Abraham Lincoln vs. Franklin Delano Roosevelt

[All Along The Watchtower]

Both were tyrannical dictators (Libertarian-CA).

Seriously though, while both of them faced crises that were an order of magnitude higher than what the US faces today, the fact that Lincoln was greeted upon his election with an entire region of the country seceding and then the bloodiest domestic conflict (by far) in America's history just seems like a more urgent challenge than the admittedly still-unbelievable challenge of  30+ percent unemployment and the threat of domestic conflict (revolution), but not the reality of it.

World War II and its related events gives FDR a formidable legacy in international affairs, but that war did not literally tear the country apart like the American Civil War did (if anything, quite the opposite; WWII was arguably the most unifying conflict in American history, certainly one of them, at least).