My grandparents are still rather bitter about the Japanese as well and less so about the Germans...but I don't share the sentiment. (They rarely say anything bad about Japan, but long ago when I started buying Japanese cars and trucks and shunned the shoddy stuff the "Big 3" were putting out, they weren't terribly happy over it. Probably didn't help that one branch of the family worked for Ford.)

An irony about WWII: My grandparents and their siblings were Great Depression children and very nearly starved in the U.S. One set of clothes, not much to eat, working hard as children to raise a few cents a week for food. So while much of the rest of the world suffered horribly through the various ravages of war, things actually improved for them (although they wouldn't describe it that way.)