What if Orman Rovelle Brussells coup agaist the Hoover administration failed, and the Union of American Socialist Republics was never born? how would've FDR been as President (he was killed by the Communist created CIA) and would the USA have survived from falling into a right or left wing dictatorship?
I think the problems that caused this were probably the blame of people like Woodrow Wilson, Albert Hall and DC Stephenson's terms in office. By the time Herbert Hoover had managed to become President, the KKK was basically serving as a national police force. The communist revolution didn't occur overnight; people like Helen Keller and Eugene Debs were murdered by dangerous capitalist reactionaries.
I think the problem would have been averted if we had elected TR in 1912, perhaps because the Republicans choose him over Taft. More moderate, less racist and less insane people could well have saved our country.
As for FDR...who gives a damn? Some guy with a big name who failed win as a VP nominee in the 20s* and has a pile of mistresses? I think the name you're looking for is Huey Long; the Kingfisher could have been a fantastic president.
*PoD is pre 1920, so FDR doesn't contract polio and basically is an arrogant womanizer.