The USA today is a multicultural society - this is largely due to the fact that a large number of people migrated there, mostly from Europe, in the early 1900s.
Many Americans were frightened by the Communist Revolution that had happened in Russia in October 1917. The American Socialist Party and the American Communist Party were established during this period. Many Americans feared the spread of communist and anarchist ideas. They viewed immigrants with increasing suspicion and became increasingly xenophobic.
There were over 3,000 cases of industrial strikes in 1919, including the Boston Police force.
Feelings of anger and animosity arose towards communists and many Americans believed that some of the events of 1919 and 1920 were linked to communism.
In September 1920, a bomb exploded on Wall Street killing 38 people, and another bomb destroyed the front of the Attorney General, A Mitchell Palmer's house.
These events gave rise to the Red Scare and fear that communism was a real danger that threatened the American way of life.
The Palmer Raids
United States Attorney General, A Mitchell Palmer organised attacks against left wing organisations. Palmer spread rumours about the Red ScareConcern regarding the spread of communist and socialist ideas. saying that there were around 150,000 communists living in the country (0.1 per cent of the population).
As many as 6,000 were arrested and held in a prison without a hearing and hundreds were deported. The Palmer Raids were a response to imaginary threats. Eventually they were released and the Red Scare receded.