Why did the pardon-war-criminals movement succeed in Japan but not Germany?

Alright OP, I've found a thread for you dealing with specifically Unit 731. I will warn you not to read too widely on what they did if you are prone to a queasy stomach (there are pictures, videos, etc). I've highlighted some of the good reasons I found in there.

/u/TectonicWafer writes:

There's a famous book I read some years ago entitled something like Race and War in the Pacific. One of the authors main points was that because of how the Americans viewed the Japanese as a racial "Other", the Japanese leadership and population was implicitly and explicitly held to a different moral and behavioral standard than were the Germans. In essence, the Allies were more genuinely shocked and outraged by German atrocities because the Germans were fellow white Christians, and were therefore expected to know better. Whereas in the case of the Japanese, they were a bunch of Asiatic savages who were merely reveling there pretenses to civilization. Obviously, there are a fricking boatload of deeply racist assumptions behind this line of reasoning that far better scholars than I have spent the last 70 years trying to unpack and understand.

The book referenced is actually War Without Mercy; Race and Power in the Pacific by John Dower.

/u/feelslikemagic writes:

It is also worth noting that the pool of Germans responsible for the worst of the war crimes was relatively small. If the same standard of justice had been enforced in the Pacific Theatre, the Allies would have been faced with prospect of executing tens of thousands of Japanese. More importantly, those Japanese who were tried and executed became symbols. Some, including Yamashita and Homma, were arguably good and honourable soldiers, yet they presided over regimes of unspeakable cruelty. Put another way, hanging a few generals was far more appealing than trying, convicting, and executing tens of thousands of soldiers guilty of committing atrocities. This was not the case in Germany, where many of those responsible for individual acts of cruelty paid with their lives. In Nemesis, Max Hastings writes:

In 1945-46 some Japanese were prosecuted for war crimes. To impose retribution on all those guilty of barbarous acts would have required tens of thousands of executions, for which the Allies lacked stomach. Very few Japanese were called to account for their deeds in China and South-East Asia. The US, dominant partner in the alliance, focused its vengeance against those who committed atrocities against white men and US colonial subjects.

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