Another Japanese society, another time. Yes....Japan did commit some heinous actions in that war. A war they ultimately lost. The emperor was deposed, and Japan was reorganized as a republic.
In the end, the Japanese DID learn the answer to world peace (despite their racism). It's profit.
Instead of remaining a violent society, they learned how to compete economically, and succeeded.
Do not blame yesterday's people on today's. That's a presentism fallacy.
Leopards never change their spots. They're just wealthier leopards now.
They hate each other as much as the French and the Germans do! And for much of the same reasons!