Donald Trump. AP In poker, there is a concept called "tilt."

When a poker player is on tilt, that means he's angry, and his anger is interfering with his judgment. A player on tilt will tend to play aggressively, but not in a good way — he'll make big bets when he has a bad hand, and then he'll lose.

You might remember the climactic scene in "Rounders," in which Mike McDermott discovers his poker nemesis Teddy KGB has a serious "tell." You can figure out whether Teddy has a good hand based on the way he eats his Oreos.

One way to use this information would be to keep quiet, sit back, watch him eat, and bet accordingly. But Mike realizes that if he reveals to Teddy that he knows about the tell, Teddy will flip out and go on tilt, making bad choices and ultimately losing all his chips.

This is roughly what Hillary Clinton did to Donald Trump on Monday. It worked better than Clinton could possibly have imagined.

Ahead of Monday night's debate, one of the facts we knew about Clinton's preparation was that she was consulting with a team of psychologists about how to get under Trump's skin.

"Her campaign is preparing ways for her to unnerve Mr. Trump and provoke him to rant and rave," The New York Times reported.

This worked during the debate. But more impressively, it has worked for days after the debate.

Clinton has gotten Trump to spend the whole week litigating the question of whether he was out of line to publicly humiliate then-Miss Universe Alicia Machado over her weight gain in 1996.

Clinton based her debate strategy on a key insight: Trump has poor impulse control, but he is more impulsive at some times than others. He is not always an uncontrollable pile of sputtering rage — he was more controlled than normal during the month leading up to the debate — but if you find the right way to provoke him, you can send him off the rails.

Over the past few months, he has seemed less able to stifle himself when he is under attack (as during the Democratic convention) when he believes his campaign aides are second-guessing his choices (as when Paul Manafort was too openly discussing the need for Trump to change) or when he is slipping in the polls (the way he was immediately after the Democratic convention).

Trump with Hillary Clinton at Monday night's debate. Spencer Platt/Getty Images

Having observed this, Clinton set off a series of dominoes.

She attacked Trump where he is sensitive — calling him "Donald," questioning his wealth, bringing up past feuds — and got him not only to lash out in self-destructive ways but also to be so distracted by the need to lash out that he forgot to bring up key attacks on Clinton.

After Trump flunked the debate, his advisers predictably leaked all over about how they tried and failed to get him to prepare. This further angered Trump, leading his campaign to organize a conference call with surrogates and supporters instructing them to stop leaking and start saying Trump had won the debate.

The substance of that conference call predictably leaked too, leading the man who practically invented the phrase "many people are saying" to tweet at 3:20 a.m. that any story about his campaign based on anonymous sources was based on lies.

The bad debate has also hurt Trump's poll standing, and as Trump comes to realize the polls are deteriorating he will most likely become angrier and more erratic — at a time when he ought to be trying to become calmer and more prepared for the next debate on October 9.

Alicia Machado turns out to have had a more checkered past than most people realized on debate night, a fact that makes some people wonder whether the Clinton campaign fully vetted her before putting her in the national spotlight.

My guess is the Clinton campaign knew exactly what it was doing.

Trump at a rally with supporters in Council Bluffs, Iowa. Thomson Reuters

The existence of scandal around Machado made it irresistible for Trump to spend his week insisting that Machado was the real villain here — a message choice that made Trump look petty and silly even before he urged voters in a series of overnight tweets to check out Machado's "sex tape" (which is actually a clip from "La Granja VIP," a reality show about C-list celebrities working on a farm).

A rational candidate, coolly focused on what message he could send to best win over voters, would understand that there is nothing to gain by arguing about whether Machado is a good person, let alone about whether her weight gain was "a real problem."

But Trump is not rational. He's on tilt.

In poker, if you go on tilt, the best strategy is to stop playing. Get up, step away from the table, and come back to play again only when your mood has normalized.

You don't have that option in a presidential campaign, but I'd note even more importantly that you don't have the option in the presidency. If Clinton can get inside Trump's head so easily, foreign leaders will be able to do so, too. This personality trait would make Trump a very dangerous president.

Fortunately, it has also made him a danger to himself in his own campaign.

Trump has no option to take a tilt break. My expectation is he will come back to debate on October 9 still mad as hell — and I also expect that Clinton has plans up her sleeve to make him even more unhinged.