According to the United States, the Strategic Offensive Reductions Treaty reduces the number of "operationally deployed strategic warheads," i.e., those warheads that are mated to their delivery vehicles and ready for launch. But the complete nuclear arsenals of the United States and Russia include many other weapons. In addition to those deployed strategic weapons, both countries deploy tactical nuclear weapons-- which are designed for battlefield use, are generally less powerful, and have a shorter range-and store thousands of additional warheads.
Currently, the total U.S. nuclear stockpile is estimated to consist of almost 11,000 warheads, including almost 7,000 deployed strategic warheads; more than 1,000 operational tactical nuclear warheads; and almost 3,000 reserve strategic and tactical warheads, which are not mated to delivery vehicles. (The United States also maintains thousands of nuclear warhead components that could be reassembled into functional weapons.)
The current Russian nuclear stockpile is estimated to include about 5,000 deployed strategic weapons, about 3,500 operational tactical nuclear weapons, and more than 11,000 stockpiled strategic and tactical warheads, for a total arsenal of about 19,500 nuclear warheads. Unlike the United States, Russia possesses these reserves at least in part because dismantling the warheads has proven prohibitively expensive. And unlike the United States, Russia continues to produce limited numbers of new nuclear warheads, largely because its warheads are designed to have far shorter operational lives and therefore must be replaced more frequently.
Strategic Nuclear Arms Control Agreements
Begun in November 1969, the Strategic Arms Limitation Talks (SALT) had produced by May 1972 both the Anti-Ballistic Missile (ABM) Treaty, which bans nationwide strategic missile defenses, and the Interim Agreement, an executive-legislative agreement that capped U.S. and Soviet ICBM and SLBM forces. Under the Interim Agreement, both sides pledged not to construct new ICBM silos, not to increase the size of existing ICBM silos "significantly," and capped the number of SLBMs and SLBM-carrying submarines. The agreement ignored strategic bombers and did not address warheads, leaving both sides free to enlarge their deployed forces by adding multiple warheads to their ICBMs and SLBMs and increasing their bomber-based forces. The agreement limited the United States to 1,054 ICBM silos and 656 SLBM launch tubes. The Soviet Union was limited to 1,607 ICBM silos and 740 SLBM launch tubes.
In-November 1972, Washington and Moscow agreed to pursue a follow-on treaty to SALT I. SALT II, signed in June 1979, initially limited U.S. and Soviet ICBM, SLBM, and strategic bomber-based nuclear forces to 2,400 delivery vehicles (defined as an ICBM silo, a submarine missile-launch tube, or a bomber) and placed a variety of other restrictions on deployed strategic nuclear forces. (The treaty called for reducing the limit to 2,250 delivery vehicles in 1981.) The agreement would have required the Soviets to reduce their forces by roughly 270 delivery vehicles, but U.S. forces were below the limits and could actually have been increased. However, President Jimmy Carter asked the Senate not to consider SALT II for its advice and consent after the Soviet Union invaded Afghanistan in December 1979, and the treaty was not taken up again. Both Washington and Moscow subsequently pledged to adhere to the agreement's terms despite its failure to enter into force. But on May 26, 1986, President Ronald Reagan said that future decisions on strategic nuclear forces would be based on the threat posed by Soviet forces and "not on standards contained in the SALT structure."
The Strategic Arms Reduction Treaty (START I), first proposed in the early 1980s by President Ronald Reagan and finally signed in July 1991, required the United States and the Soviet Union to reduce their deployed strategic arsenals to 1,600 delivery vehicles, carrying no more than 6,000 warheads as counted using the agreement's rules. …