I worked for a Japanese company a number of years ago. The Japanese who lived in the US got one heck of an education about WWII. There was one engineer close to my own age (mid twenties at the time) who honestly didn't know anything about Pearl Harbor, Midway, or any major battle in the Pacific.
He said that it was forbidden to talk about it back home, the shame and anger was to great.
Japan is a an intensely tribal, completely xenophobic, and very racist society. They are self-selected as a Master Race, in ways Goebbels might have wished he thought of!
I think you'll find the "shame" factor among the older generation that actually knows something of the war, is engendered by the fact that they lost. The "anger" comes in because, as Children of the Sun God, they think they did not really lose, and could have gone on fighting until they were either 'honorably' wiped out,which was the plan, or WE gave up.
These folks are actually very PO'd that we have America, and they don't.