Several years ago, Tom Nichols started writing a book about ignorance and unreason in American public discourse—and then he watched it come to life all around him, in ways starker than he had imagined. A political scientist who has taught for more than a decade in the Harvard Extension School, he had begun noticing what he perceived as a new and accelerating—and dangerous—hostility toward established knowledge. People were no longer merely uninformed, Nichols says, but “aggressively wrong” and unwilling to learn. They actively resisted facts that might alter their preexisting beliefs. They insisted that all opinions, however uninformed, be treated as equally serious. And they rejected professional know-how, he says, with such anger. That shook him.

Skepticism toward intellectual authority is bone-deep in the American character, as much a part of the nation’s origin story as the founders’ Enlightenment principles. Overall, that skepticism is a healthy impulse, Nichols believes. But what he was observing was something else, something malignant and deliberate, a collapse of functional citizenship. “Americans have reached a point where ignorance, especially of anything related to public policy, is an actual virtue,” he would write in the preface to The Death of Expertise: The Campaign Against Expertise and Why It Matters, which was published by Oxford last year and quickly became a bestseller. “To reject the advice of experts is to assert autonomy, a way for Americans to insulate their increasingly fragile egos from ever being told they’re wrong about anything.” Further down the page, he would add: “I’m worried.”

Nichols is best known these days as an outspoken “Never Trump” Republican, a lifelong conservative whose snappy Twitter feed is the site of quips and skirmishes and occasional drawn blood, and whose op-eds in publications like The Washington Post, The New York Times, and USA Today sharply dispraise the U.S. president and his supporters. An “increasingly hideous movement,” Nichols labeled candidate Trump’s rising popularity in early 2016; and this past November, noting the “moral depths” the administration was plumbing, he argued for shaming (rather than more softly engaging) voters who still stood behind a “cast of characters in Washington who make the ‘swamps’ of previous administrations look like experiments in good government.”

The Death of Expertise resonated deeply with readers. Soaring sales kept Nichols on the road for much of last year, speaking before packed audiences in Texas and New York and Missouri and California and Washington D.C., as well as Australia and Canada and the UK and the Czech Republic. He was interviewed on CSPAN, NPR, Comedy Central, MSNBC. The book was translated into nearly a dozen languages. In December, Politico named Nichols to its annual list of 50 people whose ideas are “blowing up American politics,” and Foreign Affairs listed an article excerpted from his book as one of its best, and best-read, of 2017. Readers regularly approach Nichols with stories of their own disregarded expertise: doctors, lawyers, plumbers, electricians who’ve gotten used to being second-guessed by customers and clients and patients who know little or nothing about their work. “So many people over the past year have walked up to me and said, ‘You wrote what I was thinking,’” he says.

His own expertise is in nuclear policy and Russian affairs—during the Cold War, he was what was called a Sovietologist—and Nichols is a professor at the U.S. Naval War College. Since 2005 he has also taught at the extension school, on subjects like international security, nuclear deterrence, and Cold War pop culture (“That’s a fun one”). His previous books have titles like Eve of Destruction: The Coming Age of Preventive War, and No Use: Nuclear Weapons and U.S. National Security. A self-described “’80s guy” in loafers and khakis, he is 57, a mix of warmth and directness and slight exasperation. There’s a brisk, suffer-no-fools self-assurance about him. Somehow he always seems to be in motion, even when he is standing still.

The Death of Expertise began as a cri de coeur on his now-defunct blog in late 2013. This was during the Edward Snowden revelations, which to Nichols’s eye, and that of other intelligence experts, looked unmistakably like a Russian operation. “I was trying to tell people, ‘Look, trust me, I’m a Russia guy; there’s a Russian hand behind this.’ ” But he found more arguments than takers. “Young people wanted to believe Snowden was a hero.” Finally one day, someone said to him, “ ‘Tom, I don’t think you understand Russia. Let me explain Russia to you.’ This was a person who didn’t know where Russia was three months earlier.” The dam broke. He pounded out a blog post that got picked up by The Federalist, and not long after that, an editor from Oxford University Press called.

