The first book to complicate the reputation of George Kennan came out in 1967. It was 600 pages long, and the cover would show a forlorn young man staring right at you. The tale was of an awkward boy from the Midwest who never quite fits in. He gains knowledge in the Foreign Service and becomes the United States' wisest Soviet analyst. Then, for a brief -- but crucial -- moment, he serves as the head of the State Department's Policy Planning Staff under President Harry Truman, helping remake the world after World War II. Along the way, he writes the "Long Telegram" and the "X" article, which laid out a strategy forever known as containment, and he plays a central role in designing the Marshall Plan. He writes beautiful memos that anticipate the dangers of keeping Germany divided and starting an arms race. But soon he grows irritated with Washington, and Washington grows irritated with him. He becomes as bitter as he is brilliant, as frustrated as he is farsighted. The story ends with him out of power, despairing for the republic. The book hints that its subject might be anti-Semitic, depressed, and professionally inept.

The author of that book, Memoirs 1925-1950, was Kennan himself, as self-critical and personally reflective an autobiographer as his century had seen. More books followed (including one by the author of this review), peeling back the onion further and further. Each new round of discovered documents and diaries has reinforced what was known before. And now there is John Lewis Gaddis' magisterial, authorized account, George F. Kennan: An American Life. It is based on intimate interviews with Kennan and access to all of his diaries, including the one in which he jotted down his dreams.

The Kennan who comes through in this new book is very much like the hero of Memoirs 1925-1950, only more so. He is wiser, and he broods more deeply. Kennan foresaw the arc of every major war of his lifetime. In 1940, he accurately predicted when the United States would engage Germany and how long it would take for his country to win; in the summer of 1950, he warned of giving too much power to General Douglas MacArthur in Korea; in 1966, he diagnosed the dangers of fighting in Vietnam and urged a dignified withdrawal. All the while, he wrote utterly scathing, and self-flagellating, notes to himself. Here is just one of several dozen diary entries that Gaddis cites: "There are times when I see myself as a spineless, somewhat infantile, futile little man." Brilliance and self-contempt always interlock with Kennan. In early 1949, at the height of his influence, Kennan, considering whether to resign, wrote to Secretary of State Dean Acheson that he had no enthusiasm for "the wretched consolation of having been particularly prominent among the parasites on the body of a dying social order, in the hours of its final agony." The same attitude manifested itself through the last 40 years of his life, when he was mainly a historian, essayist, and polemicist, declaiming against the folly of nuclear weapons.

As the book makes clear, he was never boring, and he was never bored. Kennan never seemed to pause -- even when he was ill, which he frequently was. Nearly every minute of his adult life was spent thinking about how to make himself, or his country, better. And there were a lot of productive minutes. He lived to 101 and published his last book when he was 96. In the mid-1950s, he wrote, "Men -- or at least such men as I -- are no good unless they are driven, hounded, haunted, forced to spend every day as though it were the last they were to spend on earth."

ARCHITECT OF CONTAINMENT

Kennan had two really big ideas. The first was containment, which he presented in the "X" article, published in Foreign Affairs in 1947, but which he had been refining for years in speeches. The idea was that there is a middle ground between diplomacy and war. If the former fails, the latter is not inevitable. The United States didn't have to remove the Communists from power in Moscow, and it didn't need to roll them out of Eastern Europe. It just had to wait, and eventually the Soviet order would collapse. The insight was heavily shaped by Kennan's study of The History of the Decline and Fall of the Roman Empire. Throughout his career, he would cite Edward Gibbon's statement that "there is nothing more contrary to nature than the attempt to hold in obedience distant provinces." The Soviets were overstretched, and communism was a wretched ideology. Washington just had to wait and quietly make Moscow's relationships with its clients as difficult as possible.

