Romney in particular should have learned from his own baleful experience, as he wasted millions in Iowa last time trying to clobber his rival Mike Huckabee as “soft” on illegal immigration. He attacked the former Arkansas governor in commercials and televised debates for once supporting a proposal, ultimately defeated in the legislature, for in-state tuition breaks for children who had been brought to the country without authorization. Though he outspent his opponent by a ratio of 10 to 1, the former Massachusetts governor lost badly in Iowa, 34 percent to 25 percent. It makes no sense at all for Romney, a vastly improved candidate in most other respects, to use the same feeble issue as a club against Perry, who’s doing a fine job clubbing himself with his endless series of verbal gaffes. Even on an ideological basis, the whole question of in-state tuition is unequivocally a state issue and not a federal matter for any prospective president to decide.

The current immigration fixation on the campaign trail not only steals attention from vastly more significant and viable themes, such as job creation and runaway federal spending, but also makes the Republican Party look deeply divided and hopelessly out of touch with mainstream concerns. Aside from the embarrassing discussion about Romney’s lawn-care service, the candidates don’t really differ on immigration policy. The next time one of the leading contenders gets a question or a challenge on the subject, the right response would be to emphasize that agreement. It’s easy to imagine Romney, Cain, Perry, Michele Bachmann, Newt Gingrich, Jon Huntsman, or even Ron Paul, if not Rick Santorum, affirming a clear and unanimous—and, one hopes, sane—Republican approach.