From the beginning, discussion of The Death of Expertise was inextricably bound up with Donald Trump. The book appeared less than six months after the upheaval of the 2016 election, and barely three months into the new presidency, and it seemed to have been composed with Trump in mind: a man, Nichols wrote, who quoted The National Enquirer as a reliable source of news, traded in conspiracy theories, and remained willfully and persistently uninformed about basic issues of public policy. Nichols recalled how a candidate with less experience in public service than any president in the nation’s history had disdained experts and elites during his campaign and promised to banish them from his administration. He cited a Wisconsin rally in early 2016, where Trump had declared, “The experts are terrible. They say, ‘Donald Trump needs a foreign policy adviser’…But supposing I didn’t have one. Would it be worse than what we’re doing now?” Trump’s eventual victory, Nichols wrote, was “undeniably one of the most recent—and one of the loudest—trumpets sounding the impending death of expertise.”

In fact, though, the book was all but finished by the time the election took place, and explicit mention of the winner comes only in its final pages, which were written after the rest of the book went to press. The Death of Expertise diagnoses a malady decades in the making, for which Trump represents only one case, albeit perhaps its most famous and extreme. “I didn’t know ahead of time that Trump was going to happen,” Nichols says now, “but I knew that someday something like him would.”

The indictments the book levels are numerous: misguided egalitarianism run amok; the “protective, swaddling environment” of higher education, whose institutions increasingly treat students as customers to be kept satisfied; the 24-hour news cycle and the pressure on journalists to entertain rather than inform; the chaotic fusion of news and punditry and citizen participation. Meanwhile, the Internet’s openness offers a “Google-fueled, Wikipedia-based, blog-sodden” mirage of knowledge, Nichols argues, and an inexhaustible supply of “facts” to feed any confirmation bias. “The Internet encourages not only the illusion that we are all equally competent,” he says, “but that we are all peers. And we’re not. There was once a time when saying that would have been considered unremarkable.”

Along the way, The Death of Expertise dissects the Dunning-Kruger Effect, formulated in 1999, which holds that the less competent people are, the greater the belief they tend to have in their own competence. Nichols draws from prior cultural studies like Susan Jacoby’s The Age of American Unreason, Robert Hughes’s Culture of Complaint, and Richard Hofstadter’s landmark 1963 work, Anti-Intellectualism in American Life. He explores contemporary phenomena like the anti-vaccination movement and the Obama birther conspiracy theory. There is a chapter on the failures of experts—“like plane crashes, spectacular but rare,” he argues, and a reason to find better experts, not to abandon expertise—and admonitions that experts are the servants and not the masters of democratic society. The book sticks mostly to events in the United States, but Nichols notes similar trends in other countries: the U.K.’s Brexit debate, South Africa’s AIDS denialism in the late 1990s.

At the bottom of all of it, Nichols finds “a growing wave of narcissism.” Voters increasingly see political figures as extensions of themselves—“He’s just like me!”—imagining shared personalities and values. Narcissism elevates feelings above facts, and it breeds social resentment, a major driver, Nichols believes, of the revolt against expertise. “People cannot accept ever being at a disadvantage in a conversation with anybody else,” he says. “It’s a persistent insecurity that goads people into having to say that they know something even when they don’t. Which didn’t used to be the case—we used to be a much more reasonable culture. You know, everybody doesn’t have to know everything.”

Something else, too, gnaws at Nichols: “It strikes me that the affluence and convenience of modern society lull people into thinking that it all kind of happens magically, without any human intervention. People live in a world that functions, and not just because of technical experts, but policy experts too.” Americans can board an airplane and fly almost anywhere in the world, unencumbered—a triumph of pilots and aeronautical engineers, but also of diplomats and air-traffic control regulators and transportation security policymakers. “People have just gotten used to remarkable ease,” he says. “They look around and say, ‘How hard could this be?’ You know? ‘How hard can it be?’…That idea is totally animating our political life right now. People say, ‘We’ll elect Donald Trump and he’ll just put in a bunch of guys. We don’t need those experts. That’s the swamp. Because, really, how hard can any of this be?’”

