The GOP presidential nominee is out on the trail ahead of the general election in November.

The GOP presidential nominee is out on the trail ahead of the general election in November.

Donald J. Trump has now driven home, in a way no apologist, enabler or timid analyst can plausibly deny, that he is far too nasty, immature and frighteningly undisciplined to be president.

And thanks to Hillary Clinton for the assist: By using the first debate to bring up the case of a Miss Universe who, Trump decided, had put on too much weight, the Democratic nominee unleashed the ugly inner Donald — the man whom the candidate and his handlers have been trying to hide.

This should be a wake-up call to political analysts who have gone out of their way since Trump announced his candidacy to pretend that he was the ingenious creator of a political special sauce who deserved our respect for “speaking his mind.” No, Trump all along has been a clinically self-involved con man who never took the issues, the presidency or the future of our country seriously. Can there be any doubt that his campaign is a branding exercise gone, quite literally, mad?

Trump’s gift to voters was a series of tweets he started sending out at 3:20 a.m. Friday morning. His behavior gives new meaning to the old ads about 3 a.m. phone calls questioning how a would-be president might respond to crisis. Beware any human being who feels an impulse to send out angry tweets at that hour.

[Trump’s ludicrous spin on his taxes doesn’t pass the laugh test]

At a rally in Coral Springs, Fla., Sept. 30, Democratic presidential nominee Hillary Clinton attacked her opponent Donald Trump for tweets he sent out in the early hours of the night before. (The Washington Post)

The first, interestingly, was an expression of pure paranoia about his own campaign. “Anytime you see a story about me or my campaign saying ‘sources said,’ DO NOT believe it. There are no sources, they are just made up lies!”

This, presumably, was a response to stories such as a New York Times account by Patrick Healy, Ashley Parker and Maggie Haberman based on conversations with Trump lieutenants. The Times had reported that Trump “found it hard to focus” during his shambolic debate preparations and that he “did not seem to pay attention during the practice sessions.” Not exactly the traits you want in a chief executive with power over our military, the FBI and the nuclear button.

A couple of hours later, between 5:14 and 5:30, he turned to tweets about Alicia Machado, the Miss Universe winner who, as Clinton pointed out, faced criticisms from Trump over her physique after she won her crown in 1996.

The most remarkable was: “Did Crooked Hillary help disgusting (check out sex tape and past) Alicia M become a U.S. citizen so she could use her in the debate?”

Parsing that one would require a phalanx of psychologists. Can you imagine any other candidate for our highest office even talking about a “sex tape”? And on the facts, Trump has little backup, apparently only what The Post called “racy but not explicit footage from a Spanish-language reality television show.”

And notice the paranoia-laced innuendo. What does he think he can gain by saying that Clinton gave “help” to Machado in gaining citizenship? Is he trying to prompt stories about a new underhanded Clinton trick to help one of his tormentors gain the right to cast a ballot?

[The clear and present danger of Donald Trump]

If this Trump episode does not lead to a flood of defections among Republican politicians supporting him, they will be on record as putting party loyalty (or fear of Trump’s followers in GOP primaries) over the need to protect the nation from a truly unhinged leader. And this should be the end of the pretense, which sometimes drives the media, that whatever might be wrong with Trump, there are things equally wrong with Clinton. Sorry. Clinton may have her problems, but she has never, ever behaved like this.

That a political party, a political system and a media blessed with broad constitutional freedoms have allowed a man like this to get so close to the presidency should be a matter for serious introspection.

And that introspection should start now. Every time Trump has shown us how outlandishly ill-suited he is for the presidency, his outrages have been allowed to fade. Again and again he has been given opportunities to normalize his candidacy. Many can’t believe that a major party nominated someone like him. Their solution is to pretend he’s someone else.

If an onslaught against a Gold Star family didn’t stop him, why should his wee-hours-of-the-morning storm of vicious invective be any different?

The answer is that this episode should finally force everyone to say: enough. Trump is neither normal nor stable. He is manifestly dangerous to our country and erratic in everything except his unrestrained meanness. He should not be given fifth, sixth and seventh chances. He has shown us who he is. We should believe what we see.

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