I am white but I have been told by my (Taiwanese) manager that, "All Asian's hate the Japanese." I know only a little of the history of Japan and its neighbors

I am white but I have been told by my (Taiwanese) manager that, "All Asian's hate the Japanese." I know only a little of the history of Japan and its neighbors but he assured me there is a long history of Japan being the aggressor behind this sentiment. I don't feel like I'm trying to paint you in a bad light, rather hoping you'll concede that one side doesn't get a free pass if the other does something atrocious. Perhaps it was my having been raised a Quaker during a formative period of my life, but an eye for an eye is quite the opposite of my philosophy.