Here is a picture of Gorbachev with Steve. Here is another picture of Gorbachev with Steve, this one with some Russian dissidents. And look, there is one of Gorbachev and Katrina, Steve’s wife, holding their infant daughter. There is even a Gorbachev magnet on the refrigerator.

Walking around this book-lined apartment on Manhattan’s Upper West Side on an August evening, it is almost as though the man with the world’s most famous birthmark is the third partner in the marriage of Stephen F. Cohen and The Nation editor-publisher Katrina vanden Heuvel.

For more than four decades, Cohen has been a leading voice on Russian affairs, pinballing between the academy, where he is now emeritus at Princeton University and NYU, and the media, influencing world events along the way. Few scholarly works can be said to have equaled the direct political impact of Cohen’s 1973 biography of the Soviet founding father Nikolai Bukharin. Bukharin and the Bolshevik Revolution (Alfred A. Knopf) didn’t just suggest a new understanding of the Russian Revolution when it was released in the middle of the Cold War — it profoundly affected the course of that war. Mikhail Gorbachev’s chief foreign-policy adviser, Anatoly Chernyaev wrote, “Some of us had already read the book, and we encouraged Gorbachev to do so. He took the book on vacation with him. He read it closely and kept quoting it to me. … The re-evaluation of Bukharin’s role and personality opened the sluice gates to reconsidering our whole ideology.”

Gorbachev’s affection for Cohen’s ideas — and for Cohen himself — turned a lowly scholar of the Russian Revolution into an intellectual VIP who sat in meetings with heads of state. Eric Alterman, a journalism professor at Brooklyn College and a Nation columnist who has known Cohen for decades, calls Bukharin and the Bolshevik Revolution “one of the most consequential books of the past century.” It realized “the dream of all writers to have an effect not only on world leaders but also on history itself.”

But these days, Cohen is better known for his views on a different Russian leader. In his columns and media appearances in recent years, he has become perhaps the most prominent defender of Vladimir Putin. “Putin is not a thug,” he declared on CNN. “He’s not a neo-Soviet imperialist who’s trying to recreate the Soviet Union. He’s not even anti-American.” The defense extends to the U.S. president, who has had some nice things to say about Putin. “The number-one threat to the United States today,” Cohen told Fox News, is the continuing investigation of Trump’s ties to Russia: “There is no evidence there was any wrongdoing.”

Perspectives like that have attracted the ire of a wide array of critics. Writing in The New Republic, Isaac Chotiner called Cohen “Putin’s American apologist.” Jonathan Chait in New York magazine labeled him a “dupe” and “a septuagenarian, old-school leftist who has carried on the mental habits of decades of anti-anti-communism seamlessly into a new career of anti-anti-Putinism.” Cathy Young in Slate said Cohen was “repeating Russian misinformation” and “recycling this propaganda.” And there are many others who share those views, even at the magazine his wife runs.

Cohen’s ideas about Russia, which once got him invited to Camp David to advise a sitting president, now make him the most controversial expert in the field. His enemies and friends ask the same question: What happened to Stephen F. Cohen?

When Bukharin and the Bolshevik Revolution was published, détente between the United States and the Soviet Union was well underway. But Russian studies was still dominated by the view that the Soviet Union was a totalitarian state, immune to reform because the logic of total control was embedded in the Soviet DNA. “The Western view [is] of Stalinism as the only outcome of Bolshevism,” Cohen wrote.

His book exploded that notion. It showed that Bukharin, a Marxist theoretician and member of the Russian Communist Party, offered a programmatic Soviet alternative to the Stalinism that eventually triumphed. “It was a huge statement,” says Eugene Huskey, a political scientist at Stetson University. Bukharin and the Bolshevik Revolution did what scholarly history should do: Use primary source materials to revise the understanding of the past. But it had obvious implications for the present and future as well. If the Soviet Union had become a tyrannical regime as an accident of history rather than as the inevitable end of a deterministic ideology, then perhaps reform was possible.

The book might have remained merely well regarded if not for Gorbachev. For those Russians looking for an alternative between capitalism and Communist dictatorship — and members of Gorbachev’s cabinet were foremost among those who were — Bukharin and the Bolshevik Revolution suggested one. “During the years of perestroika, many of my acquaintances were literally engrossed in reading his book,” Gorbachev wrote in an essay that was included in an anthology featuring 35 prominent Russian political, cultural, and media figures marking Cohen’s 70th birthday. “I remember that this book, which in many respects resonated with the social changes of that time, became a best seller in the Soviet Union.”

