It Couldn't Happen Here ... But It Almost Did

Wiki:

The Business Plot (also known as the Plot Against FDR or the White House Putsch) was an alleged political conspiracy in 1933 in which several wealthy businessmen planned to overthrow the presidency of Franklin D. Roosevelt.

Details of the alleged plot came to light in early 1934, when retired Marine Corps Major General Smedley Butler testified before the McCormack-Dickstein Congressional Committee. In his testimony, Butler claimed that a group of men had approached him as part of a plot to overthrow Roosevelt in a military coup. One of the alleged plotters, Gerald MacGuire, vehemently denied any such plot. In their final report, the Congressional committee supported some of Butler's allegations, but no prosecutions or further investigations followed, and the matter was mostly forgotten.

Major General Butler claimed that the American Liberty League was the plot's primary source of funding. The House Un-American Activities Committee found no evidence of this. The main backers of the American Liberty League were the Du Pont family, as well as leaders of U.S. Steel, General Motors, Standard Oil, Chase National Bank, and Goodyear Tire and Rubber Company. The 2007 BBC radio documentary The White House Coup alleged that Prescott Bush, father and grandfather to the 41st and 43rd US Presidents respectively, was also connected with companies owned by Fritz Thyssen.

Several scenarios have been proposed in explaining why the affair did not become a cause celebre, among which are:

• The story was an embarrassment to people of influence, who felt it best to deflect attention from the matter as quickly as possible.
• Some of Roosevelt's advisors were in on the plot, and downplayed it to prevent exposure.
• As part of the BBC Radio Document program The Whitehouse coup,^[3] John Buchanan suggests that Roosevelt stopped the investigation as part of a political deal: "The investigations mysteriously turned to vapor when it comes time to call them to testify. FDR's main interest was getting the New Deal passed. And so he struck a deal in which it was agreed that the plotters would walk free if Wall Street would back off of their opposition to the New Deal and let FDR do what he wanted."