In the late 40s and early 50s the United States became involved in a new conflict, the Cold War. This time the enemy was international communism. Many people felt that the Soviet Union and new communist governments in Eastern Europe, China, and North Korea threatened international security. There was also widespread belief that American Communists and Socialists, many of whom were active in the labor movement, supported world communist revolution and posed a grave danger to democratic government and the American way of life. Congress launched sweeping investigations to weed out Communists in government, labor unions, the entertainment industry and even the army. As a result labor unions were forced to purge anyone who had ever belonged to, or had been sympathetic to, the Communist party.