The document discusses the Red Scare period of the 1950s in the United States. It describes how fears of communist subversion and infiltration led to investigations by the House Un-American Activities Committee. Notable examples included investigations into the film industry that blacklisted the "Hollywood Ten" and Senator Joseph McCarthy's accusations of communists in the government without clear evidence. The period saw intensified fears of communism and efforts to root out perceived communist threats that some argue went too far.