There was a brief, glorious period in the late 1980s when humane reform of Russia seemed possible, and Cohen was a hero to Gorbachev and his fellow reformers. He was seen as a man who offered an intellectual blueprint for a democratic socialism that could save Russia. Cohen visited Camp David at the request of President George H.W. Bush, squaring off against Harvard’s Richard Pipes in a scholarly battle to influence U.S. foreign policy and determine the course of the Cold War. He wrote frequently for The New York Times, almost leaving Princeton to become the newspaper’s Moscow correspondent.

But that was decades ago. Gorbymania is passé. Now it’s Putin. Putin, Putin, Putin. And Cohen is not friends with Putin, though he downplays the Russian leader’s failings. Presidents are no longer interested in the opinions of Cohen. But at least he can do his best to ensure that what he has for years been calling a second Cold War does not become a hot war. Cohen thinks we are closer than we have ever been, closer than we were during even the Cuban missile crisis or Able Archer. And the idea that he is unable to stop the downward spiraling of U.S.-Russian relations is nothing short of agonizing. A nuclear war between Russia and the United States is his biggest fear. (Well, that and irrelevance, if you believe his critics.)

Not that any such anguish is immediately evident when we meet in his apartment. He’s from Kentucky, he says, and retains “a skepticism about everything except horses and bourbon.” Dressed in jeans and a black-and-gold shirt, he smokes Marlboros on his living-room couch. The view of Central Park from here is of green treetops at sundown. At 78, he is still handsome, with a full head of salt-and-pepper hair. Vanden Heuvel, who walks in and out of the room, is 20 years younger and looks like a dark-haired heroine out of Tolstoy.

Cohen spends much of his time writing for The Nation. Their daughter, Nicola, who is here for dinner tonight, attends Columbia Law School, going into criminal-justice reform. Which, if you had to guess what a child of Cohen and vanden Heuvel would be doing with her life, is pretty much what you would come up with. “I’m very proud talking about my daughter’s passion for justice,” he says, listing off her accomplishments. It’s not a bad life.

But the attacks in the media have stung. Vanden Heuvel can recite the worst of them. And they have also started to come from inside The Nation, where editors and reporters wonder if Cohen’s influence is responsible for the country’s leading left-wing magazine taking the side of Donald Trump and Vladimir Putin on U.S.-Russia policy.

In academe, Cohen gets more regard. He has a chest of good will stored away, for his Bukharin biography primarily, but also for his essays on Russian history, collected in books like Rethinking the Soviet Experience (Oxford University Press, 1985) and Soviet Fates and Lost Alternatives (Columbia University Press, 2009). “He’s well-respected as a sort of historical political scientist,” says Ronald Suny, a Russianist at the University of Michigan.

But even among fellow scholars, things have changed since Cohen emerged as the foremost public intellectual pushing back against accusations that Russia helped elect Trump. He has appeared on shows like Tucker Carlson’s on Fox News and called Trump “politically courageous” and “demonized” for trying to establish good relations with the Russians. “He’s gone from being a terrific Soviet historian to a commentator, to [talking] more about U.S. policy debates and what he sees as the corruption of those debates. But that isn’t his academic field; his contributions aren’t scholarly,” says Stephen Sestanovich, a Russia expert at Columbia.

“I would say he’s not in the mainstream,” says Huskey. “He’s clearly an outlier” in absolving Russia for its military excursions and electoral interference. “Many have the perception that his comments make him out to be an apologist for Russia.”

That perception has tarnished Cohen’s name. In 2014, vanden Heuvel initiated discussions with the Association for Slavic, East European, and Eurasian Studies on funding a dissertation fellowship named after Cohen and his mentor, Robert Tucker. But the association delayed approving the fellowship when some board members complained about establishing one with Cohen’s name. Stephen Hanson, the group’s president at the time, told The New York Times, “It’s no secret that there were swirling controversies around Professor Cohen. In that context, consulting with a wider community of scholars was the prudent thing to do.”

Cohen and vanden Heuvel withdrew the offer. The association later asked if the couple would take Cohen’s name off the fellowship but still provide funding, a request that further insulted them.

In January 2015, David Ransel, an Indiana University professor and former editor of the American Historical Review, wrote a letter to the association, saying that its handling of the matter “reeks of a censuring of public discourse and should be regarded by all decent people as a profound embarrassment to our association.” It was signed by more than 60 scholars. A few months later, the group finally approved the Cohen-Tucker Dissertation Research Fellowship Program, which is still in existence.

The affair left Cohen dismayed. “I went ballistic,” he says. Vanden Heuvel calls it “a poke in the eye.” Cohen thinks that young scholars are afraid to voice views similar to his. He says he gets email to that effect. “They’re going to be careful. And you can’t be a good scholar and be careful.”

