During the Cold War the United States and the Soviet Union became engaged in a nuclear arms race. This was the result of the Soviet Union successfully testing its first atomic bomb on August 29, 1949. After the atomic bomb test, the entire world was shocked. Both countries continued building bigger bombs and In 1952, the United States tested a new and more powerful weapon, the hydrogen bomb. The Soviet Union followed with its own version in 1953.During this time, Einstein continued to work on an idea called “nuclear disarmament” Einstein feared this race would end with the destruction of civilization so he never gave up his fight for peace. This lasted until the signing of the Conventional Forces in Europe treaty of November 1990.