The greatest would have to be FDR, crippled, a world wide depression, the great war, how many could have gone through all that, and yet he screwed up with the Japanese internment. Definitely tough times, and that work laid the foundations for our liberal democracy that raised the boats for so many. LBJ continued that tough leveling task. Reagan was the beginning of the end and while I think he realized he screwed up, his ideas appealed to the greedy and imperialists and today we see the fruits of Reagan in corporate greed and an illegal war.