Is it legal to conquer and annex a rich and strategically valuable country with lots of resources if it has slavery or other bad practices (based off your opinion) and you want to free the people and make them your own
You are doing no different than invading another country at that point. It was 75 years ago. The vast majority of people of Tibet never lived before China took over.
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Anonymous#14d
The full majority of native people living in Hawaii and Puerto Rico were born in the US