The last of America's most powerful Cold War-era nuclear bombs has been dismantled in Texas. This monster is 600 times more powerful than the atomic bomb dropped on Hiroshima in 1945. Put into service in 1962, when Cold War tensions peaked during the Cuban Missile Crisis, the B53 weighed 4,500 kg and the size of a minivan.
The B53's disassembly ends the era of big megaton bombs, with the biggest nuclear bomb in the United States’ arsenal now is the 1.2-megaton B83 compared to the B53 which was 9 megatons.
The B53 was designed to hit targets deep underground, such as bunkers in which military and civilian leaders might be sheltering and required five parachutes to land it softly on their targets before detonating an explosion, in effect simulating an earthquake. These have been superseded, now, by bombs that burrow into the ground and then explode.
According to figures released by the US state department in May 2011, the US has 5,113 nuclear warheads in its current stockpile, down from 31,255 in 1967.