Cuban Missile Crisis
When the US discovered Soviet nuclear missile sites under construction in Cuba it imposed a naval blockade. For thirteen days the world stood on the brink of nuclear war until the Soviets withdrew the missiles.
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Castro’s revolution of 1959 turned Cuba towards the Soviet Union, and in 1961 a US-backed invasion by exiles at the Bay of Pigs failed. The Soviets secretly placed medium-range nuclear missiles in Cuba, and in October 1962 American reconnaissance aircraft found the sites.
On 22 October Kennedy announced a naval “quarantine” of Cuba on television, and both sides’ forces went to the highest alert. On 28 October Khrushchev announced that he would remove the missiles in return for a US pledge not to invade Cuba; the US also secretly agreed to withdraw its missiles from Turkey. Afterwards the two powers set up a hotline and in 1963 signed the Partial Test Ban Treaty.