I think this is a matter of opinion. Herbert Hoover wasn't great; he was sort of petty in the sense that, when he ran against FDR and lost by a landslide, he became very conservative just to spite Roosevelt. I think the best was Woodrow Wilson. He was a pretty stand-up guy; he led the United States during World War I. After the war, he had tried to vote against forcing Germany to pay reparations, but he got sick before the Treaty of Versailles was being written, and the guy who voted for him decided to flip his vote so that Germany ended up going into debt, causing the Great Depression, which leads to World War II...