The Legacy of START and Related U.S. Policies

Fact Sheet
Bureau of Verification, Compliance, and Implementation
July 16, 2009

The United States and the former Soviet Union signed the START Treaty in 1991. Pursuant to the provisions of that Treaty, due to expire in December of this year, the United States, Russia, Ukraine, Kazakhstan, and Belarus have destroyed hundreds of bombers and ballistic missiles and have removed thousands of nuclear warheads from their operational forces. These results are tremendously important.


Although the START Treaty was signed in 1991, its entry into force was delayed for three years following the breakup of the Soviet Union. Under the 1992 Lisbon Protocol, Belarus, Kazakhstan, and Ukraine joined Russia as legal successors to the START Treaty and committed to relinquishing all nuclear and strategic offensive arms. The Treaty entered into force on December 5, 1994.

The 1992 Nunn-Lugar Cooperative Threat Reduction program provides funding and support for the destruction of weapons of mass destruction in former Soviet states. It has been instrumental in helping Russia, Ukraine, Kazakhstan, and Belarus implement the Treaty.

On December 5, 2001, the United States and Russia completed all START-mandated reductions so that each party had cut the number of deployed strategic delivery vehicles to fewer than 1,600 and their attributed warheads to fewer than 6,000. Also, all nuclear weapons had been removed from Belarus, Kazakhstan, and Ukraine.

How START Works

The START Treaty reduced levels of strategic offensive arms by limiting each side's nuclear arsenal to no more than 6,000 warheads and 1,600 delivery vehicles and by placing caps on the number of warheads attributed to specific types of delivery vehicles (ICBMs, SLBMs, and heavy bombers). Under the START counting system, each type of missile or heavy bomber is attributed and assumed to be armed with a specific number of warheads. A cap was also set for both the total number of missiles and bombers, as well as for the number of attributed warheads. A core aspect of START is its verification regime which calls for detailed declarations and intrusive inspections. The United States has conducted nearly 600 inspections in Belarus, Kazakhstan, Russia, and Ukraine while Russia has conducted over 400 inspections in the United States.

The Moscow Treaty

Presidents Bush and Putin took a different approach when they signed the Moscow Treaty in 2002. That Treaty, unlike START, limits the number of actually deployed nuclear warheads and does not require the elimination of delivery platforms for them. Under the Moscow Treaty, the parties must have no more than 1,700-2,200 strategic nuclear warheads deployed by 2012. This is different than START’s attribution approach. As of May 2009, the United States had cut its number of operationally deployed strategic nuclear warheads to 2,126, which meets the limits set by the Treaty for 2012.

Post Cold War Arms Reductions

Since the end of the Cold War, the United States has:

  • Reduced the number of operationally deployed strategic nuclear warheads to roughly one third of the cold war level.
  • Unilaterally reduced non-strategic (tactical) nuclear weapons to less than one-tenth of Cold War levels.
  • Retired over 1,000 strategic ballistic missiles, 350 heavy bombers and 28 ballistic missile submarines.
  • Not produced enriched uranium for use in nuclear weapons since 1964 nor produced plutonium for nuclear weapons since 1988. In 2006, the United States proposed a global treaty that would prohibit the production of highly-enriched uranium (HEU) or plutonium for nuclear weapons.
  • Through an agreement with Russia, the United States has blended down 325 MT of HEU – enough for 13,000 nuclear weapons, for use in U.S. nuclear power plants.

Numbers of Strategic Forces Under START

United States
Category of Data
and Treaty Limit
Former USSR Parties / Russia[1]
Dec 5, 1994
Dec 5, 2001
Jan 1, 2009
Dec 5, 1994
Dec 5, 2001
Jan 1, 2009
Deployed ICBMs and SLBMs and Their Associated Launchers and Deployed Heavy Bombers: 1,600
Warheads Attributed to Deployed ICBMs and SLBMs and Deployed Heavy Bombers: 6,000


[1] All nuclear warheads and strategic offensive arms have been removed from Belarus, Kazakhstan and Ukraine.