From almost the moment of the article's publication, policymakers were debating whether containment should be carried out through a series of political acts or through the threat of military force. Kennan had been ambiguous in this particular essay, but his speeches, other writings, and ­actions showed that his true preference was for the former. The article, however, was interpreted as mainly calling for the latter, and the United States' Cold War policy followed suit. This was a great source of stress for Kennan, and it left him with a complicated moral question after 1989. What do you do when your idea is misinterpreted -- in a way that you find repulsive -- but then leads to exactly what you hoped it would?

Kennan's second big idea wasn't original, but it was important. The word some political scientists use to describe it is "realism"; another way to put it is that Kennan was skeptical about American competence in foreign affairs. The United States, particularly when it did not follow his advice, could do little to change the world for the better. Given that, it was best to limit engagement and, when it was necessary to do something, to deal entirely with issues of power and interest. As he put it in 1951, he sometimes wondered whether American democracy was "uncomfortably similar to one of those prehistoric monsters with a body as long as this room and a brain the size of a pin." In 2002, as conflict in Iraq approached, he said, "War has a momentum of its own and it carries you away from all thoughtful intentions when you get into it. Today, if we went into Iraq, like the president would like us to do, you know where you begin. You never know where you are going to end."

Kennan recognized that his arguments were often futile and that presidents would rarely heed his advice. Containment turned militaristic, and every new administration would strut into office with ambitions to reshape the world. Still, he took solace in the notion that his ideas and books would live on. In a letter to Acheson, Kennan wrote that he wanted to be "one of those teachers whose teachings rarely please people, and are no doubt often wrong, but of whom it is sometimes said, when they are gone: 'It is useful that he taught as he did.' "

DEFINING THE DIPLOMAT

In September 1982, Gaddis sat down to interview Averell Harriman about Kennan. Gaddis, then just over 40, had written a letter noting that he was working on a Kennan biography and he wanted to do it fast. Might the former ambassador and governor be available to talk soon? Harriman agreed, although the book would not come out for nearly three decades. Gaddis had other things to write, and he wanted to wait on this big project until Kennan had died.

Now the biography has arrived, and it is terrific. Gaddis, a historian at Yale University who has published ten books on the Cold War, always writes well, but here he writes particularly well. The narrative moves quickly and smoothly. It also helps that Gaddis isn't trying to provide new Cold War scholarship. There's no slowing down to examine freshly discovered, and tangentially related, documents from the Soviet archives. Gaddis is just trying to tell readers about one extraordinary man. And it always helps one's prose to be able to pop in vivid quotes from one's subject.

Gaddis' take on Kennan is more or less the conventional one, which is partly because Gaddis has played a major role in shaping people's perceptions of Kennan in the first place. But there are surprises, one of the most interesting of which comes when Gaddis defends Kennan against charges of anti-Semitism. In his memoir, Kennan was strikingly callous in describing how he turned a Jewish acquaintance away from the Prague legation at the time of the German occupation; he followed this with a far more sympathetic description of a German prostitute whose husband was a Nazi pilot. Gaddis, however, notes that Kennan actually worked hard at the time to get other Jews out of Berlin and Prague. Kennan, it seems, was the rare man who implied that he was more prejudiced than he actually was.

The book is also particularly compelling when Gaddis describes Kennan's distance from his own nation. Kennan was born in the United States, he served his government, and he would have died for Old Glory. But he viewed the country with the eyes of a disgruntled visitor. In 1936, for example, Kennan wrote a profoundly weird essay, arguing, among other things, for the disenfranchisement of women, blacks, and naturalized citizens. At about the same time, he wrote rapturously about the system of social insurance set up in Austria -- apparently unaware that Franklin Roosevelt had passed something more robust right at home. His cultural knowledge was incomplete as well. In his diary in 1987, Kennan wrote of attending a dinner for Soviet President Mikhail Gorbachev and being seated at a table with "a lady of most striking appearance, who chain-smoked Danish cigars and appeared to be rather bored with the whole performance. . . . I was later told that I should have recognized her -- as the widow of a famous rock star." The star's name, he noted, was something like "Lenin." An American Life is an apt subtitle, but also a curiously ironic one.

