His thesis is basically that America is going through an unprecedented divide between the working class and the upper middle class and that divide is likely to lead to the end of "the American Project," which is basically his term for the amorphous, shared set of American values. He focuses mainly on the change in four main areas: marriage, industriousness, honesty (crime), and religiosity, noting that these numbers have been headed in the wrong direction in working class communities, which leads to a lack of social trust, which, in turn, leads to a lack of social capital--basically civic duty. This is killing part of "the American Project." The best way to solve it is to glorify those working class Americans who buck the trend.
The upper middle class wields the other sword. This group, Murray says, has developed its own unique culture and has become increasingly isolated, choosing to live in "superzips" and not engaging with the rest of America. This has led to second and third generation upper tier Americans becoming increasingly ignorant to the problems and idiosyncrasies of the average American life because they don't experience it firsthand. Murray says those people need to "stop the obsessive search to be around others at the top of the socioeconomic ladder" and start getting involved with America again--particularly by extolling the practices they engage in (married before having children, hard work, no crime, higher religiosity), rather than saying it's OK for others to do what makes them comfortable.
I think Murray is right on a lot of accounts. And I think he's right that social forces outside of government are going to be the only driver for this--although I think the platform and "bully pulpit" the government provides is a great way of directing necessary social change. The bottom line though? He's right about the extreme divide.
I didn't grow up working class, but I have gone to school and worked with a lot of people from that background--and spent a significant portion of my life (lower middle class) closer to that end of the economic spectrum than the upper levels he contrasts them with. Since coming to Hamilton, where the majority of the community is in Murray's upper tiers, the divides are incredibly salient for me. I often feel as if I'm in two completely different worlds when I go back and forth from home and school. Honest confession, that, not the school work or snow, has been the biggest issue for me on the Hill. (#realtalk)
I don't agree with everything he puts forth--some of it has an authoritarian tinge to it in my mind--but the collapse of social institutions in the lower classes, and the increasing isolation--both conscious (such as vocation, school choice, and community) and subconscious--of the upper tiers of the middle class, are real, and potentially dangerous. He's drawing our attention to a really important issue, and we should all probably start listening. This is not something that will go away overnight--or quietly.