Japan still needs to work out its role in WW2.
In a sense, they have, and that's the problem. To be born in Asia, prior to WW2, was to be born chattel. It was sometimes implicit, and sometimes literal, but for every Asian country save Japan it was universally true. To be Asian was to be considered inferior. But Japan was in a position to do something about that. World War 2 in the Pacific, in a very real way, happened because Japan was seizing the opportunity to strike at those who had oppressed the region for generations.
Japan cast itself as liberator from white imperialism. It is the only war goal that Japan can be said to have actually achieved. By their victories in World War 2 they irrevocably destroyed the legitimacy of the colonial powers in Asia and freed an entire continent from western imperialism. To the Japanese mindset, which often values the integrity of the act more than the outcome of it, that cloak of purpose is what truly matters. This is at the heart of their inability examine their own actions during WW2 with anything like the seriousness their victims typically feel is necessary.