Mo Mowlam will go down in history for two things. She was Secretary of State for Northern Ireland when the Good Friday Agreement, that benighted province’s best chance for peace, was signed, and probably had much to do with persuading the Republicans to engage in serious negotiation. That did not endear her to the Unionist side, who lobbied hard to have her removed, ultimately successfully. And she has weathered a brain tumour that left her exhausted, six stone heavier, and bald, while still carrying a full ministerial workload. She said nothing about it until a cruel woman journalist wrote that she resembled a Geordie trucker. Mowlam asked for no sympathy, merely remarking that she was rather fond of Geordie truckers.

Mowlam’s courage and character are not in doubt. Her popularity with the public was secured as the Ulster tragedy seemed, jerkily, to come to an end under her guidance. She was the epitome of New Labour: classless, able, hard-working, energetic, sincere, concerned about the welfare of all about her, famously iconoclastic and endearingly modern. She sent her police protection officers out to buy tampons. She cuddled up to Unionists who probably have trouble kissing their wives. She would kick off her shoes, put her feet up (sometimes on the table) and offer everyone a cigarette. She spoke movingly on television about life with an alcoholic father. The effect she had on new acquaintances caused them repeatedly to describe her as ‘stunning’.

The picture that emerges from Julia Langdon’s biography is a little different. Two of Mowlam’s staff in Redcar took her to an industrial tribunal to obtain a ruling that, by cutting their wages arbitrarily, she had broken the law. In a love life even Mo herself has described as spectacularly chaotic, there have been no children and no marriage until recently. Several of her boyfriends were married to someone else. At least one abandoned his wife and children for her, before drifting off to another woman.

Her office was as incompetently run as her private life, the staff finding it hard to cope with four hundred constituency cases a year – I wonder how they would have managed in the much larger seat of South Derbyshire, where our caseload was regularly over a thousand. And she has a tendency to grab credit where maybe it is not quite due. I was not aware, for example, that Mowlam was a leading light in the campaign for homosexual equality in 1994. The Labour MP who proposed the key amendment with me was not Mowlam but Neil Kinnock.

Now I am sorry if this sounds a bit sour. Mo is a remarkable person who deserves a full-length biography. Langdon clearly adores her subject; a less adulatory and more objective tone would have been welcome. For while Mowlam has her share of admirers, especially amongst the public, political colleagues have often viewed her with a more jaundiced eye. Gordon Brown once asked, à propos of Mowlam’s political views, exactly what she was for. Both Brown and Peter Mandelson have been actively hostile and campaigned for her demise. It is worth asking why these consummate political operators apparently disliked and distrusted her, if her sterling qualities were truly so dominant.

Misogyny has played its part. Despite her three years’ hard slog in Barnsley, local Old Labourites were not going to award a key seat to a female, and especially not a youngish, attractive, unattached bird like Mowlam. She was extremely lucky that the Redcar seat fell into her lap in 1987: that tale as told by Langdon is deliciously entertaining. Nor was her arrival in the House of Commons quite as glorious as Langdon seems to think; I don’t remember Mowlam as stunning, but as tatty and scatty. Janet Anderson, Harriet Harman, Alice Mahon and Audrey Wise were all more impressive on a range of subjects, including the ‘women’s issues’ Mowlam disdained. She was more likely to be found in Annie’s Bar downing pints, chatting up the fellahs and pretending to be one of them, not one of us.

I would have liked to praise this biography. It is an enjoyable read. But it’s thin, ultimately not a thoughtful review of recent British politics by a seasoned observer but a book about one woman by another. In years to come, Mowlam will be seen as a brave lady done down by men. That’s only part of the story. Perhaps in her own version, due after she leaves politics, we will get something closer to the truth.