Final answer:
Senator Joseph McCarthy used tactics of accusation without evidence, causing fear and making people reluctant to challenge him.
Step-by-step explanation:
Senator Joseph McCarthy employed tactics of accusation without evidence in his campaign against supposed Communist infiltration of the government during the Cold War. He would make unsupported claims and repeatedly change the number of Communists he alleged to be within the government, which gained him attention and support from some Americans.
However, few people challenged McCarthy because they feared becoming his targets for accusations of disloyalty. McCarthy's tactics created an atmosphere of fear and paranoia, causing many Americans to hesitate in speaking out against him. Additionally, some prominent Republicans supported McCarthy because they believed his campaign against Communism would benefit their party politically.
In conclusion, McCarthy's tactics of accusation without evidence and the fear he instilled in people contributed to the reluctance of many Americans to challenge him.