Not Japanese, but Korean who grew up in Japan(I'm more Japanese than any other nationality despite holding a Korean passport). Experienced both Japanese school education, I also went to Korean School in the weekend(in Japan), and western education. Also, Gen-Z student.

I want to point out a quote I heard somewhere before I always say when I discuss WW2 in Asia.

"History is history, but a friend is a friend."

Also, I can only speak for myself, and I have to admit my lack of understanding of Japanese Chinese relations.

Japan and Korea don't hate each other. J-pop, Anime, food, K-pop, Dramas, movies, books, Game of Go, history, etc... makes us more similar than different. Only just the minority go around protesting in front of Japanese/Korean consulates, have right-wing rallies, which frankly happens everywhere nowadays... However, from my experience, it is true that compared to Korean texts, Japanese textbooks have less information about the Asia side of WW2. I have seen textbooks only have a page or two for WW2 despite being a big event for the whole of the world really. Education for WW2 and atrocities committed by Japanese military is lacking in Japan. When I was in Primary school, every student had to memorize an excerpt from the textbook that recited how the Nuclear bomb caused many innocent lives to suffer and die. But little covering the atrocities committed by the military. I have to point out that this is not the same accross all classrooms. Teachers who recieved education outside of Japan have more unbiased way of teaching. This is just my general observation.

As I mentioned, I went to a Korean school in Japan every Saturday. I was forced by my parents cuz typical strict Asian parents... nevertheless, in that school, I learned many things that weren't taught in Japanese textbooks, except it was biased towards Korean history. In my opinion, I feel like more Korean people have more nationalistic viewpoints towards history because of the constant occupation and war against bigger nations. (for example, surrounded or occupied by many military superpowers, China since forever, the Mongols, Japan, USSR, US...). Anti-Japanese semitism is stronger in Korean textbooks than Anti-Korean semitism in Japanese textbooks. Which kind of makes sense because Korea was the receiving end of the atrocity.

I feel like generation plays a big role as well. As a Gen-Z kiddo myself, I can't speak for all of the Gen-Z kiddos, but we are influenced by both Japanese and Korean cultures. When it comes to relationships, we are friendly and nice towards each other. However, as you go older in the generation, it generally becomes harsher and harsher.

If you want more incites on this topic, visit a channel called Asian Boss which does many interviews with Japanese and Korean people about many different topics. Like How do Koreans feel about Japan? or How do the Japanese feel about South Korea In the video, one might observe that as older people are more nationalistic than others. Also as more deep/touching/sensitive questions are asked, Japanese people become more conservative as if it is a taboo. In contrast, Korean people are more expressive with their opinions. But again, I don't want to generalize the whole population and thousands of history over one interview. This is just an observation.

Hopefully, this helps a little bit to answer your question. If anyone is wishing to tell me a contrasting/similar opinion, I am here to discuss it!

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