Nichols grew up in Chicopee, Massachusetts, a mill town about 90 miles west of Cambridge. His father was a cop who later worked his way up from the loading dock of a local chemical factory to become a gray-collar middle manager; his mother was executive secretary to the owner of a paper plant. She never finished high school. “Entirely self-taught,” Nichols says. The child of a second marriage, he has three half-siblings, though they were mostly grown by the time he came along. “I just had this classic ‘60s working-class childhood.”

Except for one thing: the Cold War was inescapable in Chicopee. The city was home to Strategic Air Command’s East Coast bomber base; the daily roar overhead used to rattle the china in his family’s dining-room cabinet. At nine years old, he knew that if nuclear war broke out, “We weren’t going to survive; we were going to go pretty quick.” During fire drills in first and second grade—that’s what the teachers called them, though they weren’t really fire drills at all—he and his classmates were lined up against the wall and told to cover their faces. Other kids he knew were simply to be sent home, to die with their families. “I’ve talked to people who grew up in military towns in the Soviet Union who had the same experience,” Nichols says. “It was a little mind-blowing—this existential global threat you’re suddenly aware of as a child.”

After high school, Nichols enrolled at Boston University, first as a chemistry major—a solid, employable field, he figured. Within a year he’d switched to Russian and international relations. From there he went on to a master’s degree at Columbia in political science and Soviet studies, and then a Georgetown political-science Ph.D. He received his doctorate in 1988, about 18 months before the Berlin Wall came down. The night the Soviet Union collapsed two years later, Nichols was at a Christmas party in Chicopee. He was a professor at Dartmouth, having recently finished up a year and a half as a legislative aide on Capitol Hill. He’d been in Moscow the previous month, his fourth visit to the country in a decade. During his first trip, in 1983, he spent a summer studying in Leningrad. Local people were terrified to talk to him because he was an American, and he remembers seeing churches watched by the KGB and propaganda posters everywhere. The whole place was a sealed bubble. “I was there for an entire summer and I didn’t know anything that happened in the world outside. No telephones, no computers, no foreign newspapers.” He mailed postcards home to his parents that arrived in the United States after he did. “I literally went out to the mailbox one day and picked up my own postcard.”

By his 1991 journey to Moscow, the Soviet Union seemed markedly different. “It was superpower in freefall,” Nichols recalls. “I was really worried about the potential of the whole thing exploding. I mean, it was chaos. There were people standing in line for bread.” At the Christmas party in Chicopee, he watched the tape of the Soviet flag being lowered for the last time over the Kremlin and thought, “‘Everything’s different now.’ The whole world that I knew until I was 31 years old was gone.”

People always ask him, “How does this end?” That’s the question Nichols hears most often from readers and interviewers and audience members at speaking events. How does it end? This turn away from expertise, this willfully inexpert presidential administration, this age of ignorance and unreason. He doesn’t know. He hopes the answer is not disaster: “This idea that we don’t really need experts, that everyone knows as much as the experts, it’s the kind of illusion that we can indulge ourselves in until something terrible happens. Everybody wants to second-guess their doctor until their fever hits 104. And then suddenly—I mean, you don’t see a lot of people in emergency rooms arguing with the doctor. When you’re sick enough, when you’re clutching your chest or you’re bleeding or in deep danger, then you go to the emergency room and say, ‘Do whatever you do, doctor.’”

One thing gives him a measure of optimism. “If I have a slogan about the past year in politics, it’s something I stole from the old Barry Goldwater bumper sticker: ‘In your heart, you know he’s right.’ Even the people who resist my argument, in their hearts, they know they’re wrong. People who say, ‘I don’t have to listen to my doctor’—deep down you know you should. The people who say that Donald Trump is right and experts are idiots—deep down you know you’re wrong about that. You’re just angry. I think deep down, people know that this phase we’re going through is unhealthy. Even the people who are immersed in it.”

