<P> The Cuban Missile Crisis, also known as the October Crisis of 1962 (Spanish: Crisis de Octubre), the Caribbean Crisis (Russian: Карибский кризис, tr . Karibsky krizis, IPA: (kɐˈrjipskjɪj ˈkrjizjɪs)), or the Missile Scare, was a 13 - day (October 16--28 1962) confrontation between the United States and the Soviet Union concerning American ballistic missile deployment in Italy and Turkey with consequent Soviet ballistic missile deployment in Cuba . The confrontation is often considered the closest the Cold War came to escalating into a full - scale nuclear war . </P> <P> In response to the failed Bay of Pigs Invasion of 1961 and the presence of American Jupiter ballistic missiles in Italy and Turkey, Soviet leader Nikita Khrushchev decided to agree to Cuba's request to place nuclear missiles on the island to deter a future invasion . An agreement was reached during a secret meeting between Khrushchev and Fidel Castro in July 1962 and construction of a number of missile launch facilities started later that summer . </P> <P> The 1962 United States elections were under way, and the White House had for months denied charges that it was ignoring dangerous Soviet missiles 90 miles (140 km) from Florida . The missile preparations were confirmed when an Air Force U-2 spy plane produced clear photographic evidence of medium - range (SS - 4) and intermediate - range (R - 14) ballistic missile facilities . The U.S. established a military blockade to prevent further missiles from reaching Cuba; Oval Office tapes during the crisis revealed that Kennedy had also put the blockade in place as an attempt to provoke Soviet - backed forces in Berlin as well . It announced that they would not permit offensive weapons to be delivered to Cuba and demanded that the weapons already in Cuba be dismantled and returned to the Soviet Union . </P> <P> After a long period of tense negotiations, an agreement was reached between U.S. President John F. Kennedy and Khrushchev . Publicly, the Soviets would dismantle their offensive weapons in Cuba and return them to the Soviet Union, subject to United Nations verification, in exchange for a U.S. public declaration and agreement to avoid invading Cuba again . Secretly, the United States also agreed that it would dismantle all U.S. - built Jupiter MRBMs, which had been deployed in Turkey against the Soviet Union; there has been debate on whether or not Italy was included in the agreement as well . </P>

Why was the u.s concerned about the missile sites in cuba