Answer: People began to fear the global disasters that would be lead from the growth of nuclear-capable countries in the 1960s.
Explanation: Since the majority of countries would develop and create weapons, this lead many other countries to do the same. This lead Americans to fear that nuclear war could happen at any time. In fact, in 1962, the United States and the Soviet Union were the reason nuclear conflict occurred. This was known as the Cuban Missile Crisis.
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