In 1971, a few weeks after The New York Times wrapped its explosive series on the Pentagon Papers, the conservative magazine National Review ran a scoop of its own: another set of secret papers, this time showing that victory had been possible in Vietnam if only the U.S. government and military had taken a more aggressive approach.

The stunning revelations triggered widespread coverage—on the wire services, Voice of America, and the front page of The Washington Post—and frantic investigations at the Pentagon and State Department. Only after suspicious editors at the Times began raising questions did William F. Buckley Jr., the founder and editor of National Review, cop to the truth: He and his colleagues had fabricated the papers. Rather than apologize, they blamed the outlets who had run with the story for not double-checking the magazine’s reporting. When that excuse didn’t dim the outrage, Buckley told reporters, through a wry smile, “We admit we proceeded in something of an ethical vacuum.”

Buckley was no stranger to ethical vacuums, as journalist and biographer Sam Tanenhaus shows in his stunning new biography of the conservative personality, Buckley: The Life and the Revolution that Changed America. Throughout his life, Buckley was guided by ideology and personal gain far more than truth and virtue. Yet his charm, generosity, and loyalty ensured that he never paid much of a price for his transgressions. A nationally syndicated columnist at the time of the Pentagon Papers hoax, he laughed it off when 14 papers dropped his column. “Well,” he said, “I am down to 348 papers.” Three hundred and forty-eight papers, one national television show, one magazine, and a direct line to the President of the United States. Life was good inside his ethical vacuum.

Tanenhaus, though no doubt personally charmed by Buckley over the two decades that they knew one another, never avoids his subject’s flaws in this clear-eyed biography. Over nearly 900 pages that fly by thanks to his lively writing, Tanenhaus chronicles Buckley’s fraught relationship to power and truth, his rapid rise through America’s elite institutions, and his sprawling career as a right-wing revolutionary who expanded his inherited social and economic power into political and cultural power—and in the process, helped to mold the United States in his image.

“William F. Buckley, Jr., the intellectual leader of the modern conservative movement, rightly saw himself less as founder than heir,” Tanenhaus writes in the opening pages of Buckley. “Everything he learned, and all he became, began at home.” That home, crammed with ten children, was led by his father W. F. Buckley, whose appetite for risky investment led the family through a series of boom-and-bust cycles that always ended in a scheme or bailout that kept the Buckleys wealthy (though never as wealthy as outsiders thought).

The senior Buckley modeled far-right politics for his children. He was an ardent antisemite and segregationist, a supporter of Mexican dictator Porfirio Díaz, and an America First nationalist. The children joined him in these causes, the older ones burning a cross in a neighbor’s yard and vandalizing another neighbor’s church. (Buckley, who regretted being too young to join in the cross-burning, later shrugged it off as “the kind of thing we didn’t distinguish from a Halloween prank.”) Buckley showed his filial loyalty by becoming, as he described it, his father’s “echo chamber,” absorbing his worldview and parroting it back during dinnertime discussions and school debates.

What Buckley most inherited from his father, however, was a tangled sense of entitlement and exclusion, a belief that he deserved to rule but was denied his birthright, either because of his Catholicism or his conservatism. And Buckley did buck the consensus of his day, first around the New Deal, then U.S. entry into World War II, then the liberal postwar order. Among the elites in Connecticut, at boarding school, and then at Yale University, Buckley stood out as a right-wing iconoclast. No wonder he developed an attraction to his favorite philosopher Albert Jay Nock—a regular dinner guest at the Buckley home—and to Nock’s idea of the Remnant, a tiny minority standing against the tide of modern liberalism.

But as it turned out, no door was actually closed to Buckley. At Yale, where he was unknowingly part of a quota on Catholic and Jewish students meant to limit their numbers on campus, he quickly became the elite of the elite, elected as chairman of the Yale Daily News, inducted into the secret society Skull and Bones, and chosen for the prestigious Class Day speech. He turned that speech into a bestselling book, subsidized by his father, while doing a stint with the CIA. Mountains of speaking invitations followed, establishing Buckley’s national fame, which he used to assemble a group of donors and launch National Review in 1955.

