The point is that the factors that led to these crimes are all still there. Were the circumstances to arise again there is scarce doubt history would rhyme or repeat.
US is still in Irak now... It's really not hard to find where the US is military active.
The US jail population is 2 M, China, 1.5 M. It's little stuff like this that make the US look worse than China.
Be sure that once China is finished killing Uyghur they will say that's an old story like ... hum ... the US. So yeah continue justify crimes, just remember one day, it could be your turn.
The systems that committed those injustices and crimes against humanity are alive and kicking. The processes and motivations that led to those matters are still present. The only thing that changed is that there is no more motivation to commit such atrocities again, surely those will come back.
Beyond that, I don't see why we should excuse past crimes. All that motivates is for future crimes to be done faster so that the moral high ground can be restored then.
So if only now matter you mean that nobody should pay their debt? Cause i know a country who goes to extreme length to get back his money... So which was in it? Both ways i guess.
By the way if you interested the US is STILL in Irak, Donald Trump PARDON the CEO of Blackwater, US is supporting the war in Yemen, look it up it goes on and on....