The happy talkers tell us that diversity is a boon, making our society stronger and better. Our own lying eyes tell us that it is the source of continual trouble; not merely the solitary "hunkering down" that Robert Putnam discovered, but rancor, disorder, litigation, and violence.
Once this was a nation of farmers, builders, inventors, creators, explorers, and thinkers. Now we are a nation of bubblehead academic poseurs, race-guilt hucksters, and keening middle-class "victims" of imaginary wrongs.
Most people are not intellectuals — a fact that intellectuals have terrible trouble coming to terms with.