David Blakeslee….. I believe the effect of Native American Boarding schools cannot be considered as “either good or bad” in any monolithic way.

I have heard from or spoken with Native Americans who were of my parents age in Oklahoma, Arizona, and the Dakotas and all were equal in their condemnation of boarding schools. It was for them as if they were being orphaned from their parents. And the cultural loss was significant. I remember hearing from the Catholic Benedictine fathers from my home in Indiana speaking highly of their school in the Dakotas and yet later hearing horror stories from those who attended their schools.
There is much that is done in the making of this country which one would rather have been done differently. More often than not that occurred after the cessation of hostiliities. However, there comes a point when one has to simply put it aside and realize that this continent, this country, was fought for and won. Or as Spike, an English vampire, on Buffy the Vampire Slayer once said:

I just can’t take all this mamby-pamby boo-hooing about the bloody indians. …. You won. All right? You came in and you killed them and you took their land. That’s what conquering nations do. It’s what caesar did, and he’s not going around saying, “I came, I conquered, I felt really bad about it.” The history of the world isn’t people making friends. You had better weapons, and you massacred them. End of story.

Well, maybe not perfect but somewhat in that vein.