I think native culture has done better the past 50 years than the 50 years before that.  Realize that their group first experienced genocide, and then in modern times, forced assimilation.   The comparable event for your arriving Chinese friends would be to have their children taken from them on arrival and placed out of reach in special schools hundreds of miles away.   This wasn't anomalous for natives but standard practice.  Further, prohibit any cultural practices that they arrived with. How would your Chinese friends have done under such circumstances?  More recently the indigenous peoples in our country have received recognition as a culture, and granted (or seized) greater political autonomy.  There's still much ground to cover, and the answers aren't simple.