The arms race was a competition between the two superpowers that consisted in building up armies and stores of weapons to keep up with the enemy.
The Soviet Union had set off its first atomic bomb in 1949. In the early 1950s, the Soviet Union and the United States developed the even more deadly hydrogen bomb. By the mid-1950s, both had intercontinental ballistic missiles (ICBMs) capable of sending bombs anywhere.
Both the United States and the Soviet Union now worked to build up huge arsenals of nuclear weapons. They believed that having these arsenals would prevent war. Neither side would launch a nuclear attack, because both knew that the other side would be able to strike back with devastating power.
- Spielvogel, Jackson. Glencoe World History. E.U.A: National Geographic, 2008. P.979.