Cuban Missile Crisis , a confrontation between the United States and the Soviet Union, October 22–28, 1962, that threatened to precipitate nuclear war. Early in the fall of 1962, American reconnaissance planes detected Soviet ballistic missiles and launching facilities in Cuba. Calling the missile deployment an escalation of the Cold War, President Kennedy on October 22 demanded that Soviet premier Nikita Khrushchev have the missiles removed and the launching facilities dismantled. He declared a "strict quarantine on all offensive equipment under shipment to Cuba," especially missiles already aboard Soviet ships. Kennedy also placed American forces on full alert, ready, if necessary, to invade Cuba or launch a nuclear strike against the Soviet Union.

For several days, nuclear war seemed imminent; however, secret diplomatic negotiations were taking place between the United States and the Soviet Union. Khrushchev eventually backed down. On October 24, Soviet ships bound for Cuba changed course, and on October 28, the Soviet Union announced that the missiles would be withdrawn from Cuba. In return, the United States pledged not to invade the island.