It's a cultural thing, they don't forget. Their governments probably hammer the history lessons home pretty hard.

I deal with it all the time. When we do military exercises with the Japanese and the RoK we have to keep them at arms length from each other.

But if you think that's bad...the Arabs are still butt hurt about the crusades. I mean literally every Arab with a 3rd grade education knows all about it and
lives it every day (you've probably never even heard of the crusades, it was about 1000 years ago).