U.S. Strategic Nuclear Forces: Background, Developments, and Issues

During the Cold War, the U.S. nuclear arsenal contained many types of delivery vehicles for nuclear weapons. The longer range systems, which included long-range missiles based on U.S. territory, long-range missiles based on submarines, and heavy bombers that could threaten Soviet targets from their bases in the United States, are known as strategic nuclear delivery vehicles. At the end of the Cold War, in 1991, the United States deployed more than 10,000 warheads on these delivery vehicles. That number has declined to less than 6,000 warheads today, and is slated, under the 2002 Moscow Treaty, to decline to 2,200 warheads by the year 2012. At the present time, the U.S. land-based ballistic missile force ICBMs consists of 450 Minuteman III ICBMs, each deployed with between one and three warheads, for a total of 1,200 warheads. The Air Force recently deactivated all 50 of the 10-warhead Peacekeeper ICBMs it plans to eventually deploy Peacekeeper warheads on some of the Minuteman ICBMs. It has also deactivated 50 Minuteman III missiles. The Air Force is also modernizing the Minuteman missiles, replacing and upgrading their rocket motors, guidance systems, and other components. The Air Force had expected to begin replacing the Minuteman missiles around 2018, but has decided, instead, to continue to modernize and maintain the existing missiles.