The U.S. bent over backwards to adhere to the Geneva protocols so as not to give the Germans any pretext to harm American POWs. In one interesting case six German prisoners killed a fellow prisoner who made disparaging remarks about Hitler and said Germany deserved to lose the War. They were court-martialed and convicted, but their sentences were stayed until about month after the War, when Truman ordered them all executed. There were over 500,000 Germans interred in America, mostly in rural areas in the South. All but two were accounted for at the end of the War. None were allowed to remain in America, though thousands of them later returned after immigrating from Germany.
Once it became known that Kurt Meyer and the 12th SS Panzer Division murdered Canadian prisoners-of-war at the Abbey Ardenne Canadian soldiers seldom took prisoners from the 12th.
Ever hear of the Chenogne massacre ?
One of the saddest things I remember hearing on the radio was a black American talking about how the German prisoner in VA were treated vs. native born blacks.