Thanks for posting, jdg.
Charles Murray has a history of detailed research and publishing his findings regardless of the controversy.
Kennison hits the target here:
"the most useful strategy of all is to allow the laws of natural community organization to work again by ending the Drug War, the police war on poor citizens, the overregulation that makes it hard to start and keep a small business, and the paternalistic “assistance” that prevents natural formation of strong families."

Spot on and glaringly in our face [As Ben Carson keeps reiterating]: "His point in focusing on the white class structure is that black communities have been the canaries in the coal mine — more fragile and more urban, and therefore the first to be effected by the social welfare bureaucracies. Now the social pathologies that destroyed inner-city black communities are spreading to the rural and suburban lower classes — marriage rates dropping, children brought up poorly, gangs and the drug war creating social chaos. Progressive whites could pretend the black community was in trouble because not enough was being done, and racism — but when the rot spreads to every city and town, it’s impossible to explain it as the result of racism."