsenals to 1,700-2,200 warheads apiece by December 31, 2012, effectively superseded START II's requirement for each country to deploy no more than 3,000-3,500 warheads by December 2007. However, other key START II provisions, such as the prohibition against deploying multiple independently targetable reentry vehicles (MIRVs) on intercontinental ballistic missiles (ICBMs), were not addressed in the SORT agreement.

Basic Terms:

  • Deployment of no more than 3,800 to 4,250 strategic nuclear warheads on ICBMs, submarine-launched ballistic missiles (SLBMs), and heavy (long-range) bombers by December 31, 2004. This includes no more than 2,160 warheads deployed on SLBMs, 1,200 warheads deployed on ICBMs with MIRVs, and 650 warheads deployed on heavy ICBMs.
  • Deployment of no more than 3,000 to 3,500 strategic nuclear warheads on ICBMs, SLBMs, and heavy bombers by December 31, 2007. This includes no more than 1,700 to 1,750 warheads deployed on SLBMs, as well as the elimination of heavy ICBMs and the prohibition of MIRVs on ICBMs.
  • "Deactivation" of all strategic nuclear delivery vehicles slated for elimination under the treaty by removing their nuclear reentry vehicles (warheads) or taking other jointly-agreed steps by December 31, 2003.

Additional Provisions:

  •  START I definitions, limits, procedures, and counting rules applied to START II, except where explicitly modified.
  • Unlike START I, which substantially undercounts weapons deployed on bombers, the number of weapons counted for bombers would be the number they are actually equipped to carry for START II. Provided they were never equipped for long-range nuclear air-launched cruise missiles, up to 100 heavy bombers could be "reoriented" to conventional roles without physical conversion, which would not count against the overall limits. The reoriented bombers could be returned to a nuclear role, but thereafter could not be reoriented and exempted from limits.