… is from page 403 of the 2016 second edition of Thomas Sowell’s Wealth, Poverty and Politics  (original emphasis):
The “legacy of slavery” argument is often presented as if to excuse bad behavior in black communities by depicting such behavior as results of the past sins of whites. But the “legacy of slavery” argument also serves as an exemption from scrutiny for counterproductive social trends in the wake of welfare state policies and the vision behind those policies. Tactically, these arguments have been very successful in a political sense. But, empirically, to say that a “legacy of slavery” has kept black communities from rising above their current level of behavior is to defy historical evidence that many black communities had a higher level of civilized behavior generations ago, before the triumph of the welfare state vision. Moreover, a very similar retrogression in the behavior of low-income whites in England, in the wake of very similar policies and visions there, suggests that similar policies and visions have produced very similar results on both sides of the Atlantic.