The letter was good. I grew up in Detroit, in a mixed neighborhood, got along well with our black neighbors (back then "black was beautiful"). I don't know if we had "white privilege" very much, as we were an ethnic minority ourselves, and honestly, I was rather young. Still, I can see that it was there.
I am quite perturbed by what I see in the US these days, from a distance ( I moved to Israel over 30 years ago). I do not believe in fast, easy solutions to these kinds of social problems- but it has been going on in one form or another for many generations.
I am also disappointed in Mr. Obama. I think that he has, or could have, a historic role in this regard. He should have flown to some of these trouble spots, like Ferguson, as a symbolic gesture to help calm things down.
edit: I have been thinking about it, and we did have a Black maid. I know my mother was very friendly with her, and kept in touch with her for decades after she stopped working for us- but nobody I knew had a white maid. There was a book or movie about that recently.