These were assaults ordered by Attorney General Mitchell Palmer on suspected radicals after World War I. They were controversial because of the lack of evidence that was needed to carry them out.

Palmer Raids were assaults ordered by Attorney General Mitchell Palmer on suspected radicals after World War I.

Explanation:

During November 1919 and January 1920, the doubted leftists are found and arrested by the Palmer Raids by the United States Department of Justice during the First Red Scare. The first Red Scare was about socialist revolution and political intolerance.

Palmer Raids were brought to end only after the clearance of radicals. The radicals generally belong to Italy and Easter European countries.

Red scare refers to the strong Anti-Communism in the United States of America. Attorney General Mitchell Palmer was responsible for Palmer Raids.