A South Korean's view:

That's an interesting take but I cannot agree with 
what you say about South Korea and Japan. It is 
not well-known in the West (I did not know it until 
I came here, I am sorry to say) is that Japan 
occupied South Korea from about 1910 to 1945. It 
was a very brutal occupation - some of the 
detention centres still exist as museums and they 
are nightmarish. The Korean language was 
outlawed and a lot of books were burned. There 
was also a train line built across the country to 
move military supplies for the invasion of China, 
using forced Korean labour. Some parts of that line 
still exist as monuments - there is a section not far 
from me. This went on until the Japanese 
surrender in 1945; the Korean Independence Day 
actually marks independence from Japan. So, no, I 
do not agree that the Japanese were somehow 
trying to free Asia from European colonisation. 
Not around here they weren't, and I don't believe 
it in relation to the invasion of China either. And of 
course the 'comfort women' was a tragedy and an 
atrocity all its own. As for the Korean war, I spent 
some time with my partner's father, who was a 
military officer during the war. He has passed now 
but he had many stories to tell and he was glad to 
share them. I did not entirely believe them all but, 
like most people of his generation that I have met, 
he was profoundly grateful to the Americans. I am 
not aware of any massacres of South Koreans by 
American or other foreign troops, and I think he 
would have mentioned it.

An Asian's view based on Asian perspective:             
I spent 20 years to rewrite Asia History, and spent 5 
years t find that I will never overcome the award 
winning propaganda film coming out of Hollywood and 
the two abombs dropped in Japan and the 100 years of 
media monopoly by the West.
For example, do you know the Western version of the 
"madame butterfly" was more brutal than the their 
Asian version of the "comfort women".  Mass suicides 
of Asian women were frequent just to avoid being 
molested by Western troops.
Same could be said of the Japanese occupation of Korea 
and China.  Comparatively speaking, Japan was trying to 
unify, thus protecting, fellow Asians, while the West 
was colonization.  And the "Tanaka Memorial" that the 
West used to poison the bloods between Chinese and 
Japanese people in 1927 was a forgery.
You Japanese and Koreans were fortunate that, at least, 
you culture was majorly preserved.  In China, starting 
with a Jewish scheme by no other than Karl Marx(this is 
only been dug up recently), then passed down to 
traitors like the Taiping Rebels, Sun Yat-sen and Chiang 
Kai-shek, all converted Christians, not only fatally 
crippled China militarily, but also used opium to destroy 
China's culture of feudalism by bring a living hell on 
earth from 1911 to 1949.
The Christians and Chiang kai-shek, each killed 100 
million Chinese, mostly blamed on the Qing Dynasty 
and the Japanese.  The descendants of these traitor are 
still blaming the China's savior, Mao 
Zedong(accomplished the mission impossible of ridding 
China of the opium addiction) of killing 100 million, as 
well as the major surrogates for America to divide 
Korea, Japan and China. The recent Hongkong riots 
should give Asians some idea of their latent potential.
As for Japan, in my decade of research, what I found is 
that the Japanese were just bunch of anti-
Christian(extermination of Christian in the mid 17th 
century) Buddhists.  The greatest harms they did in 
China(definitely also Korea) were by the young-turk 
Japanese officers(who actually had to assassinate the 
prime minister and the educational minister to force 
their view on Japan), who acted as the hatchetmen for 
the local traitor leaders, like China's Chiang Kai-shek.
You said "I do not agree that the Japanese were 
somehow trying to free Asia from European 
colonisation."  But just go through Wikipedia, you 
would find all the Asian colonies that got indepences 
was the time Japanese landed.  In China, Japan 
supported the only legitimate Qing Government, as well 
as the largest Nanking government of Wang Jingwei, 
which was really China's war-time government.
Also, one time I asked the Chinese National Coach for 
juniors, who had a lot contact with north Koreans, to 
help me with helping North Korea, he told me bluntly 
that the Koreans used to be know in China as the "Little 
Japanese", since they were a significant part of 
Japanese occupation in China.
Then my Korean ethnic friends in Yanji, China, told me 
that the pro-Japanese Koreans, mostly shifted their 
allegiance to the America, after both the north and 
south Koreans rose to fight for independence.  The 
purge and destruction by America and pro-America 
Koreans in the South was no less than that's in the 
North, where each man, woman and child got 1.5 
incineration bombs per person.
Although, wiki easily watered down the massacre at 
Jesu Island by calling it an uprising and by communists, 
this was the standard practice by America everywhere 
in the world.  You see, they have been very successful 
going by the principal of "dead men cant talk".(kind like 
what Trump is relying on in his killing of old guys like 
me in the ongoing Covid-19).  And what we Asians are 
stucked with are the American Asian proxies, like your 
partner's father, who talk loud and heroically , and 
often with good pay.