This is a result of Japan's Imperial aggression in China, other parts of Asia and it's attack on Pearl Harbor.
And, horrible as it is, it pales compared to the damage and destruction that Japan wreaked on the world during it's failed bid for Global Domination.
Japan caused 100% of it's own suffering.
Also, Japan's treatment and resultant success after the war was a result of it's treatment by the victors.
This treatment was 180 degrees from how Japan treated those under it's control while (temporarily) victorious.
Hey Japan, there is such a thing as Cause & Effect.
Learn it. Live it. Love it.
It is a shame, though,...that they did it to themselves.
No matter what happened between warring countries, you cannot be okay with the suffering of civilians just living their lives, right?