In truth, though, Nichols really is worried. A year after the book’s publication, he finds himself even more pessimistic than he was when he wrote it. In December, at a JFK Library event on reality and truth in public discourse, a moderator asked him a version of “How does this end?” Nichols and the other panelists—Washington Post senior correspondent Dan Balz and Kathleen Hall Jamieson, director of Penn’s Annenberg Public Policy Center—had spent 45 minutes discussing how established sources of knowledge and facts have been systematically undermined. So, wondered the moderator, Boston College historian Heather Cox Richardson, what did Nichols expect to happen now? “In the longer term, I’m worried about the end of the republic,” he answered. Immense cynicism among the voting public—incited in part by the White House—combined with “staggering” ignorance, he said, is incredibly dangerous. In that environment, anything is possible. “When people have almost no political literacy, you cannot sustain the practices that sustain a democratic republic.” The next day, sitting in front of his fireplace in Rhode Island, where he lives with his wife, Lynn, and daughter, Hope, he added, “We’re in a very perilous place right now.”

There’s an odd echo between the perilousness of now and the course Nichols was teaching at the extension school last fall, “Nuclear Weapons and International Security.” Twenty-six years after the fall of the Soviet Union, his students in Harvard Hall were trying to comprehend the uncertainty that gripped Americans during the Cold War, the sense back then of plunging unavoidably forward, the awareness that vastly different outcomes were all possible. (“I’m glad the Cold War ended,” Nichols said one afternoon at his home, “because the natural endpoint was going to be World War III.”)

Students had learned about fissile materials and delivery systems; they’d studied the basics of deterrence and the proliferation dilemma; nuclear terrorism and rogue states; arms control and “getting to zero.” They’d tried to comprehend the thousands of missiles the United States and USSR kept pointed at each other for decades, the number of times the world came close to annihilation. In one starkly vivid lecture, Nichols had shown just how quickly and completely the aftermath of a single nuclear bomb would overwhelm any medical capacity to help survivors. Meanwhile, they’d all watched the brinksmanship unfolding in real time between Trump and North Korea’s Kim Jong Un. Students brought anxious questions into the classroom, and Nichols answered mostly with uncertainty rooted in the unpredictability of an inexperienced president. “We’re either going to launch a preventive war and be in conflict on the Korean peninsula, which I think would be nuts,” he said one evening, after a presidential tweet had launched another round of headlines, “or we’re going to learn to live with a nuclear North Korea and try to apply the lessons of containment and deterrence that you guys have been studying for the past three months.”

On the last day of class, he and the students returned to a question they’d begun the semester with: what are nuclear weapons for? War? Deterrence? History has strangely failed to nail down an answer, Nichols said. In the early days after Hiroshima and Nagasaki, some feared nuclear attacks would become a regular part of warfare. But no nation since then has dropped a nuclear bomb. “It’s a weird situation that the developed powers have all had a weapon in their arsenals for 73 years now and we’ve not used it,” Nichols said. “Three-quarters of a century, a weapon that no one’s used in battle.”

But that’s his point: something held. “In the end, it boiled down to a very human question: is there anything worth doing this over?” Tens of millions of people would die in minutes, even in a “limited exchange.” Nichols reminded his students that American deaths in World War II totaled about 417,000. Worldwide, that war killed 65 million people. With a nuclear attack, “In 20 or 30 minutes, you’re talking about many multiples of the total American casualties in World War II.…A global exchange would probably kill 500 million to 600 million in a few minutes.” The room fell totally silent.

In The Death of Expertise, Nichols writes about the role of experience in expertise. He describes a Sovietologist at Columbia who could divine hidden policy positions from the featureless sameness of the Soviet press. It seemed like sorcery, but it wasn’t; it was years of practice, skill honed to second nature, a certain kind of intimacy. In class, Nichols had told similar stories about the Cold Warriors, who in one administration after another were responsible for nuclear diplomacy; knowledge and experience about the scale and scope of consequences lent real seriousness to their approach, Nichols said. Today, he said, “I think we’ve forgotten the horribleness of the decision we were contemplating.” However clinically they discussed their options, he added, Cold War officials understood that they were talking about the end of civilization.

“So I guess what I’d like you to take away from this course,” Nichols continued, “is not my view of nuclear weapons, or Kissinger’s view or Putin’s view or anybody else’s, but to approach this question with real seriousness. Because that is part of what I think has kept the peace with nuclear weapons for so long. It’s not just a strategic issue; there is embedded in nuclear weapons a kind of different moral calculus.” And that, too, requires expertise.

In their hearts they know.