Senator Joseph McCarthy became one of the most popular politicians in the 1950s, known for his anti-communist zeal. But eager for self-promotion, McCarthy charged that hundreds of people in government agencies were secret communists, going so far as to question the anti-communism of President Eisenhower himself. His downfall came in 1954, when the Senate decided to investigate his charges that the army was harboring communists. But in the Army-McCarthy hearings, Army chief counsel Joseph Welch exposed him as a reckless, dishonest bully on national television.
I believe if these hearings had not occurred, McCarthy would have aggravated the Red Scare. If he had continued to grow more powerful, he might even have worsened already shaky relations with Russia and perhaps heated up the Cold War. America might be a much more different place if McCarthy continued to stay in power.