Charles Murray is the most interesting and provocative of our political demographer-sociologists (a mouthful, isn't it?). I've read several reviews of Murray's new book Coming Apart but the Jonathan Rauch review in reason.com is by far the best. I recommend it to you.
I believe Rauch identifies an important shortcoming of Murray's work in the review's final couple of paragraphs. Murray doesn't talk about the middle 50% of the population, and that's where much U.S. social mobility occurs.
Many people reading this blog are examples of mobility from the lower middle class to the middle and upper middle classes. As we know, that achievement is far from trivial. We're not Masters of the Universe, we still shop at WalMart, but we travel overseas and earn graduate degrees, too.