The very week that the Republican presidential field insisted that the economy is great, we need more tax cuts for the rich, and that Americans who feel left behind really have nothing to complain about, we see yet another report about the stunning gap in income inequality.

The richest Americans’ share of national income has hit a postwar record, surpassing the highs reached in the 1990s bull market, and underlining the divergence of economic fortunes blamed for fueling anxiety among American workers. […]

The IRS data go back only to 1986, but academic research suggests the rich last had this high a share of total income in the 1920s.

Asked about the growing gap between rich and poor, the president said, “[O]ur society has had income inequality for a long time.” How insightful.