The U.S. Navy currently deploys almost one-half of all U.S. nuclear weapons. The total number of U.S. "nukes" is declining, while the percentage of U.S. weapons on board ship—specifically, in 18 Trident missile submarines—is increasing.
Today, the United States has almost 7,500 nuclear warheads, down from about 20,000 when the Cold War ended in 1991. They are carried by land-based intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), manned strategic bombers, and manned tactical bombers in Western Europe. Table 1 shows an estimate of current U.S. nuclear weapons assigned to operational forces.
Long gone are the approximately 500 shipboard nuclear weapons that populated U.S. warships in the final days of the Cold War—some 400 B57 and B61 strike bombs and depth bombs in aircraft carriers, and 100 Tomahawk land-attack missiles (TLAMs) in cruisers, destroyers, and attack submarines. Similarly discarded are the B57 nuclear depth bombs assigned to P-3 Orion maritime patrol aircraft.