Donald Trump acknowledges photographers after speaking at a campaign rally in Baton Rouge, La., on Feb. 11. (Gerald Herbert/Associated Press)

When Donald Trump said a few weeks ago, “I could stand in the middle of Fifth Avenue and shoot somebody and I wouldn’t lose any voters,” he was probably right (depending on whom he shot, I suppose). Everything that was supposed to derail his candidacy has failed to do so, and if he wins Saturday’s South Carolina primary (where polls show him with a comfortable lead), there could be no stopping him. But in last Saturday’s debate, Trump said some shocking things, at least to Republican ears: Not only did he criticize George W. Bush for launching the Iraq War, he also said that Sept. 11 was Bush’s fault. And he did it at a time when the former president himself is finally emerging to campaign for his brother; W will be speaking at a rally for Jeb tonight.

Surely, Republicans might want to believe, this will not stand. There are some things you simply cannot say and retain the support of the Republican electorate. But don’t bet on it. In fact, I’m guessing this isn’t going to hurt Trump at all, because Republican voters’ feelings about Bush are, shall we saw, complicated.

If you missed the debate, the extended bickering about Iraq and 9/11 was truly remarkable. First Trump said that Bush lied to the public about Saddam Hussein having weapons of mass destruction, then he noted that Sept. 11 happened on Bush’s watch. First Jeb Bush and then Marco Rubio chimed in to say indignantly that Bush “kept us safe.” To which Trump replied, “I lost hundreds of friends. The World Trade Center came down during the reign of George Bush. He kept us safe? That is not safe.”

I would interject here that while 3,000 Americans were in fact killed here at home by jihadi terrorists during Bush’s time in office — you can look it up! — the total for Barack Obama’s presidency is 42, or an average of six per year. I expect that in the next debate, the Republican candidates will take the time to praise Obama for the extraordinary job he’s done in keeping us safe.

In any case, it’s important to remember that Republican dogma on this question is clear: Bush had zero, repeat, zero responsibility for the Sept. 11 attacks. There was nothing he could have done at all. When they talk about it, you’d think Bush took the oath of office on Sept. 10, 2001. The only thing that’s even worth discussing on that topic is how heroic he was afterward, and there’s no question that “he kept us safe.”

But that’s only part of the story. First, on Iraq, the consensus even within the Republican Party has become that the war was indeed a mistake. You’ll recall what a difficult time Jeb Bush had when he was asked whether he agreed with that, and by the time he finally said yes, most of the other candidates had said the same thing. Even if none of them would go as far as Trump to say that Bush lied about WMDs, criticizing the war is not going to get Trump in too much trouble with Republican voters.

And then there’s the fact that on the broader subject of George W. Bush, Republicans are torn. Something curious happened after Bush left office with approval ratings in the low 30s: The Republicans who had remained so loyal to him throughout his presidency began saying that they never really liked him anyway, and that he wasn’t a real conservative because he increased the deficit (despite their lack of concern for the deficit while they were applauding the tax cuts and wars that made it balloon). Even though Bush’s approval ratings among Republicans have come back up over time, he’s no Ronald Reagan when it comes to universal Republican esteem.

Donald Trump also has a latitude for ideological heresy that none of the other candidates are granted. That’s not only because his appeal has nothing to do with fealty to conservative ideology, but also because Trump’s voters have already been through this kind of controversy before and stuck with him. They’re used to performing a certain kind of rationalization, which goes like this: Sure, I didn’t really like that one thing he said — maybe it was his criticism of Megyn Kelly, or maybe it was the one about John McCain not being a real hero — but I love that he says whatever he wants without caring who he offends. That’s at the core of Trump’s brand, and it inoculates him from being punished too harshly for any particular statement.

Furthermore, Trump has some room to maneuver on questions like this because he’s positioned himself as the most butt-kickin’-est candidate when it comes to terrorism and the Middle East. It’s one thing for some wimpy liberal to say that Bush should have done more to stop 9/11, but it sounds different coming from a guy whose approach to the Islamic State is to bomb ’em all to hell and take their oil. It sounds like Trump is being iconoclastic and bold, just like always, even if you don’t agree with him about this. And let’s not forget that Trump still doesn’t need to hold a majority of Republican voters, just a plurality, which he’s doing with room to spare.

All of that means that, once again, some Republicans will say, “This time he’s gone too far!” And the people supporting Trump will keep cheering.