Earlier quoted context omitted.
Where and how did I do that? All I am saying is that us Humans are a vicious bunch. I have no illusions that Indians would have slaughtered Europeans if they had the means to do so. If Dutch didn't buy slaves, they would die working for someone else. Was Japanese military and economic oppression merely an attempt to dethrone The White Man(tm) as chairman of hell? What if Mongols had managed to get their act together?…
The fact that you can imagine hypothetical situations where the oppressed was the oppressor, or was oppressed by others, doesn't excuse the actions taken by their actual oppressor. "...us Humans are a vicious bunch" is merely a statement, not a valid excuse.
If I understand your position:
1. Occupation, slavery and aggression were parts of most/many historic societies.
2. Just because a behaviour is universal among human societies at the time doesn't stop you from judging a subset of the societies that committed them. (I seldom see condemnation of Arab slavery for sexual purposes etc.)
3. As a bit of extra humour -- the societies you condemn are the ones that did most for finally lifting the standard for human behaviour and implementing real rule of law!
(I might add that some societies would, given the opportunities, probably still act in similar ways. No condemnation from you, of course...)
Edit: Clarity