On Monday, Donald Trump said another of those Things That Must Never Be Said, thus supposedly dooming his presidential candidacy. Back in my younger, more naive days — say, back in July — I might have believed that this truly does mean Trump is finished. Now I’m not so sure.

Yes, House Speaker Paul Ryan and a few other prominent Republicans have come out to strongly denounce Trump’s proposal to ban immigration to this country based on religion. Good for them. But the unfortunate truth is that Trump’s proposal is not as far from the conservative mainstream as some would like to believe.

Look at his fellow GOP candidates. Ben Carson, who says Muslims should be barred from the presidency because their faith contradicts the Constitution, wants every visitor to the United States monitored but “we do not and would not advocate being selective on one’s religion.”

Because apparently that would be wrong.

The hapless Jeb Bush, who has personally advocated accepting Christian Syrians while banning their Muslim counterparts, tut-tutted on Twitter that "Donald Trump is unhinged. His 'policy' proposals are not serious." Sen. Rand Paul's campaign suggested that Trump is merely following Paul's lead, which is actually true: Paul had earlier proposed an amendment that would prohibit all travel visas from some 30 Muslim countries. And Sen. Ted Cruz, that bold defender of American values, was one of 10 senators to vote in favor of Paul's amendment and has sponsored legislation of his own banning Syrian Muslim refugees. He now says blandly that Trump's policy "is not my policy."

But of course it is.

If Syrian Muslim families are too dangerous to be allowed to set foot on our soil even after a two-year vetting process — and that has become the GOP’s basic position as a party — by what peculiar logic are Iraqi Muslims or Turkish Muslims or Nigerian Muslims or Indonesian Muslims or even French Muslims any different? Hell, what makes American Muslims any different?

That’s basically the question that Trump has now posed to his fellow Republicans, and they have no real answer. They have no answer because every single one of the candidates mentioned above has in one way or another enthusiastically, publicly embraced the position that the 1.3 billion Muslims around the world must be judged not by their individual actions, statements or character but by the worst actions of the extremists who claim to share the same religion. They have deemed Muslims collectively guilty, as a religion, until they individually prove otherwise, and that assumption of guilt is so strong that it cannot be overcome even with a two-year grilling and investigation by U.S. authorities.

How is that different from the position taken by Trump?

So it’s going to be interesting to see how the Republican base responds. In a Rasmussen poll taken last month, 60 percent of likely voters and 82 percent of Republican voters said they oppose the settlement of Syrian refugees in their state. Some 65 percent of conservative voters believe that the correct number of immigrants from the Middle East — read, Muslims — is zero. Given all that, I’m not convinced that they’ll abandon a candidate who says that out loud.

If they don’t, then we’ll be staring at something ugly.