Who was the greatest U.S. president since the 20th century?

Unemployment decreased because of the war. and defense spending really didn't go up until the start of WWII. And if you look at armaments spending in 1933, 1934, 1935 you'll see he spending less on armaments. Also don't forget we were not prepared for war that it took us almost a year to get up to speed. We spent much of 1939 and 1941, ramping up “preparedness”.

We won partly because there was a huge ocean between us the the fighting, meaning that we weren't being bombed and our industry remained intact, unlike the other waring countries. We also had resources that we could call upon within our own boarders. We also won in part because England held out long enough for us to get war production up and running. Roosevelt didn't end unemployment nor the depression, that was the result of WWII.