Well if looking at the actual history, its not black and white good vs bad like with Nazi Germany in Europe. It's a big blur of grey. It is actually more on the US and China side to recognize yhe gray of it instead continuing to indulge in being on the right side of what they've been conditioned into believeing it having been a black and white/good vs bad like in Europe.
Again, it's nothing but Japanese short-sightedness and foolish arrogance. You can ignore me, but I will carry on with my point.
In terms of real repentance, the Japanese actually repented much more completely than the Germans. The Japanese people today truly believe in peace, caring for people, equality and human rights. Germans, on the other hand, still has that same arrogance and ubermensch attitude deep down.
However, the Germans are cunning enough to not be foolish like the Japanese. The German actively beat their Nazi-past as a sandbag, and use that to gain legitimacy and moral superiority over even those true defeater of NAZI germany (namely the USSR, the USA and Russia). They use this moral high ground as a diplomatic-political leverage to exert power far beyond their borders.
The Japanese did none of that. All they ever did is doing business and care little about playing the political game abroad. And now that their economic power is no longer a dominant force in the world, they left behind nothing in the diplomatic-political realm. Yes, sure, the majority of Japanese are happy about their non-expanding, passive and inward-going attitude. But that is NOT a good thing for Japan.
The Japanese need to be active, aggressive, outward-going, and take this chance to take a lead in Asia, before it's too late. If the Japanese believe in their values, then be a blameless champion for their own pacifist modern culture and expand that into the political diplomatic realm.
Sacrifice is necessary, especially those dead war criminals. All you need to do is to move those couple of handful names plates out of the Shrine, and you would have gained an immensely large leverage, this will give you a moral high ground you would never imagine.