One of the most patriotic toasts, often used at social occasions in the military, is “To the President of the United States.” It is part of what binds us as a country and it is a hallmark of the social compact that supports the world’s most successful democracy.

Donald Trump — during the last presidential debate of his fast-imploding career — repudiated that proud tradition with the most shocking comment that he has uttered in his inflammatory campaign. Asked whether he would accept the results of an election that he seems destined to lose, Trump said, “What I’m saying is that I will tell you at the time. I’ll keep you in suspense.”

During the same answer, Trump rediscovered his authoritarian side by dramatically announcing that his Democratic opponent “shouldn’t be allowed to run. It’s crooked.” That’s right — because of charges about her homebrew email server that the FBI director said did not warrant prosecution — Trump would have banned Hillary Clinton from the ballot.

It is worth recalling that in 1920, Eugene Debs, as the Socialist candidate for president, received nearly 1 million votes while serving as Prisoner 9653 in the Atlanta Federal Penitentiary. Debs’ conviction for opposing American entry into World War I was unjust. But back in 1920, no one suggested that he should be banned from the ballot in a democracy.

Little more than three weeks ago, on a debate stage at Hofstra University, the last realistic hope of a Trump presidency died. The polls today might have been different if the former reality show host had actually rehearsed for the first debate; had he refrained from bragging about not paying taxes; had he resisted the urge to interrupt the first woman nominated for president; and had he not taken Hillary’s bait about his belittling of a Miss Universe winner.

But that would have required a candidate with more maturity than the 70-year-old megalomaniac with a rapidly tarnishing brand.

Somewhere in Trump Tower, there must be a portrait of the pensive, statesmanlike Donald Trump with his chin resting on his right hand as he ponders global problems. But in the reverse of “The Picture of Dorian Gray,” all the grace lies in the portrait while Trump the Candidate is a snarling mass of prejudice, misinformation and deliberate lies.

There was an interlude at the beginning of this debate, adroitly moderated by Chris Wallace, when that other Donald Trump was on display. His answers during the opening segment on the Supreme Court were conventional right-wing Republican boilerplate as he talked about “putting pro-life justices on the court” so that the states would decide whether abortion were legal.

The bilious billionaire even maintained his composure, for a while, when the topic turned to the hot-button issue of immigration. Even as Clinton egged Trump on — suggesting that “he choked” during his meeting with Mexican President Enrique Pena Nieto — the Republican nominee resisted the provocation. That is, until Clinton used a mention of WikiLeaks to switch the subject to Vladimir Putin.

Trump initially held his own by making the apt point, “That was a great pivot off the fact that she wants open borders, OK? How did we get to Putin?” But then, rather than scrambling back to the border issue, Trump insisted on talking about a fantasy world where “Russia and the United States got along well and went after ISIS.”

That gave Clinton an opportunity to use a line that she had obviously rehearsed about how Putin would “rather have a puppet as president of the United States.” Within seconds — in a moment that the late Jim Henson, the creator of the Muppets might have cherished — Trump was reduced to shouting “No puppet. No puppet.”

Before long, as he harked back to a bizarre riff that he has employed whenever Putin was blamed for intruding on the American election, Trump once again denied the assessment of the U.S. intelligence community that Russian hackers were responsible for the WikiLeaks release of Clinton campaign documents. As Trump put it, in a dismissive rejection of his own government’s intelligence briefing, “Our country has no idea.”

But the moment when Trump finally lost his last ounce of self-control — the moment that he forgot every debate briefing that he had dutifully endured — came during the closing minutes of the Vegas Non-Valentine. Of all the trigger lines that Clinton had rehearsed, the one that finally turned Trump into a sputtering firecracker were the words “replenish the Social Security Trust Fund.”

As soon as she uttered that explosive phrase, Trump interrupted with an epithet that will be a centerpiece of all college gender studies courses for the next generation, “Such a nasty woman.”

One of Trump’s favorite words is “disaster” which he used 10 times in the debate to describe everything from trade deals to open borders to Aleppo to Obamacare to life in the inner city. But what is an unmentioned disaster is the presidential campaign of the man that a cheering Republican Party nominated in Cleveland.

Trump, judging from the polls and his performance in the final debate, is headed for a presidential defeat on par with Michael Dukakis’ loss to a triumphant George H.W. Bush in 1988. That was a year when the Democrats should have won back the White House after a sad-eyed, scandal-plagued end to the Ronald Reagan presidency. But they nominated the wrong candidate.

Michael Dukakis is an honorable man. Trump is an affront to American democracy and the political party that nominated him. I hope that Republican Chairman Reince Priebus — who pronounced the GOP race over after the May 3 Indiana primary and stifled dissent at the Cleveland convention — enjoyed the last debate of a drowning Trump candidacy.