George F. Kennan, ed. Frank Costigliola, The Kennan Diaries (New York: W. W. Norton & Company, 2014), 768 pp., $39.95.

A FRIEND RECENTLY described me in an email as “irascible.” She meant it in an offhanded, affectionate sort of way—but I have to admit that her choice of adjective gave me a chill. Could it be that, unnoticed to myself, I had slipped into the ranks of the most tiresome group of people in the United States? I refer, of course, to the Grumpy Old White Guys. You know the type. They’re the ones who corner you at a party to complain about the use of Spanish in official announcements on the bus, or cut you off in the supermarket parking lot to compensate for early retirement-induced rage. Their public mascot is John McCain, that walking tantrum-in-waiting—but that doesn’t mean that all of them are conservative. To the contrary: you can also find plenty of crabby old liberals out there, griping about the collapse of manufacturing or the hopeless egotism of today’s materialist youth. (I’m actually pretty sure that cantankerous boomers represent a core demographic for Rolling Stone andthe New Yorker.) It’s gotten to the point where I automatically steer a wide berth around any portly, bearded over-sixty wearing glasses on a lanyard.

I’ve tended to think of this as a strictly contemporary phenomenon, along with Duck Dynasty, retiree Pilates and websites for Christian singles. How wrong I was. It turns out that the Grumpy Old White Guys actually have a venerable and quite august pedigree—and among them was one of the most influential American foreign-policy thinkers of the twentieth century. I speak of George F. Kennan (1904–2005), the man who provided the intellectual underpinnings of the Cold War concept of containment, who served as the first head of the State Department’s Policy Planning Staff, and who made vital contributions to the Marshall Plan as well as the design of overall U.S. strategy toward Europe and the Far East in the wake of World War II. He met with everyone from Joseph Stalin to Mikhail Gorbachev, from Harry Truman to Ronald Reagan. George H. W. Bush awarded him the Presidential Medal of Freedom. His friend Charles Bohlen, who served as ambassador to Moscow, wrote a fine memoir called Witness to History. But Kennan was truly it.

Few American public-policy intellectuals have been comparably lionized during their lifetimes. But Kennan deserved it. There weren’t many in Washington who could compete with his remarkable breadth of learning and experience, which included flawless knowledge of multiple languages, a deep immersion in the life of Central and Eastern Europe, and a silky and ironic prose style, modeled partly on Edward Gibbon, that reflected his intense, private engagement with the great Russian writers. He was a rara avis in Washington, a deeply cultured man who had an intuitive understanding of the European civilization that disappeared in August 1914. He never ceased mourning its disappearance, dedicating his last books to analyzing the diplomatic machinations of Germany, France and Russia preceding the plunge into the abyss.

UPON HIS graduation from Princeton University in 1925, where he never quite fit in, Kennan entered the State Department, where he was posted to Riga, Latvia. There he learned Russian and absorbed anti-Communist precepts. He never had any illusions about the thugs that surrounded Stalin, and he served as an aide to the first American ambassador to the Soviet Union, William Bullitt, who entered his post sympathetic to Soviet aspirations only to become a virulent anti-Communist after witnessing the depredations of Stalinism. Kennan went on to serve in posts in Berlin and Prague, where he saw the Nazi dictatorship firsthand. It would be difficult to think of anyone who had a clearer understanding of totalitarianism in the past century. Kennan may have been somewhat maladroit as a diplomat—he was banished from the Soviet Union as ambassador after World War II for making the true but impolitic observation that the Soviet Union’s methods reminded him of those of the Nazis—but he was a remarkably clear-eyed observer. Indeed, it was his deftness as a writer that helped to magnify the impact of both his “Long Telegram” of February 1946, which warned about malign Soviet intentions and arrived like a thunderbolt in official Washington, and his July 1947 Foreign Affairs article “The Sources of Soviet Conduct,” which, appearing under the pseudonym of Mr. X, posited that “the main element of any United States policy toward the Soviet Union must be that of a long-term, patient but firm and vigilant containment of Russian expansive tendencies.” It neatly summarized the future of Cold War strategy, setting up a lifelong, agonized confrontation between Kennan himself and the policy that he had helped to birth. A national-security state, which engorged itself on massive budgets and perpetual enemies, had emerged, and Kennan viewed it as wholly inimical to true American republican traditions, a trend that was confirmed once neoconservative triumphalism about the end of the Cold War morphed into a global crusade to crush America’s real and imagined foes.

