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“I’m used to bullies.”

That’s a line Joe Biden has used several times during his run against Donald Trump, and he said it again recently in talking about the first presidential debate.

“I hope I don’t take the bait, because he’s going to say awful things about me, my family, et cetera,” Biden said at a virtual fundraiser. “I hope I don’t get baited into getting into a brawl with this guy, because that’s the only place he’s comfortable.” Biden expects to be able to keep his cool because, he said, “I’m used to dealing with bullies.”

The challenge for Biden isn’t simply that he’ll be facing a bully on the debate stage in Cleveland on Tuesday; it’s that he’ll be facing a man who is shameless and without conscience, a shatterer of norms and boundaries, a liar of epic proportions, a conspiracy-monger who inhabits an alternate reality. President Donald Trump operates outside any normal parameters.

If one is not used to dealing with someone like that, it can be utterly disorienting. Just ask the 2016 GOP primary field, or Hillary Clinton.

“We were on a small stage,” Clinton said about her second debate with Trump, “and no matter where I walked, he followed me closely, staring at me, making faces. It was incredibly uncomfortable. He was literally breathing down my neck. My skin crawled.”

She went on to describe what went through her mind: Should she keep her calm and carry on as if he weren’t repeatedly invading her space, or should she turn to him, look him in the eye, and say, “Back up, you creep. Get away from me. I know you love to intimidate women, but you can’t intimidate me, so back up”? Clinton chose the first option, but in retrospect, she wonders whether she should have chosen the second.

What might Vice President Biden do to prepare for his debates with President Trump?

For starters, I hope the former vice president’s campaign team has consulted psychologists who can help prepare Biden to deal with Trump’s disordered personality.

A second thing Biden can do is put Trump’s words within a larger context. For example, the president is a profligate liar; we know that in the course of the debates the president will tell an avalanche of falsehoods. It might therefore be useful for Biden, early in the debate, to warn viewers what will happen—Trump will lie, and lie again, and lie again. The former vice president should put a frame around those claims, so people understand what’s happening in real time.

In February, a friend pointed out to me that years ago Donald Trump lied about the size of Trump Towers, claiming he lived on the 66th to 68th floors. Here’s the thing: Trump Tower has only 58 floors, according to New York City documents. So Trump lied about even this, as he lies about virtually everything else. (In fact, Trump has lied about the height of several of his buildings, including Trump World Tower, which he claimed has 90 floors. In fact, it has 70.)

If Biden were to use this story at the beginning of a debate, perhaps even before Trump’s first lie, the former vice president, when hearing a lie, could simply say, “Donald, we’re at the 66th floor again.” This response would certainly be more effective than repeatedly calling Trump a liar and serving as a fact-checker for the entire debate. Biden has to find a way to quickly name what’s happening and move on.

When it’s his turn to respond to a comment by Trump, the former vice president should confidently name each strategy Trump attempted—“That was a deflection … That was a hoax … That was scapegoating … We’re at the 66th floor again.” By quickly and succinctly answering any question after naming the strategy, Biden will appear controlled, reasonable, and intelligent; Trump will feel dismissed and mocked. This will enrage the president, especially if his attempts to engage in argument are ignored, and Biden refuses to look at him.

Beyond that, as one clinical psychologist I consulted for this piece suggested, Biden should simply name what is true and what most Americans intuit about the president: He is a terribly broken man. Money and privilege spared him from the consequences that might have helped him develop a conscience. He does not show remorse or guilt, because he does not feel it. Decency and honesty yield no reward for Trump; indecency and lying yield no consequences. He doesn’t apologize to others, because he doesn’t feel the pain of others. He does not have the capacity for empathy and authentic relationships; all his relationships are conditional. He knows only pleasure and pity for himself. He perseverates on the wounds to his ego. Telling the truth, when it’s not Trump’s truth, is viewed as a betrayal by the president, because he always places his interests above truth.

Such a damaged individual may deserve some measure of pity as well as some measure of contempt; but in either case, such a person should not be the president of the United States.

Yet the reality is that such a man is the president, and with every passing day, his pathologies grow worse, his instability becomes more apparent, the danger he poses to American democracy more undeniable. Yesterday, he once again signaled that he has no interest in accepting the election results if he loses. In the summer of 2016, I said of Trump, “with him there’s no bottom.” We’re now seeing what “no bottom” looks like.

The investigative reporter Bob Woodward, whose book Rage is just the most recent, scathing indictment of the Trump presidency, said that historians, looking back at this period, are going to ask, “‘What the F happened to America?’”

The answer is that Donald J. Trump happened to America.

Joseph R. Biden is the only person who can keep Trump to a single term and stop this ongoing American carnage. And that, in turn, could depend in large part on how the former vice president does during the first debate.

I’m a conservative who served in the Ronald Reagan, George H. W. Bush, and George W. Bush administrations. I’m also wishing Joe Biden very well on Tuesday evening. It’s less for his sake than for the sake of the country I love.

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