On this day in 1962 President Kennedy announced to a shocked nation that a nearly completed Soviet missile base had been uncovered in Cuba by US spy planes.

Never before in the history of the Republic had life on earth seemed so imperilled as it sunk into the watching millions that weapons of mass destruction could soon be sited mere miles from the Florida coast.

The Soviet Union’s actions were, Kennedy informed America, a “clandestine, reckless, and provocative threat to world peace.”

Although an air strike was considered it was decided that such an attack was too provocative and risked a rapid escalation of the situation. Instead, on October 23rd a Naval blockade of Cuba would begin, Kennedy declared, to prevent anymore weapons ending up so close to American soil.

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The following day all Soviet ships - except one - seemed to have slowed their progress south and the UN’s Secretary General U Thant sent Kennedy and Khrushchev begging letters, pleading with the pair to, “refrain from any action that may aggravate the situation and bring with it the risk of war.”

The US military were informed they were now at DEFCON 2 - the highest rating since the end of the Second World War - and children around the world went to bed wondering if they would wake up again the next day.

On October 25th the US Navy tried to stop the Soviet ship Bucharest as it sneaked over the quarantine line: they failed, judging that it was not likely to be carrying offensive weapons and as such not worth escalating the situation.

Meanwhile in Moscow, the Soviet leadership agreed a compromise that might save the world from plunging into the Third World War in living memory: they would ask President Kennedy that the United States commit never again to invade Cuba, in return the USSR would withdraw its missiles from Cuba.

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The following day however Khrushchev added the caveat that the US also withdraw its missiles from Turkey: the White House agreed but only after the Soviet Union removed its own missiles from Cuba.

The Cold War would still chill international relations for some decades yet but in the fall of 1962 the world looked over the precipice of nuclear war and decided, for now, to hold back. A fragile peace remained intact.

H/T: On This Day in History