The Red Scare was a larger group of people that were making accusations of people being communists. Where the Salem Witch Trials were based around the accusations of a group of young girls. Whatever the girls said went. If they accused people of witchcraft they could take people's lives, if that is what the choose. A big difference between the Red Scare and the Salem Witch Trials is the periods of hysteria.
Communism is a system of social organization in which all economic and social activity is dominated by a single and self-perpetuating political party. Joseph McCarthy also stated that he knew 57 communists in the department and called for an investigation. McCarthyism is know for the practice of making accusations of disloyalty, especially of pro-Communist activity destroyed the lives of many innocent people as did the Salem Witch Trials. Both The Red Scare and The Crucible started with small groups. Also there is not very much evidence to be convicted in either group.
A big difference between the Red Scare and the Salem Witch Trials is the periods of hysteria. The Red Scare is said to be an effect of World War 1. Many of the communist and anarchist views were the cause of the hysteria. The Salem Witch Trials had no direct cause in comparison to the Red Scare. There were some reports of witchcraft in other towns but nothing to the extent of a World War like the Red Scare. The trials expanded from a small idea of a group of girls committing witchcraft. The Red Scare developed from the main idea of World War 1.
Some big similarities is that the Red Scare had obsessive "Red Hunts" where people literally searched from communists. The Communist supporters were seen as a threat to the society and were jailed for further questioning. This is similar to the Salem Witch Trials because the witches were also jailed. They both waited questioning while being put on trial. Also during the Salem Witch Trials people were asked to identify villagers who were seen with the devil.