On a Tuesday evening, Cohen arrives at the WABC studios in midtown. He appears weekly on The John Batchelor Show, a talk-radio program, for a 40-minute discussion, highlights of which are summarized on The Nation’s website. He sports a light beard (the legendary Russian poet Yevgeny Yevtushenko once called Cohen’s facial hair a “rusty, biblical unshaveness”), and he smokes from a vaporizer on the elevator up to the studio.

Winding our way through the halls, he brings up several times appearing on the show with Oliver Stone to discuss Putin. “It was shown all over the world,” he says. For his segment, a giant image of Putin is displayed on the studio wall. Cohen, fluid and articulate, is comfortable here, cracking jokes with the host. He was a CBS commentator during the 1980s and appeared regularly on television. His smooth, deep voice, the product of decades of cigarettes, is made for broadcast. Vanden Heuvel shows up and lovingly takes a few photos of Cohen before scrolling through her emails.

He similarly blames America for panicking about Russian interference in the 2016 U.S. presidential election. “Why did America embrace what is clearly, or seems to be, a fiction for which there is no evidence?” He speculates on the answers: Putin was an obstacle to global American hegemony. Another scenario: “Sinister forces, greedy forces, high in our political system and in our economy, need Russia as an enemy because it’s exceedingly profitable.” U.S.-Russian relations “didn’t go wrong in Moscow.” They “went wrong in Washington.”

Not many scholars concur with those views. But even those who think Cohen is wrong now have to acknowledge that he has been right about a lot in the past. In addition to his views in the 1970s on the possibilities of Soviet reforms, he was proved correct in his assessment in the late 1980s that Gorbachev was a genuine democrat, in contrast to those who, like Richard Pipes, believed he was merely a kinder, gentler Soviet apparatchik. In the 1990s, Cohen was among the first to identify Boris Yeltsin as someone doing deep damage to Russia through his corruption. “Much of the academy were pro-Yeltsin,” recalls Suny. And Cohen was prescient in observing that post-Cold War NATO expansion would revive Russian nationalism.

Suny says Cohen “tries to fight all windmills at once” but adds that he is “rather courageous” and “covers for more timid colleagues” in countering the standard U.S. narrative about Russia. Robert Legvold, a Columbia University political scientist, says serious Russian experts “see him as wrong, but not as a traitor.” He notes, “Anybody who thinks he’s a tool of the Soviets or Russia is a fool.”

Vanden Heuvel offers her own frame: “If you have to define Steve, he’s an alternativist. This idea of don’t accept — seek the alternative.” Cohen’s views have made life difficult not only for him but also for vanden Heuvel. With his support of Putin and Trump (at least on Russia) “now there’s double toxicity” regarding him, as he puts it.

Staffers at The Nation are openly revolting against the magazine’s pro-Russian tilt. “There is a widespread feeling that he has always been involved and had lots of influence on vanden Heuvel, but that it ratcheted up with [the Russian invasion of] Crimea,” says the longtime Nation columnist Katha Pollitt. “He has a view that we are on the edge of World War III, and it’s not a view that I or other people hold.”

Vanden Heuvel points out that Cohen’s tenure at The Nation preceded hers and finds claims of his control over her insulting. But it is undeniable that the flagship magazine of the American left supports the Russia policy of Donald Trump. In June, some Nation writers told vanden Heuvel in a letter that “the magazine is not only playing into the hands of the Trump administration, but doing a dishonor to its best traditions.”

Cohen is insouciant about the controversy, except insofar as it hurts vanden Heuvel. His time working with Russian dissidents in the 1970s and 1980s inspired his nonchalant attitude. “There’s no real price for dissent in America compared to what it was in the Soviet Union,” he says. “I’m emeritus at two universities. That means I’m old and I got a lot of health care. What are they going to do to me?”

But the flashes of defiance can’t obscure the heartbreak. The tragedy for Cohen is that Gorbachev’s democratic Soviet alternative never materialized. Instead he lost control of the Soviet empire, and Yeltsin came to power, dissolved the Soviet Union, and oversaw a transition to a country based on hyper-capitalism devoid of the rule of law. And then Yeltsin selected Putin as his successor. None of the rest is history.

As I left their apartment, Cohen gave me a copy of his book The Victims Return (PublishingWorks, 2010), about survivors of Stalin’s gulags. On the train ride home, I looked at the inscription he wrote inside:

For Jordan —

Wishing you a happier fate.

Steve

Jordan Michael Smith is the author of the Kindle Single Humanity: How Jimmy Carter Lost an Election and Transformed the Post-Presidency. His writing has appeared in The New York Times Magazine, The Washington Post, and The Atlantic.