‘I am now of an age when I should, on all actuarial probability, have left this life,’ George Kennan wrote in his diary on 10 June 1983. ‘I must learn to look at [life] as a disembodied spirit.’ Over the course of his 101-year life, the author of the ‘X’ article – which made him the father of containment – filled 20,000 diary pages of elegant prose. His was the life of ‘an organic conservative’. Two other conservative figures come to mind, George Ball and Dean Acheson, but Kennan was certainly the most scholarly, perhaps the most querulous and easily the most self-absorbed. There were also times when he could be surprisingly self-critical. He had an elective affinity, after all, for Russia and retained it all his life. In a diary entry he confided, ‘my Russian self is much more genuine than the American one’. Even in the coldest days of the Cold War this affinity allowed him to cut against what the poet William Carlos Williams called the ‘American grain’.

Otherwise Kennan was anchored to the American past. He remained to the end a Calvinist in spirit, critical of China in 1979 for lacking the ‘capacity for pity and the sense of sin’. He never felt much sympathy for the Third World. It should look, he wrote in the same year, to the example of the early American settlers like his great-grandparents in Wisconsin: ‘it will have to work its passage as did our own forefathers or the passage will not be made’. He was critical of the Vietnam War but felt little sympathy for the student Left, which he saw as the product of an urban life that Jefferson had berated as ‘pestilential to the morals, the health and the liberties of man’. What should someone do in the face of developments which reveal that his own beliefs are running not only against the American grain, but also against the grain of history?

Kennan grew more pessimistic with the years, though this hardly seems to have been the product of a dyspeptic old age. Perhaps it was partly informed by the disappointments of his diplomatic career: his failed ambassadorship to the Soviet Union, his rejection by John Foster Dulles, his brief ambassadorship in Belgrade in the early 1960s. Academic life at Princeton never really compensated, though he did better than most professional academics by winning two National Book Awards, two Pulitzers and the Bancroft Prize. Perhaps it was the fact that he fell out of step with history; reading these pages, I was reminded of Susan Sontag’s remark that ‘devotion to the past’ is ‘one of the more disastrous forms of unrequited love’.

But then pessimism was part of his persona. ‘There comes a time, with the passage of the years, when one can love only small children. There is no love more certainly transitory than this,’ he writes on 4 August 1951. ‘I’ve often returned home in a state of depression but never anything like this before,’ he writes on 21 August 1968; he was now determined ‘to avoid all further confrontations with American life’. Nine years before he died he recalled a graffito ‘affixed to a religious placard somewhere in England consisting only of the words “Jesus Saves” to which some irreverent person (or was it really a reverent one?) had added the words “Jesus is tired. Save yourself.”’

His pessimism deepened with time. He had little faith in Nelson Mandela, seeing nothing in South Africa’s future but, he noted in February 1990, a ‘desperate attempt at emigration on the part of the whites, and strident appeals for American help from an African regime unable to feed its own people from the resources of a ruined country’. He thought the Soviet Union’s collapse had been too fast for any good to come of it. Even the space shuttle disaster in 1986 left him cold. He grieved at the death of the crew members but not their sacrifice, because he had no enthusiasm for taming the last remaining frontier.

But there was also another Kennan, of course, the one we know: the elder statesman who had an almost Bismarckian grasp of international politics. He recognised the progressive disintegration of the Soviet Union and saw in Gorbachev ‘a man of ideas and a very courageous one, but not a good administrator and … anything but an effective demagogue’. He produced a quite remarkably detailed critique of Bush’s decision to send US troops to Somalia in 1992 and he lived long enough to witness the folly of the invasion of Iraq 11 years later. How he must have despaired at the neoconservatives for their cultural philistinism and historical myopia. But then, unlike them, he knew the world: he knew Latvia back in the 1920s, when it still bore the imprint of imperial Russia; Geneva during the heyday of the League of Nations; Moscow before Stalin’s purges; Oxford in the late 1950s; and Belgrade in 1962. Back then he was at his most imaginative, promoting the reunification of Germany as early as the 1950s; recommending a 50 per cent reduction in nuclear arms 20 years later; constantly exhorting his own government to mitigate the great dangers of the Cold War.

These diaries fill 12 boxes of his collected papers, now available in the archives of Princeton. Many of the entries are self-consciously ‘poetic’; others exude purple prose; there are even some forgotten travelogues inspired by Alfons Paquet, a now forgotten German writer from the 1920s. I was reminded of John Updike’s magnificent creation Harry Angstrom, who in his own way is as angst-ridden as Kennan. In Rabbit Redux Harry feels he has come to the end of the American Dream; by the end of Rabbit is Rich he feels ‘the great American ride is over’. By the end of the last novel, Rabbit at Rest, he concludes that the ‘whole Free World is wearying out’. Updike went to his grave complaining that, with the end of the Cold War, America had lost its purpose. Kennan’s statesmanship in the early years of the war meant that the US survived it. The unrelenting gloom is that of a man out of step with the times; ironically, they would have been far more dangerous without him.