Final answer:
Senator Joseph McCarthy was a congressional champion of purging the government during the second Red Scare.
Step-by-step explanation:
Senator Joseph McCarthy was a congressional champion of purging the government of 'un-American' people during the second Red Scare. McCarthy was a U.S. Senator from Wisconsin who led a campaign in the early 1950s to expose alleged Communist infiltration in the U.S. government. Through his Senate hearings and accusations, McCarthy gained national attention and his actions became known as McCarthyism.
Learn more about The second Red Scare and McCarthyism