Despite his obvious intellectual integrity, Kennan retired from the State Department at the age of forty-nine—if “retired” is really the right word to use. (He was actually frog-marched to the exit by the baleful John Foster Dulles after Kennan dared, in one of his public talks, to repudiate the idea of the rollback of Communism in Eastern Europe as “replete with possibilities for misunderstanding and bitterness.”) The author of containment soon ended up at the Institute for Advanced Study at his alma mater of Princeton. There, he cemented his reputation by churning out a string of histories, memoirs and analyses that brought him two National Book Awards and two Pulitzer Prizes (as well as an Einstein Peace Prize, in recognition for his passionate opposition to the Vietnam War and the nuclear-age balance of terror). It quickly became clear that Kennan was the supreme realist, almost always skeptical of America’s intentions and ability to effect beneficent change abroad. In 1957, when he delivered the Reith Lectures at Oxford, he caused an international stir by advocating that the West work toward a neutral and unified Germany. He wanted cooperation, not confrontation, with Moscow. He was denounced by Dean Acheson as espousing delusional pacifist views. But Kennan was the wisest of the wise men, a profound thinker who had a tragic sense of history, particularly in the atomic age, that his coevals lacked. He despised the assumption, still embarrassingly common among American politicians, that all you need to get a foreign leader to come around to Washington’s position is a bit of personal quality time (just think of Clinton’s sauna sessions with Boris Yeltsin or George W. Bush’s notorious soul gazing with Vladimir Putin). Kennan believed that foreign policy should be based on a sober assessment of national interest, not on the caprices of personality or temporary political advantage. At a moment when much of the foreign-policy establishment was championing war with Iraq in 2002, Kennan, at the age of ninety-eight, vigorously decried the notion that it would end in anything but disaster. “Today, if we went into Iraq, like the president would like us to do, you know where you begin,” he said. “You never know where you are going to end.” He was right. All his life he liked to quote Gibbon’s passage in The Decline and Fall of the Roman Empire about the “unnatural task of holding in submission distant peoples.” Not until 2005, when he died at the age of 101, was his perspicuous voice stilled.

THAT WAS THE public Kennan. But it turns out that there’s a lot more to the story. The man who reveals himself in The Kennan Diaries is a compulsive grouser, relentlessly downbeat about his personal prospects as well as those of his country, tormented by his nagging attraction to women not his wife, plagued by intense loneliness, bedeviled by a sense of his own inadequacy and grimly obsessed with the extent of his clout. He was an unapologetic reactionary. It was his neighbor J. Richardson Dilworth who put his finger on Kennan’s personality: “George is ultra-conservative. He’s almost a monarchist.” Kennan was the ultimate realist about the country that he alternately loved and loathed. Like Henry Adams, with whom he had much in common, he never fully trusted it. He viewed democracy itself with profound misgivings, contemptuous of gusts of public opinion, embodied in the Red Scare and the rise of McCarthyism, that could buffet foreign affairs and prevent elites from calmly steering the ship of state. Like Acheson, he viewed apartheid South Africa with indulgence and the lower orders with mistrust.

To be sure, we’ve caught glimpses of this Kennan over the years—like this brief bit of 1952 self-analysis in the second volume of his memoirs, where he berates himself for his abortive stint as ambassador to the USSR:

I was probably too highly strung emotionally, too imaginative, too sensitive, and too impressed with the importance of my own opinions, to sit quietly on that particular seat. For this, one needed a certain phlegm, a certain contentment with the trivia of diplomatic life, a readiness to go along uncomplainingly with the conventional thinking of Washington, and a willingness to refrain from asking unnecessary questions—none of which I possessed in adequate degree.