That meteoric rise was built on the notion that in a time of liberal conformity, there were things that could not be said, and Buckley alone dared to say them. But in fact, Tanenhaus reveals that Buckley regularly won plaudits for his brash claims, impressing even the people he failed to persuade. “I don’t see eye to eye with you on some pretty important matters, specifically your anti-democratic authoritarianism,” a liberal Yale professor wrote to Buckley after a speech he delivered as chairman of the Daily News. But he was still wowed by the young ideologue. “You managed to state your convictions, on an occasion that must have seemed to many of your listeners very inappropriate for such a pronouncement, with great directness, sincerity, and humility.”

Buckley’s ability to forge friendships and loyalties across political divides kept him in good standing with American elites and their institutions, no matter how right-wing his ideas. He could cheer Joe McCarthy and investigations into suspected communists, argue for segregation and Black disenfranchisement, defend the white police officers at Selma, argue gay men with HIV/AIDS should be forcibly tattooed, participate in the Watergate coverup, and even publish a fraudulent article to try to discredit the Pentagon Papers, and still his star rose, and rose, and rose. Tanenhaus credits Buckley’s ability to draw “a sharp line between his ideological commitments and his social life.” But his ascent also relied on his critics’ ability to do the same. Buckley was, after all, one of the elite; his radicalism thrilled them. And perhaps it was not so radically different from their own view of the world.

When U.S. historians began to give sustained attention to the conservative movement in the late 1990s and early 2000s, no figure loomed larger than William F. Buckley Jr. For years, National Review sat at the heart of histories of the respectable right—and histories of the respectable right sat at the heart of histories of conservatism. Tanenhaus, having just published his magisterial biography of Soviet spy-turned-anticommunist writer Whittaker Chambers in 1997, began working on Buckley the next year, at the very moment that historians were contemplating him as a pillar of the conservative intellectual movement.

Neither Tanenhaus nor his fellow historians remained captive to that moment, however. Over the last decade or so, historians have spent more time exploring the connections between the far right and the more mainstream right, questioning whether the difference between them is one of kind or degree—or, put another way, one of genuine ideological difference or of rhetorical performance and political posturing. Buckley has remained a central figure in that debate, with a reputation that has shifted alongside the historiography: as an intellectual innovator who fused the disparate strands of Cold War conservatism, as the person most regularly credited with purging the kooks from the movement, and as the author of one of the most notorious segregationist tracts published in a national magazine, his 1957 column “Why the South Must Prevail.”

Tanenhaus benefited greatly from this rich new body of scholarship, which informs his biography even as it limits the novelty of his revelations. (There are now entire books and documentaries dedicated to Buckley’s friendship with killer Edgar Smith, his combative relationships with Normal Mailer and Gore Vidal, and his Cambridge Union debate with James Baldwin.) Drawing from these new works, Tanenhaus jettisons the older depictions of Buckley as erudite intellectual and restrained movement leader. His Buckley is more a performer than an intellectual, less interested in advancing ideas than in winning debates. “He might or might not be the best new conservative writer and talker,” Tanenhaus writes of Buckley’s meteoric early career, “but he was fast becoming [the movement’s] most entertaining—and possibly represented a new kind of public figure: not precisely a journalist or commentator or analyst but a performing ideologue.”

As an ideologue rather than an intellectual, Buckley happily shed facts when they were inconvenient, making up more useful ones as he went. Such was the case when he spoke about the events in Selma, Alabama, on Bloody Sunday in 1965, when white police officers beat peaceful Black protesters. Speaking before a group of New York police officers, Buckley admitted there were “excesses” on the part of the police in Selma, but lamented that no one dared criticize the excesses “of those who provoked them beyond the endurance that we tend to think of as human.” The protesters, he said, had incited the officers for “twenty long minutes, 1200 seconds freighted with tension.” Except there was no provocation, only officers and Klansmen armed to the teeth, facing unmoving marchers and journalists, who had been given just two minutes to clear out before the police attacked.

Those lies cost Buckley nothing. In fact, they launched his quixotic bid for New York City mayor in 1965, which launched his television show, “Firing Line,” in 1966, a show that ran for more than three decades.

Tanenhaus does credit Buckley with attempting to purge the John Birch Society from the conservative movement in 1965, after it had become so tarnished as a far-right organization that Buckley believed it had outlived its usefulness. (And anyway, Buckley thought the society had the wrong analysis; the problem wasn’t communists, it was liberals.) But Tanenhaus makes clear that it was a calculated move arising not from Buckley’s rejection of extremist ideas, but rather his pragmatic calculations about what was in the best interest of the movement—and of his own career. After the highly publicized rift, he reached stratospheric new heights. “It added luster to his own standing as the respectable ‘ultra,’” Tanenhaus writes. “He was now highly marketable.”