Gaddis argues with Kennan a lot, and he doesn't romanticize his protagonist. He spends many pages exploring Kennan's infidelities -- which weren't particularly common but were still more common than one might have thought given the buttoned-up image that Kennan presented. Gaddis also expresses frustration that Kennan seemed to feel such a kinship for John F. Kennedy but such animosity toward Ronald Reagan. The former, Gaddis argues, appointed Kennan as ambassador to Yugoslavia but then ignored his recommendations. Reagan never hired Kennan for anything, but their feelings of revulsion toward the arms race were quite similar. After describing Reagan's efforts to remove nuclear weapons from Europe, Gaddis writes of Kennan, "How could he have loved John F. Kennedy, who repeatedly rejected his advice, and loathed Ronald Reagan, whose actions in this and other respects were consistent with it?"

Still, in the end, Gaddis praises Kennan highly. Kennan's most important idea, containment, "illuminated the path by which the international system found its way from the trajectory of self-destruction it was on during the first half of the twentieth century to one that had, by the end of the second half, removed the danger of great-power war, revived democracy and capitalism, and thereby enhanced the prospects for liberty beyond what they ever before had been."

KENNAN TODAY

The international system may now appear to be finding its way back toward the trajectory of self-destruction, and there is much that Kennan, were he still alive, would despair about -- foremost, perhaps, the grim prospects for liberty in Russia. The foreign policy of Barack Obama's administration, however, closely resembles the foreign policy one would reach after a close study of Kennan's views.

For starters, there is the gradual withdrawal from Afghanistan and Iraq. Kennan, as a good student of Gibbon, would have pushed for this drawdown to have started long ago, and he would certainly have supported it now. Combining withdrawal with targeted killings also seems like Kennan. He had his liberal side, but he was not squeamish. He cared little for the niceties of international law, and he did not fear the dark arts. He helped design the covert operations wing of the CIA and helped plan some of the agency's first secret escapades. In a way, the Obama administration has moved from a policy of trying to snuff out Islamic terrorism to one of trying to contain it. The stated goal is no longer to rid the world of al Qaeda; it is to limit the damage that it can do. The United States is no longer trying to wipe out the Taliban; it is talking to them.

Kennan loved rhetoric, and he would have felt a bond with Obama's use of words and his bookishness. Their speeches about the need to rid the world of nuclear weapons echo one another. But maybe more important, Kennan would have taken pleasure in this administration's abandonment of grand shibboleths. No longer does one hear the White House mentioning a "war on terror" or even a "war on drugs." Kennan believed that language helped make policy and that vague, expansive language would lead to vague, expansive policy. On these grounds, he opposed the Truman Doctrine. It sounded good to say that the United States would defend democracy anywhere, at any time. But there were many countries, he wrote, "where you could perfectly well let people fall prey to totalitarian domination without any tragic consequences for world peace in general."

Washington's change in discourse under Obama has also come with a change in attitude, and, no doubt, Kennan would have preferred the current president's humility to the swagger of George W. Bush or even Bill Clinton. Kennan would surely have criticized the main justification for international engagement in Libya -- he never much cared about human rights -- but he would have been glad that the United States let others lead the charge. When the country went to war against Muammar al-Qaddafi, it did so behind a genuine coalition. The uprisings in the Middle East have received only mild guidance from Washington. Kennan would have approved.

Or maybe he wouldn't have. As the book comes to a close, Gaddis seeks to portray the soul of the man he has been wrestling with for much of the past 30 years. In it, he finds "a profound uneasiness with complacency, or, to put it another way, a strong conviction that we -- whoever 'we' were at the time -- ought to be able to do better than this -- whatever 'this' might turn out to be." Kennan's was a spirit that could never be satisfied.

That trait helps explain why Kennan could never stop moving, and why he ultimately didn't have the political influence he wanted. But it also explains why he left behind so many ideas, and such a powerful example of how to live and think. It is useful that he taught as he did.