Sowell lays it out
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: "Slavery also cannot explain the difference between American blacks and West Indian blacks living in the United States because the ancestors of both were enslaved. When race, racism, and slavery all fail the empirical test, what is left?
Culture is left.
The culture of the people who were called 'rednecks' and 'crackers' before they ever got on the boats to cross the Atlantic was a culture that produced far lower levels of intellectual and economic achievement, as well as far higher levels of violence and sexual promiscuity. That culture had its own way of talking, not only in the pronunciation of particular words but also in a loud, dramatic style of oratory with vivid imagery, repetitive phrases and repetitive cadences.
Although that style originated on the other side of the Atlantic in centuries past, it became for generations the style of both religious oratory and political oratory among Southern whites and among Southern blacks--not only in the South but in the Northern ghettos in which Southern blacks settled. It was a style used by Southern white politicians in the era of Jim Crow and later by black civil rights leaders fighting Jim Crow. Martin Luther King's famous speech at the Lincoln Memorial in 1963 was a classic example of that style.
While a third of the white population of the U.S. lived within the redneck culture, more than 90% of the black population did. Although that culture eroded away over the generations, it did so at different rates in different places and among different people. It eroded away much faster in Britain than in the U.S. and somewhat faster among Southern whites than among Southern blacks, who had fewer opportunities for education or for the rewards that came with escape from that counterproductive culture.
Nevertheless the process took a long time. As late as the First World War, white soldiers from Georgia, Arkansas, Kentucky and Mississippi scored lower on mental "