The new media ecosystem “means everything is true and nothing is true,” Obama told me later. “An explanation of climate change from a Nobel Prize-winning physicist looks exactly the same on your Facebook page as the denial of climate change by somebody on the Koch brothers’ payroll. And the capacity to disseminate misinformation, wild conspiracy theories, to paint the opposition in wildly negative light without any rebuttal—that has accelerated in ways that much more sharply polarize the electorate and make it very difficult to have a common conversation.”

That marked a decisive change from previous political eras, he maintained. “Ideally, in a democracy, everybody would agree that climate change is the consequence of man-made behavior, because that’s what ninety-nine per cent of scientists tell us,” he said. “And then we would have a debate about how to fix it. That’s how, in the seventies, eighties, and nineties, you had Republicans supporting the Clean Air Act and you had a market-based fix for acid rain rather than a command-and-control approach. So you’d argue about means, but there was a baseline of facts that we could all work off of. And now we just don’t have that.”

That night in Charlotte, Obama was even more energetic at the microphone. There was not one visible Trump supporter to divert him or the crowd. He unspooled the usual litany of Trump’s violations of fact and human dignity. The race was personal to him, it seemed, and not merely because Trump threatened his legacy.

“Every day, this is a candidate who has said things that just four years ago, just eight years ago, twelve, we would have considered completely disqualifying,” he told the audience. “I mean, imagine if in 2008 I had said any of the things that this man said. Imagine if I had behaved in the way this man behaved. Imagine what Republicans would have said! Imagine what the press would have said!”

On the way out of the pavilion, Obama signed a few books, posed for some pictures, and seemed distinctly pleased with the way things were going. “I’m like Mick Jagger,” he said. “I’m old, I’m gray, but people still turn out.”

In the car, riding back to the Charlotte airport, Obama slumped in his seat and read a few e-mails on his phone. Then he brought up a video of the White House Halloween party.

“Check this out,” he said, holding the phone up to me. On the screen was a toddler with slicked-back hair and a Superman costume. The child’s superpowers extended to an unusual political knowledge: he called Obama “POTUS,” which seemed curiously precocious, until I learned that he was the two-year-old son of Josh Earnest, Obama’s press secretary.

As we rode toward the airport, Obama talked about Trump. “We’ve seen this coming,” he said. “Donald Trump is not an outlier; he is a culmination, a logical conclusion of the rhetoric and tactics of the Republican Party for the past ten, fifteen, twenty years. What surprised me was the degree to which those tactics and rhetoric completely jumped the rails. There were no governing principles, there was no one to say, ‘No, this is going too far, this isn’t what we stand for.’ But we’ve seen it for eight years, even with reasonable people like John Boehner, who, when push came to shove, wouldn’t push back against these currents.”

I asked about Trump’s capacity to eliminate serially a long string of Republican contenders. “Donald Trump beating fifteen people said less about his skills and more about the lack of skills of the people he beat,” Obama said. “But, obviously, he tapped into something. He’s able to distill the anger and resentment and the sense of aggrievement. And he is skillful at challenging the conventions in a way that makes people feel something and that gives them some satisfaction.”

Obama noted that many of Trump’s supporters had voted for him—in Iowa, in Michigan and Wisconsin, in Florida and North Carolina. Part of the reason, he said, was that he had the good fortune to appear on the scene before the collapse of the old media order. In the late nineties, when he was a state senator representing Hyde Park, on the South Side of Chicago, he started making trips to the southern counties of Illinois with a white political operative named Dan Shomon. As a legislator, Obama had never before been south of Springfield. Michelle Obama was at home, pregnant, and Obama figured that this was his last chance before the baby arrived. As he headed south, he came to realize that he was now in a place that was closer in character and outlook to Tennessee and Arkansas than to Chicago. He met with people on factory floors and at the local Maid-Rite. In Du Quoin, he learned about the problems posed by an all-white branch of the Chicago gang called the Gangster Disciples; in Old Shawneetown, he learned about farm life from people like Steve and Kappy Scates, who are friends to this day. “What those trips proved is that he appealed to rural white people,” Shomon once told me. “They would vote for him, they liked him.” In 2004, Obama won a seat in the U.S. Senate, defeating in the primary a sitting state comptroller and white Party regular named Dan Hynes, who had had the support of nearly every county chairman in the state.

“People didn’t see me coming,” Obama said as we drove through the night. “In southern Illinois, in those counties I won, I was at V.F.W.s and fish fries hearing people’s stories and talking to folks, so that they knew me. They weren’t getting me through Fox or Rush Limbaugh or Breitbart or RedState.

“In ’08, they saw me coming, but I was a guy named Barack Hussein Obama coming up against the Clinton machine, so no way! So they weren’t focussed on me, and I established a connection. Then came the stuff: Ayers and Reverend Wright and all the rest. What I’m suggesting is that the lens through which people understand politics and politicians is extraordinarily powerful. And Trump understands the new ecosystem, in which facts and truth don’t matter. You attract attention, rouse emotions, and then move on. You can surf those emotions. I’ve said it before, but if I watched Fox I wouldn’t vote for me!”

Obama will go down in history as the first African-American President, and he derives immense pride from that, but he never fails to insist on the complexity of his story. “I’m half Scotch-Irish, man!” he said. “When folks like Jim Webb write about Scotch-Irish stock in West Virginia and Kansas and so on, those are my people! They don’t know it, always, but they are.”

Now, on the eve of the election, nothing was in the bag. “What’s powerful is that ideas can change on a dime,” Obama said as we pulled up to Air Force One. “Public attitudes can be shaped and shift so radically. Two years ago, Hillary Clinton’s popularity was at sixty-five per cent, and people were contrasting her popularity with mine. There was all this talk about how she was going to need to find ways to distance herself from me. Now, suddenly, she has problems with public opinion. Part of it is, I’m less the focus. But it all happens so fast. This is a puzzle I’m going to be thinking about a lot. I have complete confidence in the American people—that if I can have a conversation with them they’ll choose what’s right. At an emotional level, they want to do the right thing if they have the information.” And yet in an age of filter bubbles and social-media silos, he knew, the “information” that reached people was increasingly shaped by what they wanted to be true. And that was no longer in his hands or anyone else’s.

Obama’s final appearance, on the eve of Election Day, was at an outdoor rally next to Independence Hall, in Philadelphia, alongside Jon Bon Jovi, Bruce Springsteen, and the Clintons. But it was preceded by visits to Florida, Michigan, and New Hampshire, where he travelled with Maggie Hassan, that state’s Democratic candidate for the Senate. As Obama later recounted to me, he found himself reminiscing with her about the tense magic of a campaign’s conclusion: “I love the stillness and the mystery of the day or two before elections, because in a lot of ways everything goes radio-silent. Nobody at that point is really listening to an argument. The infrastructure is set. And now it’s this weird alchemy that’s taking place in the country, and you just have to kind of wait and see how it works. But there’s always this mystery to it, this possibility.”