Which of the following is the best evidence that Cold War fears affected American civil liberties during the 1950s?

The McCarthy Senate hearings are the clearest evidence because they investigated and publicly accused people of communist ties, often damaging reputations and raising concerns about free speech and due process. They show Cold War fears directly affecting civil liberties in the United States. The Soviet atomic bomb and the arrest of spies contributed to fear, but do not show its impact on Americans’ rights as directly.

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