The Nuclear Arms Race: A World on the Edge

In October 1962, the United States and the Soviet Union came closer to nuclear war than at any other time in history. For thirteen tense days, known today as the Cuban Missile Crisis, American spy planes had photographed Soviet missile bases being built just 90 miles off the coast of Florida, on the island of Cuba.

- Explain why the United States and the Soviet Union built so many nuclear weapons - Describe what happened during the Cuban Missile Crisis in 1962 - Define the idea of 'deterrence' - Understand why the arms race finally began to slow down

The United States tested the world's first nuclear bomb in the New Mexico desert on July 16, 1945, in a test called Trinity. Just four years later, on August 29, 1949, the Soviet Union tested its own bomb, called RDS-1. Once both countries had the bomb, each worried the other might attack first. So both nations raced to build more weapons than the other, believing more bombs meant more safety. This race to build the most and the strongest weapons became known as the nuclear arms race.

In 1952, the United States tested an even more powerful weapon called a hydrogen bomb, or H-bomb, in a test named Ivy Mike. It was hundreds of times stronger than the bomb dropped in 1945. The Soviet Union built its own hydrogen bomb less than a year later, in 1953. By the height of the arms race in 1986, the United States and the Soviet Union together held about 70,000 nuclear warheads — enough destructive power to affect the entire planet many times over.

Military planners came up with an idea called deterrence: if both sides had enough weapons to destroy each other completely, neither side would dare attack first, because they, too, would be destroyed in return. This idea was nicknamed MAD, short for Mutually Assured Destruction. It sounds frightening, and it was — but for decades, leaders on both sides believed it was the very thing keeping the peace.