The crisis had been building since the Bay Of Pigs fiasco in April 1961.

The USA had incontrovertible proof that Cuba had a number of Soviet made medium range missiles capable of carrying nuclear warheads.

It is likely that Soviet leader, Nikita Khrushchev, resented that the USA had nuclear missiles stationed close to Russia and was looking to redress the balance.

From this day, and for the next 2 weeks, the world stood on the brink of nuclear war until the Soviets backed down from breaking a US blockade.

Today, in 1964, Nikita Khrushchev was ousted as leader of the Communist party, in favor of Leonid Brezhnev.