How does this tie in with the Cold War?
McCarthy was a senator that was the United States to believe that there was 205 communists living in the U.S.. His speech was much different from any others, his just gave fear to all. He had said there was a list that had 57 of the communist. This soon was known as McCarthyism, which just was a way of trying to make people scarred by spreading lies. His plan soon failed, then he faded from the public life completely.
How does the World/ U.S. react?
United States: This scarred the United States, which was what McCarthy wanted from them. The Americans were angry when they had found out that it was all a lie because innocent people were being accused of communism.