Why did many Americans come to fear communists and other radicals during the red scare after world war 1? What was the effect of the red scare?

Red scare was the promotion of fear that people had in the United States.

Explanation:

About the spread of communism in that area by the other society and this name was given because people in communism used red flags. People in the United States feared that immigrants especially from Russia would spread communism which was feared by the Americans.

It had negative effect on the society and the government of the United States where there were many protests and there was fall in production and demand of goods leading to fall in jobs.