Basically to stop the Russians from hitting America with the Russians bombs, even though we had nuclear bombs too which is why the entire world was kind of iffy about it because using one bomb could have destroyed the world.
communism is the short answer ;
During the Cold War, the primary concern of the United States was the spread of communism, particularly from the Soviet Union. The U.S. adopted a containment strategy, engaging in geopolitical conflicts and an arms race to counter Soviet influence. This era was marked by significant events and policies such as the Berlin Blockade and McCarthyism that reflected the intense fears and tensions of the time.
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