The Unconscious Oppression Of American Self-Sorting

"We are self-sorting, not only along racial lines but also along educational and income ones, particularly in our big cities. Our cities are increasingly becoming vast outposts of homogeneity and advantage, arcing ever upward, interspersed by deserts of despair, all of which produces in them some of the highest levels of income inequality ever seen in this country. Some call this progress; I call it a perversion, at least of the concept of diversity -- of race, culture, identity and class -- that dynamic engine that built urban identities and that is now being erased out of them." Charles M. Blow in The New York Times.