COURTESY CBS

When Vice-President Joe Biden arrived to tape “The Late Show with Stephen Colbert,” on Thursday, it had the makings of an ordinary, slightly decorous affair. Two nights earlier, the guest, Jeb Bush, had put in a serviceable performance: hands clasped, a look on his face that was only slightly terrified. Bush didn’t know how Colbert would play it, so Bush maintained the wary, affable bearing of a dad plucked from the audience to go onstage at a magic show.

But with Biden Colbert wasn’t going for laughs. Biden, of course, has been grieving for his son, Beau, who died on May 30th of brain cancer, while discussing, with more openness than most politicians, the emotional costs of a potential run for President. Colbert asked Biden how he kept a “soul” in Washington, and Biden replied with an old line about Amtrak—“I commuted every day for thirty-six years”—before turning serious. He admitted that the culture of falsity in D.C. baffled him. He wondered “why in the world would you want the job if you couldn’t say what you believe.” Colbert offered condolences, and asked him for a story about Beau. “I never once—my word as a Biden—never ever heard my child complain.” He recalled a conversation shortly before Beau died, when Beau said, “Dad, I know how much you love me. Promise me you’re going to be all right.”

Biden was looking down, eyes wet, staring at his hands, kneading them. He went on, “I don’t know what it was about him. He had this enormous sense of empathy. I’m not making this up. I know I sound like a father.”

In 1972, Biden’s first wife, and their daughter, were killed in a car accident. Colbert, a fellow Catholic, asked Biden how his faith had helped him, and Biden might’ve been tempted to draw a gentle distinction between himself and politicians who wield their faith like a weapon. (Earlier that day, Bobby Jindal, a low-polling governor of Louisiana, had said, “It’s clear Donald Trump has never read the Bible.”) Of his own faith, Biden said, “I go to Mass, and I’m able to be just alone. Even in a crowd, you’re alone.” These days, he said, his wife, Jill, sometimes sticks notes on his bathroom mirror to read while he shaves; not long ago, she put up a quote from Kierkegaard: “Faith sees best in the dark.” He said, “The faith doesn’t always stay with you.”

Biden looked down again, elsewhere for a moment. He patted one hand with the other, and looked up at Colbert, eyebrows raised, as if seeing him for the first time. Colbert was asking a question about “what lessons would you give other people,” and Biden mentioned, as always, an expression from his mother: “As long as you are alive you have an obligation to strive, and you’re not dead until you see the face of God.”

He marvelled at people who have suffered and “don’t have anything like the support I had.” Then he leaned into Colbert, and said, “I’m not going to embarrass you, but you’re one of them, old buddy.” For a moment, Colbert looked genuinely stumped; he smiled, closed his eyes. When Colbert was ten, his father and two brothers were killed in a plane crash. Biden went on, “Losing your dad when you’re a kid . . . It’s like asking what made your mother do it every day? How did she get up every single day?”

Colbert interjected, “She had to take care of me.”

Not immune to an opportunity, Biden grinned and said, “I imagine that would be a hell of a job.”

Colbert continued, “After Dad and the boys died, she was emotionally completely shattered.”

The show went to a commercial, and when they came back, the audience was chanting, “Joe! Joe! Joe!”

He loved it. “Be careful what you wish for,” he said.

Eventually, Colbert got around to asking about the campaign, recalling that Biden had said recently that he wasn’t sure if he is “emotionally prepared” to run for President. Biden looked up at the klieg lights and gave a jut of the chin. “Look, I don't think any man or woman should run for President unless, No. 1, they know exactly why they would want to be President. And, No. 2, they can look at folks out there and say, ‘I promise you have my whole heart, my whole soul, my energy, and my passion to do this.’ And, and, I’d be lying if I said that I knew I was there. I’m being completely honest. But nobody has a right in my view to seek that office unless they are willing to give it a hundred and ten per cent of who they are.”

Biden circled back to Beau. The Vice-President said that he was recently meeting troops and their families, in Denver. “It was going great,” Biden said. “And then a guy in the back yells, ‘Major Beau Biden! Bronze star, sir! Served with him in Iraq.’ And all of a sudden, I lost it.” Biden smiled—a grateful but haunted smile. “How can you—That’s not—I shouldn’t be saying this.” He trailed off.

The eighteen minutes that Joe Biden spoke with Stephen Colbert produced the most public and painful demonstration of emotional honesty by any politician in months, if not years. Biden could never speak in a campaign quite the way that he spoke on Colbert. But a version of that would be powerful, and it was impossible not to see, in the Biden interview, a rebuttal to Trump’s moment in America—to the notion of self-promotion as success, of cruelty as candor, of empathy as weakness. Biden is no naïf; after a half-century in politics, he knew that he was doing well on that stage, and one suspects that he also knows the delicate risks inherent in seeking to convert deep good will into political capital.

The familiar reasons why Biden would be a long-shot candidate remain what they were a week ago. Most importantly, a candidate is never more popular than on the day before he announces. But, already, the 2016 campaign has upturned expectations about what the political class thought Americans want most. Hillary Clinton is confronting more than a strategic deficit. (A Times headline this week: “Hillary Clinton to Show More Humor and Heart, Aides Say.”) If Bernie Sanders and Donald Trump can excite voters by simply suggesting the presence of candor, real or imagined, what would be the reaction to a candidate who doesn’t need to strain to say what he believes?