David Frum is, in my view, correct about immigration policy. But good luck selling even moderate restrictionism to Republican Party “modernizers.” That’s not to say there aren’t good reasons for reform-minded Republicans to embrace such a position: it’s compatible with the goals of less income inequality, less cultural/linguistic balkanization, and less racial polarization. Unfortunately, it is also very easy for supporters of the Bush-McCain-Obama approach to immigration to demagogue the issue and in turn whip up the demagogues on the other side. It’s the kind of debate “modernizers” are temperamentally inclined to shy away from.  But perhaps I’ll be pleasantly surprised (though so far the comments don’t look that way).