NEW RULE. To follow up on Matt's spat with David Frum, I think a rule needs to be adopted: If you don't care about income inequality normally, you're not allowed to make it your central argument against immigration. Frum is a guy who, throughout his career, has argued that income inequality has simply been a surge of salaries at the top. And he's been similarly unconcerned about mobility (which has decreased across the board, not just for Mexicans). The rich get richer, but the poor don't get poorer, so why worry? And to show how attentive he's been to the issue, searches on his blog for "inequality" or "mobility" turn up, literally, nothing. But when the subject turns to immigration, both become issues of paramount importance.

Last night, over drinks at the Rooster, we were talking about what separated intellectual dishonesty from simple dishonesty. And this is an excellent example. Frum's arguments on intergenerational wage convergence among Latinos aren't lies. So far as I can tell, and my read was admittedly quick, they're perfectly true. But Frum isn't a guy who cares about intergenerational wage convergence, or equality of incomes -- he's dishonest in his concern. He may worry about what low incomes or poor educational attainment are correlated with, but he's curiously unwilling to make that connection explicit. To be fair, though, Frum isn't the only, or even the worst, offender. That comes in the right's widespread adoption of George Borjas's work, which I say more on here.

--Ezra Klein