Sooo, putting them on reservations? Oh shit, that's been done also. I'll have to work on something more modern.
You're looking at history through todays distorted lens.
Had the Euros not raped and pillaged, another advanced civilization would have, probably the Chinese.
The bottom line this is how hunanity has always worked, and in this case there's no way an advanced culture would have ignored this continent and not sought out it's riches.
You can spit on these people all you want, but the truth is this is how it's always been. The top dogs grabbed for the brass ring.