Fame, Rainer Maria Rilke said, is the sum of all the misunderstandings that grow up around a name. It has always been believed that Ken Clarke is the most sympathetic of Conservative politicians, a rare maverick, not given to cutting and trimming, and careless of his own fortunes. His reputation has been as a rough talker in a smooth party, the one human being in an otherwise inhuman outfit. Now aged 76, he has taken his chance to set the record straight by producing a book bent on proving that underneath his peacock selection of colourful hobbies – birdwatching, jazz, Formula One – he is, at heart, as orthodox and unchallenging as the smuggest of Soviet apparatchiks.

It’s hard to tell which depresses him more, poor guy: his own story, or the burden of having to speak it into a Dictaphone. (He leaves the actual writing to others.) Although he makes an unwise reference to Harold Wilson producing “impenetrable and unreadable books” about politics, it’s clear that it’s not in his own character to think too deeply about anything. Suspicious, he says, of anyone who flaunts their roots, he is happy nevertheless to stress that he is impeccably working class, born the son of an electrician who worked in a Nottinghamshire colliery.

His mother died in the 1970s of cirrhosis of the liver, but he disdains to go into details about the cause of the disease. “I don’t like to discuss these things at length because it is unfair on my mother and gives them more emphasis than they deserve.” Of his wife, Gillian, whom he met at Cambridge University, and who abandoned her own ambitions in order to be his helpmate, he remarks: “It quickly became obvious that Gillian’s intention of pursuing her academic career was fairly hopeless … She had, I would plead in mitigation, always known that I was going to be a professional politician.”

Proud of what he calls his “peculiarly laid-back and stress-free personality” and of having “the hide of a pachyderm”, he progressed from being president of the Cambridge Union to working as a jobbing barrister in Birmingham, and thence at the age of 30 to becoming an MP. After a spell as a whip for Ted Heath’s government in the early 1970s, he endured a period of opposition before what he calls “my boundless confidence in my own abilities” ensured that, after the Conservatives’ re-election in 1979, he achieved an 18-year run of power, smoking cigars and eating good meals at various high levels in Transport, Health, Employment, Trade, Education and the Home Office before finally becoming, in his own estimation, “the most successful Chancellor of the Exchequer since 1945”.

Throughout his service as Margaret Thatcher’s tea trolley, he professes amazement that someone with his views was consistently given advancement by someone with hers. But Clarke’s characterisation of Alan Greenspan, the Ayn Rand-worshipping precipitator of the global financial crisis, as “one of the wisest men I had ever known” indicates that his self-proclaimed one-nation instincts hardly go very deep. Nor did his readiness in 1997 to run for the leadership of his party in a pact with John Redwood suggest that his differences of outlook with the swivel-eyed were as principled or profound as he pretends.

In Clarke’s observations about colleagues, it's impossible to disentangle failures of curiosity from failures of style

To every job he was given by Thatcher, he brought the same prejudice and applied the same tool kit. Like his boss, he never met a trade union he didn’t dislike. So any objection that a professional group – be it prison employees, nurses, teachers, rail workers, miners or, particularly, doctors – brought to any detail of any Conservative plan for privatisation or reform was automatically dismissed as the pleading of the pampered. A laughably inadequate account of the miners’ strike, in which Clarke takes up the blase pose of not understanding why people want to be miners in the first place, presents the conflict purely as a strategic test of strength for the government, and without any sensitivity to the fact that it was, both culturally and industrially, the most resonant domestic disaster of the period.

“I am,” Clarke says, “the least observant of men.” He refuses at any point to extend sympathy to workers who need to organise in order to maintain their living standards, but he chooses, meanwhile, to insert a whingeing paragraph about how heartbreaking it was for parliamentary undersecretaries in 1979 to struggle along on a salary which is, in today’s money, £49,400 a year. When it comes to lavishly subsidised cartels, he is a bluff and outspoken critic of everyone’s except his own.

Clarke’s observations about his colleagues are so lame that it becomes impossible to disentangle failures of curiosity and failures of style. From the moment John Profumo is dubbed a “charming and delightful man”, the reader must sharpen their scythe to hack through a dense thicket of transcribed cliche. The word “congenial” is beaten into the ground, repeatedly deployed to describe any fellow politician whom Clarke likes but can’t be bothered to portray.

Thatcher, you will be surprised to learn, “constantly argued with her colleagues, sometimes being unpleasant and even rude”. Clarke’s own relationship with “the best prime minister I ever worked with” was “robust”. Tony Blair was “highly intelligent”. Willie Whitelaw, on the other hand, “was not intellectually brilliant, but nor was he stupid”. When Britain crashes out of the ERM in 1992, a long and pointless defence of the useless Norman Lamont is mounted, as though it were somehow not the chancellor’s own fault that his “completely discredited” government had “its economic middle stump flying through the air”. Lamont’s refusal to resign immediately is excused on the incontestable grounds that he was Clarke’s personal friend.

A rare point of thoughtfulness comes when he regrets that his wife was far more upset by public criticism of him than he was himself. When a comedian says on the radio that among the few things making life worthwhile are “birdsong in the spring … and the prospect of seeing Kenneth Clarke going to his grave”, it is Gillian who rings the BBC to complain. But at no point does Clarke de-monologue to ask himself whether the impact of his policies might have justified those attacks, which he complains were invariably “savage”, “synthetic” and “unfair”. A similarly promising passage arising from when, as home secretary, he had bravely started to address the scandal of rising prison numbers is quickly cut short when Michael Howard takes over the post. A typical Clarkean coda adds that, in spite of Howard’s law-and-order populism destroying all hope of progress, the two of them “as ever, remained friends”. Club before country, as they say in Westminster.

Clarke’s life in politics has been bookended by the decisions to join and then to leave the European Union. A hurried epilogue on Brexit is clumsy and shallow. Politics, he says at one point, is nothing if not a test of stamina. But it’s also a test of self-knowledge. That’s why Kind of Blue is kind of boring.

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