"He was noted for making claims that there were large numbers of Communists and Soviet spies and sympathizers inside the federal government and elsewhere. Ultimately, McCarthy's tactics and his inability to substantiate his claims led to his being discredited and censured by the United States Senate. The term "McCarthyism," coined in 1950 in reference to McCarthy's practices, was soon applied to similar anti-communist pursuits. Today the term is used more generally to describe demagogic, reckless, and unsubstantiated accusations, as well as public attacks on the character or patriotism of political opponents."
Wikipedia on McCarthyism:
McCarthyism is a term describing the intense anti-communist suspicion in the United States in a period that lasted roughly from the late 1940s to the late 1950s. This period is also referred to as the Second Red Scare, and coincided with increased fears about communist influence on American institutions and espionage by Soviet agents. Originally coined to criticize the actions of U.S. Senator Joseph McCarthy, “McCarthyism” later took on a more general meaning, not necessarily referring to the conduct of Joseph McCarthy alone.
During this time many thousands of Americans were accused of being Communists or communist sympathizers and became the subject of aggressive investigations and questioning before government or private-industry panels, committees, and agencies. The primary targets of such suspicions were government employees, those in the entertainment industry, educators, and union activists.For McCarthyism to be effective, a propaganda technique termed as “Labeling” is established to give an “us versus them” indoctrination and using terms such as “leftists”, “communists” and such to justify violent and unjust acts upon them. This labeling of supposed enemy forces (as indoctrinated in certain elements of the armed forces and police forces in the Philippines) have expanded from the mere Communist label to the Destabilizer label. The Destabilizer label refers to anyone who criticizes or opposed the policies of President Gloria Macapagal Arroyo whose legitimacy as a President is still under question due to unresolved issues of cheating in the last Philippine presidential elections.