In politics and business, we lionize leadership. But how much do we really know about what makes a great leader? Illustration by Nishant Choksi

The Titanic sank on April 15, 1912. Nine days later, Thomas Hardy composed a poem about the disaster called “The Convergence of the Twain.” Many poets were mourning the dead; Hardy took a different approach. He asked readers to contemplate the accident’s prehistory: to imagine how, even as the great ship was being built, the iceberg—its “sinister mate”—had also been growing. “No mortal eye could see / The intimate welding of their later history,” Hardy wrote. But, even so, “They were bent / By paths coincident / On being anon twin halves of one august event.”

The poem’s theory of history—as something that unfolds through fated convergences—is also a theory of leadership. For leadership to exist, a leader must cross paths with a crisis; an exemplary person must meet her “sinister mate.” Without an answering crisis, a would-be leader remains just a promising custodian of potential. (Imagine Lincoln without the Civil War or F.D.R. without the Depression.) Before a leader can pull us out of despair, we have to fall into it. For this reason, a melancholy ambivalence can cling to even the most inspiring stories of leadership.

People who fetishize leadership sometimes find themselves longing for crisis. They yearn for emergency, dreaming of a doomsday to be narrowly averted. Last month, Donald Trump’s campaign released its first official TV advertisement. The ad features a procession of alarming images—the San Bernardino shooters, a crowd at passport control, the flag of Syria’s Al Nusra Front—designed to communicate the idea of a country under siege. But the ad does more than stoke fear; it also excites, because it suggests that we’ve arrived at a moment welcoming to the emergence of a strong and electrifying leader. (Trump, a voice-over explains, will “quickly cut the head off ISIS—and take their oil.”) By making America’s moment of crisis seem as big (or “huge”) as possible, Trump makes himself seem more consequential, too.

Many of today’s challenges are too complex to yield to the exercise of leadership alone. Even so, we are inclined to see the problems of the present in terms of crises and leaders. “Crises of leadership are the order of the day at the beginning of the twenty-first century,” Elizabeth Samet writes, in the introduction to “Leadership: Essential Writings by Our Greatest Thinkers” (Norton). “If we live in a world of crisis,” she continues, “we also live in a world that romanticizes crisis—that finds in it fodder for an addiction to the twenty-four-hour news cycle, multiple information streams, and constant stimulation.” Samet believes that our growing addiction to the narrative of crisis has gone hand in hand with an increasing veneration of leadership—a veneration that leaves us vulnerable to “the false prophets, the smooth operators, the gangsters, and the demagogues” who say they can save us. She quotes John Adams, who suggested, in a letter to a friend, that there was something both undemocratic and unwise in the lionization of leadership. The country won’t improve, Adams wrote, until the people begin to “consider themselves as the fountain of power.” He went on, “They must be taught to reverence themselves, instead of adoring their servants, their generals, admirals, bishops, and statesmen.” It can be dangerous to decide that you need to be led.

Our faith in the value of leadership is durable—it survives, again and again, our disappointment with actual leaders. Polls suggest that, even though voters who support Trump are frustrated with the people in charge, they aren’t disillusioned about leadership in general: they are attracted to Trump’s “leadership qualities” and to an authoritarian view of life. In a sense, they’re caught in a feedback loop. The glorification of leadership makes existing leaders seem disappointing by comparison, leading to an ever more desperate search for “real” leaders to replace them. Trump’s supporters aren’t the only ones caught in this loop. Schools that used to talk about “citizenship” now claim to train “the leaders of tomorrow”; academics study leadership in think tanks and institutes; leadership experts emote their way through talks about it on YouTube. According to an analysis by the consulting firm McKinsey, two-thirds of executives say that “leadership development and succession management” constitute their No. 1 “human capital priority”; another study found that American companies spend almost fourteen billion dollars annually on leadership-training seminars.

Presidential candidates, of course, invoke the idea of leadership with special urgency. In his victory speech after the Iowa caucuses, Ted Cruz praised Rick Perry, Glenn Beck, and other “leaders who have stood and led”; in the sixteen Presidential debates since August, candidates have used the word “leadership” more than a hundred times. It’s an especially useful term for politicians. “Experience” and “expertise” are virtues with downsides. “Leadership” sums up, in a vague way, everything that’s desirable and none of what’s not.

If you’re flexible in how you translate the word “leadership,” you’ll find that people have been thinking about it for a very long time. Plato, Confucius, and the poet (or poets) who wrote the Bhagavad Gita thought about leadership; so did Machiavelli. Historians have detailed the lives and decisions of individual leaders. Still, case studies and books of leadership advice don’t add up to the kind of systematic description you’d need in order to say that someone has “leadership qualities.” The attempt to create that description—to develop, essentially, a science of leadership—began around a century ago, but has met little success.

In 1991, Joseph Rost, a professor of leadership studies at the University of San Diego, read as much of the modern leadership literature as he could, reaching back to 1900. (After reading a comparatively small stack of leadership books, I am in awe of his achievement.) Rost found that writers on leadership had defined it in more than two hundred ways. Often, they glided between incompatible definitions within the same book: they argued that leaders should be simultaneously decisive and flexible, or visionary and open-minded. The closest they came to a consensus definition of leadership was the idea that it was “good management.” In practice, Rost wrote, “leadership is a word that has come to mean all things to all people.” He urged his colleagues to get their act together and, a few years later, retired.

In the two decades since, dozens of academic programs have sprung up to study leadership. It’s now possible to get a Ph.D. in “leadership and change” or “ethical and creative leadership.” This hasn’t clarified anything. In a book called “The End of Leadership,” from 2012, Barbara Kellerman, a founding director of the Harvard Kennedy School’s Center for Public Leadership, wrote that “we don’t have much better an idea of how to grow good leaders, or of how to stop or at least slow bad leaders, than we did a hundred or even a thousand years ago.” She points out that, historically, the “trajectory” of leadership has been “about the devolution of power,” from the king to the voters, say, or the boss to the shareholders. In recent years, technological and economic changes like social media and globalization have made leaders less powerful.

Leadership may be, by its nature, an anxious and inconstant idea. Like “status” or “alienation,” the word “leadership” points not toward a stable concept but toward a problem or affliction unique to modernity. In the 1922 book “Economy and Society,” a foundational text in the study of leadership, the sociologist Max Weber distinguished between the “charismatic” leadership of traditional societies and the “bureaucratic” leadership on offer in the industrialized world. In the past, Weber wrote, the world revolved around “old-type” rulers, who could be “moved by personal sympathy and favor, by grace and gratitude.” Modern rulers, by contrast, are supposed to be emotionally detached; they work within a network of laws and systems designed to eliminate nonrational considerations like love and hatred. Weber was getting at a core problem for modern leaders. How can the performance of bureaucratic tasks (such as the design of a health-care overhaul) be infused with charismatic warmth? Conversely, how can you realize your personal ambitions (say, toppling a Middle Eastern autocrat who tried to kill your father) within the systems of bureaucracy? How, in short, can the charismatic and the bureaucratic be combined? Perhaps leadership is confusing because it’s confused: it embodies one of the central conundrums of modern life.