The Cuban Missile Crisis of October 1962 was a direct and dangerous confrontation between the United States and the Soviet Union during the Cold War and was the moment when the two superpowers came closest to nuclear conflict. The crisis was unique in a number of ways, featuring calculations and miscalculations as well as direct and secret communications and miscommunications between the two sides. The dramatic crisis was also characterized by the fact that it was primarily played out at the White House and the Kremlin level with relatively little input from the respective bureaucracies typically involved in the foreign policy process.
The Soviet Union agreed to put nuclear missiles in Cuba
After the failed U.S. attempt to overthrow the Castro regime in Cuba with the Bay of Pigs invasion, and while the Kennedy administration planned Operation Mongoose, in July 1962 Soviet premier Nikita Khrushchev reached a secret agreement with Cuban premier Fidel Castro to place Soviet nuclear missiles in Cuba to deter any future invasion attempt. Construction of several missile sites began in the late summer, but U.S. intelligence discovered evidence of a general Soviet arms build-up on Cuba, including Soviet IL–28 bombers, during routine surveillance flights.