Not a criticism you might expect from a Republican who’s notable for his loud-and-proud centrism (and who worked for Jeb’s brother in the White House, of course), but it’s less surprising than it might seem. Frum’s a lot like Mickey Kaus in opposing amnesty from the center-left, for fear of what a huge glut of cheap labor will do to middle-class wages. (Which is not to say that righties don’t share that concern, only that it’s one of several factors in the mix — a demand for law and order, worries about cultural assimilation, etc.) A key bit from his interview today with Laura Ingraham (which you can listen to here), keying off his new post at the Atlantic about whether Bush is a “Republican Obama”:

“Jeb and Obama have something very important in common. They are both people who had to build an identity for themselves. They rejected the identity they inherited and built their own mixed identity. It’s an almost kind of post-American identity. Immigration is a test and proof of their identity. Jeb Bush talks about his a lot—he talks about his family being bicultural. That’s the reason he moved to Miami. He didn’t want to live in a society that was monoculturally American. He wanted to live in a bicultural society so his children could be bilingual. But, one of the things that emerges is that he is very like Obama. He is not satisfied with America as he inherited it, and he talks a lot about how we can’t achieve prosperity merely with our existing demographics. That’s his phrase, “with our existing demographics.” He sort of suggests that it’s not just that Americans are too old, or that immigrants will lower the age of the population. That’s not true by the way. But he also seems to think that native-born Americans aren’t enterprising enough, aren’t energetic enough, don’t love their families enough. The solution, the way to repair the troubles of America is to change America through immigration by importing people who are somehow better than native-born

What he’s concerned about is that we can’t grow at 4 percent “with our existing demographics.” And he has said that immigrants create more jobs and build more businesses than the native born. Which used to be true, but isn’t true anymore. That they have larger families, that is true. That they’re going to save Social Security, and that’s really not true. And they’re certainly not going to save Medicare because this is a population that’s quite poor.

Fair cop? Bush will deny it emphatically, of course, but Frum’s right that his tone in discussing the economic glories of heavy immigration often seems qualitatively different even from other pro-amnesty Republicans. Someone like McCain or Marco Rubio will include the obligatory “nation of immigrants”/”shining city on a hill” rhetoric in their own statements, but they tend to focus on pragmatic arguments for amnesty — i.e. you’re not going to deport 11 million people so you might as well bite the bullet and solve this problem, whatever that might regrettably mean for rewarding lawbreaking. Bush, as Frum notes, tends to eschew the “if we must, we must” pragmatic approach in favor of a more effusive pro-immigration argument. To refresh your memory, here’s what he said about solving Detroit’s problems in the 2013 comments that were made public yesterday:

“It just seems to me that maybe if you open up our doors in a fair way and unleashed the spirit of peoples’ hard work, Detroit could become in really short order, one of the great American cities again,” Bush said then. “Now it would look different, it wouldn’t be Polish…But it would be just as powerful, just as exciting, just as dynamic. And that’s what immigration does and to be fearful of this, it just seems bizarre to me.”

You can’t expect Americans to rescue Detroit. For a heavy lift like that, we need the foreign-born. You’re comfortable installing a guy with a view like that in the White House as the last line of defense against the Democratic open-borders lobby, aren’t you? Here’s a snippet from his talk in Detroit yesterday about restoring American dynamism:

Bush said, “It seems to me we ought to be strategic about this about how do we create high, sustained economic growth And that is to shift away from family reunification being almost the sole driver of illegal immigration to narrowing that do what every other country has, spouse and minor children. And dramatically expanding immigrants that are coming to work. A  guest worker program to deal in the areas where there are shortages.”…

“Family formation rates in this country are at an all time low,” Bush continued. “Birth rates are below break-even. There are more single women than married women in this country for the first time in our history. Our demography could be huge strength for high sustained economic growth, or if we do nothing of it will end up becoming a significant problem.”

America’s economic engine can start roaring again, as we long as we don’t leave it to Americans to do it. This is the sort of the thing that’ll turn the race into a “Jeb vs. Not Jeb” question for the right if/when Bush breaks from the pack and establishes himself as a real threat for the nomination. But cheer up: It’s great news for Scott Walker and Marco Rubio, both of whom will have their own immigration sins largely expunged by wary righties in the name of stopping Bush once it comes to that.