The Cuban missile crisis: fifty years ago next month, the U.S. and the Soviet Union came dangerously close to nuclear war.

• Author: Depalma, Anthony
• Position: TIME PAST: 1962

On Oct. 22, 1962, Americans went to bed thinking the United States was about to get into a nuclear war with the Soviet Union.

That night, President John F. Kennedy had gone on TV to tell the nation that the Soviets had secretly installed nuclear missiles in Cuba that were aimed at American cities. What followed was a 13-day standoff that underscored how easily the Cold War between the U.S. and Communist powers could have turned red-hot.

Kennedy, then in only his second year as president, made it clear he wouldn't allow the missiles to remain in Cuba, just 90 miles from Florida. But he struggled over how to get them removed without triggering a nuclear war with the Soviets that could have killed tens of millions on both sides.

"That was the point in the Cold War where the probability of a full-scale war between us and the Soviet Union was at its greatest," says Timothy McKeown, a political scientist at the University of North Carolina at Chapel Hill.

The U.S. and the Soviet Union had been allies during World War II. But after the war, the Soviets began setting up Communist puppet regimes across Eastern Europe and setting the stage for the Cold War--a decades-long period of hostility between Communism and capitalist Western nations led by the U.S.

For a while, the U.S. had a monopoly on nuclear weapons, which it had developed during World War II. But that changed in 1949 when it became clear the Soviet Union had developed its own nuclear bomb. With the prospect of an all-out nuclear war suddenly a reality, many families in the U.S. built underground bomb shelters and schools showed students how to "duck and cover" under their desks in case war broke out.

Why Cuba?

The U.S. is thousands of miles from Moscow, the Soviet capital. But the threat of Communism arrived at America's doorstep in 1959, when Fidel Castro staged a revolution in Cuba and soon allied his nation with the Soviet Union. Believing the Cuban population would support his plan, President Kennedy in 1961 backed a group of Cuban exiles in their effort to overthrow Castro and his Communist regime. The invasion at the Bay of Pigs ended with most of the U.S.-trained combatants captured or killed, and Kennedy embarrassed and frustrated.

Castro, however, was worried the U.S. would try to overthrow him again. And Nikita Khrushchev, the Soviet leader, was determined not to let the only Communist nation in the Western Hemisphere fall. Though he wouldn't admit it, Khrushchev also knew the U.S. had far more nuclear weapons than the Soviet Union, and that some were stationed in Turkey, less than 200 miles from the Soviet border. He thought that by moving nuclear missiles to Cuba, he would not only help close the "missile gap" with the U.S., but also prevent another American invasion of Cuba.

In the summer of 1962, Khrushchev began secretly shipping missiles, planes, and troops to Cuba. He believed that by the time the U.S. found out, it would have no choice but to live with the missiles, just as the Soviets had to live with the American missiles near their border with Turkey.

But keeping such a large-scale operation secret proved impossible. In an early-morning meeting at the White House on Oct. 16, 1962, Kennedy was told that an American military reconnaissance jet had taken hundreds of photos that showed conclusively that a Soviet nuclear missile base was being...