Anyway, U.S. war crimes and brutality did occur, but it was far, far, far less prevalent than Soviet and Axis war crimes. U.S. soldiers weren't given carte blanche to rape and pillage Germany or Japan during the occupations, and the soldiers that did were punished for it. This wasn't generally the case with the Soviets in the areas they occupied immediately after the war.
To be fair, the american soldiers only had extensive contact with civilian populations on France and Italy before entering on Germany, they saw the french and other nations as allies to be liberated and the italians were fed up with Mussolini by the time the americans landed on Italy and on both situations they didn't face extensive civilian resistance but many civilians actually help the americans and the soldiers felt symphaty for the people on those countries because no massive numbers of american civilians were being slaughtered.
On Russia, the thing was different, the russians passed through an holocaust of epic proportions, one day a civilian saw their relatives being murdered by the germans on the next day now drafted on the army, it was hard to see things on an objective way, many thought on payback and many on positions of command too. You have to keep in mind too that there were this trauma on Russia at that time and any narrative that tried to paint the germans as the good guys wouldn't fly, this obviously ignoring there is no free press on war (and even afterwards on Soviet Union).
On the case of Japan, the americans had more reason to be hostile with the japanese, but the country had already given up by the time the americans landed on it, it there was a gruesome battle that took years on japan, thisgs would change of figure. The attack o Pearl Harbor was a military target attack, the american pride was hurt but not millions of soldiers and civilians over years with the threat of the destruction of the whole nation.
To make matters worse, the soviet army recieved orders from the soviet elite to turn the east european countries on communist countries by force, and this always fly well with the population and won't cause massive problems at all...
While there were war crimes on east germany, it is hard to know how much, there is always the accusation but I don't think it was nowhere close to what the japanese did on China that the chinese goverment is still hostile with Japan all those years. I don't see Germany with the same level of hostility towards Russia, maybe the germans are quiet about this... I dunno.