If only we had taken from the Soviets; Poland, Ukraine, Baltics, the Check Republics, besides all of Germany in the summer of 1945 the world would be a much better place.
You are right, and I agree with you on every nation you mention.
But of all the ones that FDR should have freed, it should have been Czechoslovakia. In May 1945, General Patton's troops liberated Plzen from the Germans, and were geared toward taking Prague.
But FDR's posturing with Stalin gave the entire nation (along with Poland, Hungary, Romania, Yugoslavia, etc) to the Communists.
Turning his back on Eastern Europe was FDR's biggest failure as President.