This history should have served to temper expectations for the first black president. Without taking away anything from Barack Obama’s historic accomplishment, or the country’s widespread sense of pride in the racial progress that his election symbolized, the reality is that there was little reason to believe that a black president was the answer to racial inequities or the problems of the black poor.

The proliferation of black politicians in recent decades — which now includes a twice-elected black president — has done little to narrow racial gaps in employment, income, homeownership, academic achievement and other areas.

Most groups in America and elsewhere who have risen economically have done so with little or no political influence, and groups that have enjoyed early political success have tended to rise more slowly.

“Group cohesion, expressed in political pressure and bloc voting, is often regarded as axiomatically the most effective method of promoting group progress,” explains the economist Thomas Sowell.