The Japanese were sadistic and brutal occupiers of any country they conquered.
For many years the Chinese who either experienced, or learned second-hand about, the atrocities the Japanese committed as occupiers of much of China from 1937 to 1945, absolutely hated the Japanese.
I know a Japanese lady whose grandmother and grandfather were stationed in Nanking as prison guards under the Imperial Japanese Army and she very is proud of them, laughs about it and ironically her last.two boyfriends were Mainland Chinese. In fact I have met other Japanese who feel that that the only thing wrong that the Japanese did was to lose WW2.
Shinzo Abe introduced very strict revisionist history which doesn’t mention much about Japanese history from 1895 to 1945.
The Japanese pysche remains heavily scarred to this day by the way that they had to surrender and lose WW2 by nuclear destruction and it is not lost on Japan that they remain the only nation to have been bombed by nuclear weapons.
The Koreans also suffered heavily with gruesome brutality under the Japanese after the annexation of the Korean Peninsula in 1910 until 1945 and the legacy in part is the North and South Korea armistice to this day. The destruction of Korea by Japan help to encourage the conditions that led up to the Korea War in 1953 . N. Korea is the ultimate Cold War relic, more so than Cuba and Japan today could have been the same if Stalin had his way .
And the Kim Dynasty has developed nuclear weapons for their survival realizing that it would deter an American invasion which is not lost on Iran. Iran will soon have enough weapons grade Uranium to make their own nuclear weapons.
In fact, Iran probably already has nuclear weapons capability which is known by Israel and America so that the current talks between Trump and Iran are maybe somewhat of a farce. An Iran with open nuclear weapons capability is a significant nonstarter towards Middle East and world stability. China and Russia have unofficial welcomed Iran to the nuclear club .