Assimilation on steroids.

In their on-line coverage of their on-air coverage of the 300-million mark reached by the U.S. population last week, the editors of The News Hour did not highlight what may have been the most important point of all.

They did have the good sense to interview Brookings' Bill Frey and he had many interesting things to say. Among them was the thought that when we reach 400-million (in as little as 37 years), inter-ethnic marriage and coupling will likely have become so extensive as to wipe out (not his words) today's obsessions with race. How lovely.

Becker and Posner do the usual fine job of weighing the many sides of population growth. But they too miss Frey's big point. Politics alone creates many problems but it becomes poison when it mixes with race.

Most countries have their own peculiar histories of racial strife and the U.S. is no exception. But assimilation has always been the most promising antidote -- and intermarriage between the races and ethnicities on a scale where the tired old categories fade is assimilation on steroids.