Do Japanese really support war over China/Taiwan?! I went to Japan to ask.
I solely believe that for China and Japan to have a good relationship is to do what United States did towards Japan by beating the sense out of it.
The Perry expedition during 1850s has ended Japan's roughly 200 years of isolation and open up trade with western powers through gunboat diplomacy.
At the near end of World War II, the atomic bombing of Hiroshima and Nagasaki brought an end to the brutal war which afterwards Japan became sidekick for the US kinda like Batman and Robin.
If China really want some respect from Japan, they need to deal significant damage towards its economy and exert dominance on most industry to the point where Japan no longer has the will to compete with China in most areas leaving only a few such as animation and gaming for Japan to remain somewhat relevant for future generations.