In 1919, a wave of anticommunist hysteria swept through the United States. Thousands people were arrested and imprisoned solely for their political beliefs or for belonging to labour or political organizations. The Red Scare had its immediate roots in a combination of domestic and international events. A nationwide fear of communists suddenly grabbed the American psyche and held the nation in the grips of fear. After the war, America was in uncharted territory. Nuclear weapons were new, powerful, and strangely frightening. Just when it seemed as if America had successfully asserted her strength at Hiroshima and Nagasaki, the Russians began their nuclear testing and destroyed all sense of security. Communism, too, was spreading seemingly unrestrained through the world. America immediately became aware. Senator Joseph McCarthy claimed to have lists of names of people that secretly held allegiances with the communist parties, lists that often contained names of many high ranking public officials and also celebrities. The media, which was so important in the fifties, picked up on McCarthy's "blacklists" and ran them in the papers. As a result, not only was communism a force from overseas to fear, it was a force within America's own boundaries, threatening to tear apart the post war threads that held the nation together. .
The year 1919 saw a great deal of social conflict. There was a wave of strikes, the passage of both Prohibition and Woman Suffrage, and the Chicago race riot to name a few of the major events of the time. A series of bombings by suspected radicals began in the summer of 1919 and as a result, increased panic and hysteria amongst the American people. However, the identity of those that set the bombs off remained unclear, which further added to the existing panic. Although there was only a small number self-professed communist's in the United States in 1919, Palmer viewed them as responsible for a wide range of social ills, including the bombings.