[L]eaving home is hard, and the social distance of wealth makes it even harder. [...] Just a quick comparison of black and white neighborhoods is enough to illustrate the particular challenges that face black families as they reach for middle class, or try to keep their position. The key fact is this: Even after you adjust for income and education, black Americans are more likely than any other group to live in neighborhoods with substantial pockets of poverty. [...] Black Americans live with a level of poverty that is simply unknown to the vast majority of whites. It’s tempting to attribute this to the income disparity between blacks and whites. Since blacks are more likely to be poor, it stands to reason that they’re more likely to live in poor neighborhoods. But the fact of large-scale neighborhood poverty holds true for higher-income black Americans as well.