Before going to Uni, I was in a intentional school in Shanghai for a couple years, and their were a lot of Japanese students. I can tell you these over zealot Japanese are a minority, every nations has their crazy dipshi!ts but unfortunately their government might be overruned by crazy dipsh!ts because of ignorance and brainwashing.
If you go up to a Japanese and ask them about WW2 they will say they have no idea what happened and the reason why such a vast majority don't know about their history is because if the ordinary person in Japan knew the full extent of what Japan did in the past, it may cause a major sh!tstorm, because the ordinary Japanese isn't heartless but the people in charge on the other hand are. If the ordinary Japanese people knew, then patriotism would be at a all time low, if patriotism is low then Japan can't keep its face and be militaristic.
The people in power in Japan need to keep the ordinary Japanese ignorant of what happened so the Japanese government can garner support from the people to continue being militaristic against China and rewrite their history to show Japan as a nation of "saints".
It's like early America, the white people weren't naturally racist against other races, they were brought up to hate other races, which is the exact same thing happening in Japan. The young Japanese kids are being brought up with fabricated and distorted facts to hate the Chinese and Koreans.