“Surely this time,” the establishment chorus cries with joy, “Donald Trump has gone too far!”

Sorry, but I wouldn’t bet on it.

What Trump did at Saturday night’s debate was ruder than any of his prior insults, profanities or remarks about women. He corrected the historical record about the 9/11 attacks, demolishing the fairy-tale version that has become a central tenet of Republican dogma. It’s true, and you can look it up: George W. Bush was president when the World Trade Center towers fell.

Trump went too far, of course, as he always does. He sought to actually blame the attacks on negligence by Bush and his administration. As I’ve argued in the past, terrorist atrocities should be blamed on the terrorists, not on the officials who try and sometimes fail to thwart them.

But historical fact is historical fact — except in polite GOP circles. After Trump committed his heresy, telling Jeb Bush that “the World Trade Center came down during your brother’s reign,” Marco Rubio quickly began an incantation of the Republican Creed: George W. Bush “kept us safe,” Rubio said, “and I am forever grateful for what he did for this country.”

Donald Trump just went after President George W. Bush – and Jeb Bush wasn't having it. (CBS)

When Trump claimed he lost “hundreds of friends” in the World Trade Center and said “that is not safe,” Rubio responded with another line in the GOP’s confession of faith: “The World Trade Center came down because Bill Clinton didn’t kill Osama bin Laden when he had the chance to kill him.”

There you have it, a great example of the made-up stories the GOP establishment tells to lull voters to sleep. It is strictly forbidden, Republicans insist, to suggest that Bush bears even the slightest responsibility for 9/11, though he was president at the time. But it is appropriate, perhaps even mandatory, to blame the whole thing on Bill Clinton, who had been out of office for nearly eight months.

And, of course, it’s fine to blame President Obama for any terrorist attack that happens anywhere in the world, since he is Evil Incarnate.

I disagree with Trump on almost everything. I want to curl up in the fetal position when I imagine him sitting behind the Resolute desk in the Oval Office. But his primal scream of a campaign has done a tremendous service by forcing the GOP establishment to deal with truths it would prefer to ignore. Trump runs around letting cats out of bags, and they are not easily put back in.

Republicans love to talk tough about illegal immigration, for example, and use the issue to bludgeon Democrats. But when Trump takes the bombast to its logical conclusion — all right, then, let’s deport the 11 million undocumented — the establishment has to hem and haw about how all that partisan rhetoric wasn’t meant to be taken literally.

Likewise, Republicans love to suggest that Democrats are somehow soft in the fight against terrorism here and abroad. A favorite trope is to complain that Obama refuses to “utter the words ‘radical Islamic terrorism,’ ” as Ted Cruz is fond of saying. But when Trump called for temporarily banning all foreign Muslims from entering the country, other candidates who try their best to sound hawkish had to acknowledge that Islam itself isn’t really the problem.

Trump challenges his party’s economic orthodoxy as well. He calls himself a “free trader” but opposes existing trade pacts as unfair; Republicans have historically championed free trade but are loath to examine what agreements such as NAFTA have really meant for working-class jobs. Trump promises to somehow reduce the $19 trillion national debt but wants to expand entitlements, not shrink them; many GOP voters, it turns out, feel the same way.

But the biggest transgression, perhaps, was to cite a more accurate history of the Bush administration’s “war on terror.” Months ago, Trump pressured all the other candidates — including Jeb Bush — into agreeing that the war in Iraq was a mistake. Now he is challenging what I call the Bogeyman Claim: Vote for Democrats, and terrorists will come and get you. Vote for Republicans, and your family will be safe.

Saturday night’s debate was nothing short of a bare-knuckles brawl, full of personal attacks and allegations of bald-faced lying. But the most serious damage was not to any candidate but to the GOP’s carefully constructed fantasy world. It’s unclear whether one of the first Republicans, Abraham Lincoln, actually said this, but it’s true: You can’t fool all of the people all of the time.

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