What information did McCarthy cite to show that America was losing the war against Communism?

Senator Joseph McCarthy cited various pieces of information to argue that America was losing the war against Communism, including alleged infiltration of the U.S. government by Communist sympathizers and spies. He pointed to the presence of Communist influence in labor unions, educational institutions, and the media. McCarthy also referenced intelligence reports and testimonies from defectors to bolster his claims, asserting that these factors undermined American security and values. His assertions contributed to a climate of fear and suspicion during the Red Scare of the 1950s.