https://en.wikipedia.org/wiki/Smedley_Butler

In 1933, Butler claimed to have been approached to become involved in a controversy, the Business Plot, telling a United States congressional committee a group of wealthy American industrialists were planning a coup d'état to overthrow President Franklin D. Roosevelt. Butler also claimed the plotters of the alleged coup intended to use him, at the head of a group of veterans, to place the federal government under arrest. The individuals alleged to be involved in the coup all denied the existence of such a plot and the media ridiculed Butler's allegations, but a final report following an investigation by a special House of Representatives committee confirmed at least some of his testimony.