What’s interesting isn’t that he’s still not sold on the legitimacy of Obama’s birth certificate but that he doesn’t want to talk about it anymore. That’s a concession, I guess, to the fact that in a field as divided as this one, with all the attention he’s getting, he’s a marginally more serious candidate than he would have been four years ago when he was all birther, all the time. No sense alienating anyone who likes the fact that he’s willing to talk about crimes committed by illegals but might waver if they see him wandering off into conspiracy theories.

Then again, how many people are there in that category? The whole appeal of Trump is that he says things that irritate the ruling class (of which he’s a part, but never mind that), and nothing irritates them more than questioning Obama’s origins. That’s why it’s silly for critics, myself included, to grumble about all the donations Trump’s made to liberals over the years or how highly he’s spoken of Hillary Clinton in the past or how he used to be pro-choice and supported universal health care as an entitlement. Reminding voters that he’s not remotely a “true conservative” might hold his numbers down but it’s not causing him to lose any support among people who are already onboard, because whether he’s conservative or not is beside the point. He irritates the people who irritate grassroots conservatives and that’s close enough to “conservative” to count, I guess. Ace explained that dynamic yesterday in terms of class: The GOP is essentially a coalition of an urban, centrist professional class (what he calls the “comfortable” class) that’s culturally aligned with the left and a more blue-collar, populist working class that’s firmly right-wing, and neither one can stand the other. Even if Trump’s a phony in his principles — three years ago, he knocked the party for being too harsh(!) in its rhetoric about illegals — the fact that he’s antagonizing the comfortable class on a subject on which they’ve failed the working class again and again makes him an honorary “true conservative” if not an actual one, right? That’s why Trump gets a pass from tea partiers for ideological heresies that would have made Mitt Romney blush at their RINO impurity. He’s being “purified” by combat. The more heat he takes, the more sponsors he loses, the more of a “warrior” he is, the more his sins can be overlooked. (I’m actually morbidly curious to see how much support it would cost him if he turned around and endorsed a core Democratic policy. Some would be dealbreakers, like a handgun ban, but I wonder if he could get away with backing, say, legal abortion for the first 12 weeks and still retain the 10-15 percent of Republicans he has now.) This is why I’m surprised he’s toning down the birther stuff: It’s pure “warrior” signaling to his fans, proof that he’s willing to extend a middle finger to Obama that no other Republican will. If anything, doing it might buy him a little extra credit with them so that they’ll let him get away with expanding Medicaid or whatever.

Anyway, hopefully some more electable GOPer will begin reminding Latino voters that if they object to what Trump said about rapists from Mexico because it lumps innocent people in with bad actors, they shouldn’t make the same mistake themselves by holding all Republicans responsible for Trump’s pronouncements. If they do, that could be especially bad news at the Senate level, where states like Florida and Colorado with large Latino populations may well decide who holds the Senate in 2017. Republicans in Colorado are already nervous. Exit question: Is it true, as Trump claims, that McCain was a birther in 2008? I understand the knock on Hillary, who famously said that Obama wasn’t a Muslim “as far as I know,” but McCain was the guy who wouldn’t even let his surrogates talk about Jeremiah Wright for fear that it’d be racially incendiary. What would he want with Obama’s birth certificate?

Update: One more point about why the Trump boomlet is so fascinating. For years, the knock on tea partiers has been that they hold Republican politicians to unrealistically high standards of purity. One ideological misstep, the narrative goes, and you’re apt to be cast out of the movement. The bar to qualify as a “true conservative” is fantastically high. What Trump proves is that the bar is actually shockingly low, provided that the tea party’s critics seem to disdain the pol in question as much as they do conservatives. RINOs hate Trump almost to a man, ergo Trump must be doing something right. His points of ideological agreement with conservatives, like on immigration, prove that he’s a member of the movement in spirit notwithstanding his many, many previous points of departure.