It was probably always going to come to this. Donald Trump has been telling us for years that he would not accept an electoral defeat. He has cheered violence and threatened insurrection. On Tuesday he tweeted that Democrats and Republicans who weren’t cooperating in his coup attempt should look “at the thousands of people pouring into D.C. They won’t stand for a landslide election victory to be stolen.” He urged his supporters to mass on the capital, tweeting, “Be there, will be wild!” They took him seriously and literally.

The day after Georgia elected its first Black senator — the pastor, no less, of Martin Luther King Jr.’s church — and its first Jewish senator, an insurgent marched through the halls of Congress with a Confederate banner. Someone set up a noose outside. Someone brought zip-tie handcuffs. Lest there be any doubt about their intentions, a few of the marauders wore T-shirts that said “MAGA Civil War, Jan. 6, 2021.”

If you saw Wednesday’s scenes in any other country — vandals scaling walls and breaking windows, parading around the legislature with enemy flags and making themselves at home in quickly abandoned governmental offices — it would be obvious enough that some sort of putsch was underway.

Yet we won’t know for some time what the attack on the Capitol means for this country. Either it marked the beginning of the end of Trumpism, or another stage in the unraveling of American liberal democracy.

There is at least some cause for a curdled sort of optimism. More than any other episode of Trump’s political career — more than the “Access Hollywood” tape or Charlottesville — the day’s desecration and mayhem threw the president’s malignancy into high relief. For years, many of us have waited for the “Have you no sense of decency?” moment when Trump’s demagogic powers would deflate like those of Senator Joseph McCarthy before him. The storming of Congress by a human 8chan thread in thrall to Trump’s delusions may have been it.

Since it happened, there have been once-unthinkable repudiations of the president. The National Association of Manufacturers, a major business group, called on Vice President Mike Pence to consider invoking the 25th Amendment. Trump’s former attorney general Bill Barr, who’d been one of Trump’s most craven defenders, accused the president of betraying his office by “orchestrating a mob.”

Several administration officials resigned, including Trump’s former chief of staff, Mick Mulvaney, who’d been serving as special envoy to Northern Ireland. In an interview with CNBC, Mulvaney was astonishingly self-pitying, complaining that people who “spent time away from our families, put our careers on the line to go work for Donald Trump,” will now forever be remembered for serving “the guy who tried to overtake the government.”

Mulvaney’s insistence that the president is “not the same as he was eight months ago” is transparent nonsense. But his weaselly effort to distance himself is still heartening, a sign that some Republicans suddenly realize that association with Trump has stained them. When the rats start jumping, you know the ship is sinking.

So Trump’s authority is ebbing before our eyes. Having helped deliver the Senate to Democrats, he’s no longer much use to Republicans like Mitch McConnell. With two weeks left in the president’s term, social media has invoked its own version of the 25th Amendment. Twitter, after years of having let Trump spread conspiracy theories and incite brutality on its platform, suddenly had enough: It deleted three of his tweets, locked his account and threatened “permanent suspension.” Facebook and Instagram blocked the president for at least the remainder of his term. He may still be able to launch a nuclear strike in the next two weeks, but he can’t post.

Yet the forces Trump has unleashed can’t simply be stuffed back in the bottle. Most of the Republican House caucus still voted to challenge the legitimacy of Joe Biden’s election. And the MAGA movement’s terrorist fringe may be emboldened by Wednesday’s incursion into the heart of American government.

“The extremist violent faction views today as a huge win,” Elizabeth Neumann, a former Trump counterterrorism official who has accused the president of encouraging white nationalists, told me on Wednesday. She pointed out that “The Turner Diaries,” the seminal white nationalist novel, features a mortar attack on the Capitol. “This is like a right-wing extremist fantasy that has been fulfilled,” she said.

Neumann believes that if Trump immediately left office — either via impeachment, the 25th Amendment or resignation — it would temporarily inflame right-wing extremists, but ultimately marginalize them. “Having such a unified, bipartisan approach, that he is dangerous, that he has to be removed,” would, she said, send “such a strong message to the country that I hope that it wakes up a number of people of good will that have just been deceived.”

In a Twitter thread on Thursday, Kathleen Belew, a scholar of the white power movement, wrote about how, in “The Turner Diaries,” the point of the assault on Congress wasn’t causing mass casualties. It was “showing people that even the Capitol can be attacked.”

Trump’s mob has now demonstrated to the world that the institutions of American democracy are softer targets than most of us imagined. What happens to Trump next will tell us all whether this ailing country still has the will to protect them.

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