Good thing he made that statement at a location where the US had a culture war with the Sioux indians.
Actually the entire US nation killed Native American Indians and they lost their culture and no white people gave a shit.
Your ignorance of world history comes into focus, the vanquished have ALWAYS been displaced by the winner, often rather harshly too. Who do we have so many burned to the ground cities of the past, what happened to the cities of Athens, Troy, Rome, Jerusalem, Carthage and so on?
The only legitimate grievance todays American Indians have are to sue over Treaty violations of the past, of which they have won a few big settlements, that is an area they can invest in to help rebuild something from.
Yes the American Indians were mistreated for a long time, pushed into poor land quality reservations, treaty violations were common, but that was over 100 years ago, they should have learned to adapt to the reality they are in now, instead of wasting their time hating and pissing away their culture, yes they are slowly destroying themselves on alcohol and casino based economy. Their culture is dying out because they are too busy being like YOU, carry anger around and not develop into somebody who can live in peace.
It might surprise you that Trump didn't displace or kill the Indians, sorry to burst your playpen bubble.