On a hot, dusty Sunday in September 1959, George Frost Kennan welcomed to his Pennsylvania farmhouse a peculiar trio of political intellectuals. Trekking out to see the retired diplomat and renowned Sovietologist on that Labor Day weekend were the German-born psychologist Erich Fromm, the sociologist David Riesman, and Norman Thomas, the perennial Socialist Party nominee for president. Their agenda was the creation of a new socialist party for the United States.

“What a strange quartet we were,” Kennan remarked in wonder. The “brilliant, subtle, and hugely imaginative” Riesman, he rightly observed, had never been enchanted “by the waning power of Marx’s magic spell”; but more to the point, Kennan himself “had little sympathy ... with the inherent self-pity of the socialist cause.” As Kennan recorded in his diary that day, Burke, Gibbon, and the nineteenth-century Russian novelists shaped his own thinking much more than any left-wing thinkers ever had. “All my Scottish-Protestant antecedents rose in protest against this egalitarianism,” he wrote. “This really wild belief in the general goodness of man, this obliviousness to the existence of original sin ... this grievous Marxist oversimplification of the sources of aggressiveness and bad behavior in the individual as in the mass”—it was all too naïve and wooly-minded. Predictably, the attempted meeting of the minds ended in incoherence, thrusting Kennan back into what he called “the organizational isolation where, evidently, I belong.”

This vignette is one of many gems in Kennan’s fascinating and damaging journals, now edited by Frank Costigliola, a skilled historian of American foreign relations, and it highlights a riddle of Kennan’s life: his policy ideas were utterly central to the foreign relations of the United States in the twentieth century, but he had no real home in its political system. Normally a supporter of Democrats—in the diaries, he voices support for the presidential bids of Adlai Stevenson, John F. Kennedy, Eugene McCarthy, Frank Church (“promptly regretted it deeply”), and Bill Clinton (“without enthusiasm”)—Kennan was nonetheless profoundly conservative in his worldview. This conservatism was neither the belligerent cultural populism bequeathed to today’s Republicans by Richard Nixon nor the happy hawkishness championed by Ronald Reagan (both of whom Kennan abhorred). It partook, rather, of Burke’s chastened view of human nature, and of the declinism of Gibbon, and of the Social Darwinism of Herbert Spencer and William Graham Sumner—often manifested, in Kennan’s case, in casual and appalling prejudices. Above all, it echoed the brooding anti-modernism and civilizational despair of Henry Adams, to whom, fittingly, Kennan likened himself in the winter of his life. The architect of the policy of containment, it turns out, crafted the policy in defense of a country he never much liked, filled with citizens he by and large despised....

or the student of American foreign policy, Kennan’s accounts of dealing with his Russian counterparts, his arguments about strategy in the Korean War, and other such material all add up to a tremendous historical resource. But in the latter half of Kennan’s life, when his interactions with power were fleeting and usually ceremonial, what dominated the journals were heavy ruminations about life, career, and humankind. Sometimes these are provocative, sometimes petty, and over seven hundred pages they grow wearisome. Curiously, Kennan himself had a similar impression. “I have been reading over the diary entries from 1964-1984, and have derived little pride or satisfaction from the effort,” he writes in 1987. “Where they were not personally plaintive, they tended to be repetitive.”

What spoils the tedium, what compels fascination despite the monotony, are the astonishing outbursts of bigotry and misanthropy. Apparently, the value of these splendid rants against all manner of ethnic groups was lost on William Shawn, who by then had left The New Yorker and was an editor at what Kennan calls “the very Jewish firm of Straus & Farrar.”

Having been shown the diaries for possible publication, Shawn told Kennan’s (very Jewish) agent Harriet Wasserman that Kennan’s “German problem”—something of a cryptic phrase—was too toxic. Shawn appears to have been bothered that the journals were littered with disparaging comments about Jews and the Jewish people, although Kennan seems not to have noticed those asides in his own re-readings. “I have never been anti-Semitic,” he insists in response, with a breathtaking lack of self-awareness, “but I must admit that this episode brought me as close as I have ever been to becoming one.” (Ten years later he is still seeing Jewishness as only an anti-Semite would. “The scandal of Mr. Clinton’s relationship to his Jewish girl intern ...” one entry begins.) There is poetic justice in the likelihood that the publication of these diaries will do more to tarnish their author’s reputation than the publication of any collection of private writings since H. L. Mencken’s.

The diaries establish beyond any doubt that Kennan was given to gross and derogatory generalizations about virtually all foreign peoples. (Historians have known about Kennan’s ugly qualities, but the diaries lay it bare for any reader.) His belief in national character was strong, and if it led him to important insights about Russian behavior, much more often it led to repulsive and ill-informed slurs. The shockers start early. During his junior year at Princeton, he writes about a conversation with a friend called Army. “He half-converted me to his ‘extermination of the lower races’ idea,” Kennan writes. “I cannot see why it is wrong in principle.” As a twenty-eight-year-old Foreign Service officer, he remains convinced that the world’s problems are “essentially biological” in that “We have a group of more or less inferior races.... No amount of education and discipline can effectively improve conditions as long as we allow the unfit to breed copiously and to preserve their young.” Nor does Kennan learn, in his long globe-trotting career, to see this rubbish for what it is. At the age of eighty, he is still confiding to his diary his enthusiasm for eugenics. “If I had my way...” he muses, “Men having spawned more than 2 children will be compulsively sterilized. Planned Parenthood and voluntary sterilization will be in every way encouraged.” Policy planning indeed. (Immigration, too, “will be effectively terminated.”)...