There seemed to be nothing that could damage Buckley’s marketability. Not queer-baiting Gore Vidal in national media, not helping free a convicted murderer who then attacked another woman, not violating antifraud law so egregiously that he was slapped with an unusually high $600,000 fine. Buckley had secured his place among the elites, and in the United States, elites are loath to hold their own accountable. Especially when their own throw lavish parties at their Upper East Side maisonette and their country estate in Connecticut.

In return, Buckley was fiercely loyal to those he counted as friends. Indeed, loyalty rather than ideology was the best predictor of Buckley’s actions. It was loyalty that drew him into a curious and alarming relationship with killer Edgar Smith; that led him to donate to a liberal antiwar Democrat to help him win a House race; that encouraged him to stand by Howard Hunt, one of the main players in the Watergate break-in, even though it meant concealing from investigators the extent of the cover-up, which Buckley knew early on led straight to the Oval Office. That loyalty seemed to have limits only when it interfered with Buckley’s self-interest—Tanenhaus shows that on at least two occasions, Buckley cribbed from other writers, including one of his own, Garry Wills. (Buckley edited Wills’s review of The Fire Next Time for National Review, then wrote a column that cribbed so heavily from the piece that Wills told Buckley it “suggests some interesting reflections on your conception of editing and/or plagiarism.”)

That loyalty, though, was particular, and never penetrated Buckley’s worldview. If his friendships were safeguarded from his ideology, so too was his ideology safeguarded from his friendships. So he railed against the death penalty for Edgar Smith while making it a core part of his law-and-order politics; surrounded himself with gay friends while mocking the AIDS epidemic and lashing out against Gore Vidal’s queerness; and pleaded mercy for Howard Hunt while denouncing corruption in government. This schism between friendship and philosophy was hardly unique to Buckley. But in a leader of modern conservatism, such a worldview was a red flag. As a governing philosophy, it trod dangerously close to that of Peruvian fascist Óscar Raymondo Benavides: “For my friends, everything; for my enemies, the law.”

The Buckley that Tanenhaus reveals—the racism and antisemitism, the aggrieved inclusion in the elite, the fake news and made-up arguments, the performer’s instinct, even the corrupt financial dealings—invites reflection on the movement Buckley built and its relationship to contemporary politics. Buckley deserves to be read as more than just a preview of Donald Trump; Tanenhaus’s careful excavation of Buckley’s life smartly avoids trying to make any claims about the current catastrophes unmaking American government. But this fine-grained and insightful biography also illuminates how easy the transition was from Cold War conservatism to Trumpism.

Buckley was a master of the media ecosystem of his day, his untraceable accent and odd mannerisms captivating audiences who tuned in for political clashes. He understood that debate was about performance, and felt unrestrained by facts or truth. He felt comfortable around antisemites and fascists, and provided cover for Chilean dictator Augusto Pinochet. He intuited white discontent about Black progress and helped shape the backlash politics that followed. He broke the law, paid his fine, and walked off otherwise unscathed. He moved comfortably among the American elite while practicing a politics that named them as the enemy. He prized loyalty above all else.

The comparison need not be strained; Bill Buckley was not Donald Trump. His magazine opposed Trump’s 2016 presidential run and has settled into an uncomfortable anti-anti-Trumpism. But by the end of Tanenhaus’s biography, the arc of the conservative movement from the Cold War days when Buckley was at his height to the present is no longer so mystifying, the transformation no longer so sharp.

Buckley doesn’t cover the latest transformations within the American right, ending instead with Bill Buckley’s death in 2008. His funeral, Tanenhaus notes, featured two former Democratic presidential nominees: John Kerry, who like Buckley had been a member of Skull and Bones, and George McGovern, who had regularly debated Buckley in the years before his death. His ability to charm even the people who most opposed his politics spoke to something unusual about Buckley, a trait that leads Tanenhaus to the one odd note of his book, a closing call to channel “the imagination and generosity, the kindness and warmth, that Bill Buckley demonstrated time and again in his long and singular life.” Having lived with Buckley as a subject for nearly three decades, Tanenhaus himself gives into that charm in the closing sentences of his biography. But Buckley offers the portrait of an activist and writer far more complicated—with a legacy far more ambivalent—than that ending suggests. Which is, in the end, what makes it such a remarkable, timely, and provocative book.