This is a complete and fascinating biography of a man who lived a full, one-hundred-year plus life. Others more qualified than me have reviewed and praised this book, so there's not a lot that I can add. However, I will add this: Kennan was a complex and difficult character. He was often elitist and pessimistic. He seems to have been ridden with one illness or another (yet he lives, with his wits about him, to over 100!). But the one question that Gaddis doesn't answer or address as fully as I would like in this book: where did Kennan get his seemingly unique perspective of containment as a way to draw the line on Soviet expansion? Roosevelt and American liberals seem quite naive about Stalin and the Soviet system. But Kennan, writing from bed (ill again), sends his "Long Telegram" (later transformed into "The Sources of Soviet Conduct" by "X"). He alone seems to have articulated this very successful and insightful perspective about Soviet conduct and how to check it. Where did this come from? Well, he learned Russian as a young American diplomat He spent a good deal of time in the Soviet Union (two stints by the time he wrote his fame-producing article in 1946). And he read Gibbon while on a vacation. Gibbon helped form his sense that the Soviets would not be able to "digest" their land grab in Eastern Europe, Kennan thereby proved himself a prophet by about 1989. No, it doesn't appear that Kennan had a "grand theory" (a course Gaddis helps teach). It appears that Kennan developed his insights through patient observation and reading history. (I've failed to mention that Kennan seriously considered writing a biography of Chekhov.) Of course, after establishing the idea of containment, Kennan spent the next 40 years trying to keep it from misapplication as simply a crude military doctrine.
Quite a good book indeed, and quite a fascinating subject. At 698 pages of text, it's not a quick read. If you want a quicker sense of Kennan, turn to two works by his friend John Lukacs, their letters edited by Lukacs and Lukacs's biography. Both are briefer but insightful (and of course, Lukacs appreciates Kennan as both an actor and as a historian.)