Harry Truman was no Harry Truman. I used to think pretty highly of him, until I saw how he treated the threat of communist subversion in our government.
It was not only far more important to him and his minions that the interests of the Democratic party were not hurt in the public eye, he approved of the destruction of individual citizens reputations to try to avoid it.
If FDR had died a year earlier giving us Henry Wallace as President, and Wallace had beaten Dewey in 1944, our foreign policy towards the Soviet Union would have been like Obama's towards Iran and Muslim extremists.