re: FDR was an awful president and MacArthur was an awful general.

MacArthur didn't lose the Phillipines, nobody could have held them under the circumstances. He did freeze like a deer in the headlights and failed to give orders that would have mounted a more robust defense and saved American lives. To his credit, he intended to stay in the Phillipines and die with his men. When he was ordered out, he expected to be courtmartialed. Instead he was awarded the Medal of Honor for propaganda and morale reasons.

Given another chance at command, he saved Australia. When he went on the offensive, he incurred fewer casualties than any other major command of the war.

As de facto Viceroy of Japan, his leadership was nothing short of inspired. He took back the Korean peninsula in a brilliant counteroffensive. Then blundered it all away by ignoring his own intelligence reports about Chinese troops massing on the border. Fired for insubordination, he could have, and indeed was urged to, Wage a divisive presidential campaign and instead chose to "fade away" into retirement. In short, perhaps the most complex figure in the history of that era.

As for FDR, he remains a polarizing figure. Whether you agree with him or not, it's quite probable he forestalled something much more radical. Both communists and fascists were itching for a second American Revolution in their own image, and a lot of desperate people were willing to listen.