Germany has done all it can and more to erase the stigma surrounding it's wrong doing in the war, they've apologized, made memorials, basically admitted they were wrong, formally apologized and did what they could to make it right and move on.
Japan on the other hand, all these years later still can seem to swallow their pride enough to just say, "we were wrong and we're sorry". That's all anybody is asking for. To try and get around that and all these years later still try to cover it up and deny it shows not only a lack of respect towards the victims but also true cowardice on their part.
Germany did do the worst crimes, by far, and it stuck, but at least they had the good grace to suck it up and say sorry.