Geoff Hoon is known to experience the odd pang of nostalgia for “the camaraderie of the robing room” where, as a provincial lawyer in a supportive fraternity, prangs and clangers were no cause for recrimination.

Instead, as a besieged defence secretary, he faces a swelling chorus for his resignation. He is now reproached by the voice of a dead soldier who complained in an audio diary about equipment shortages before he was shot dead in Iraq for lack of body armour.

It is Hoon’s great achievement that after elevating blandness to a level that earned him the nickname “Geoff Who?”, he has transformed himself into the shooting gallery duck that everybody is gunning for. If sympathisers for the late Sergeant Steve Roberts don’t get him for his legalistic evasions and inability to apologise, Lord Hutton almost certainly will, goes the refrain.

The 50-year-old MP has collected quite a few sobriquets. The tabloids dubbed him “Hoon the Goon” and even “Buff-Hoon”. When his star was in the ascendant, Robin Cook was heard to wonder: “How high the Hoon?” But now it’s “High Noon for Hoon”.

He is everyone’s favourite fall guy in the Dr David Kelly scandal. Hoon’s duty of care to the government weapons inspector who committed suicide is a key issue in the Hutton inquiry. Some politicians thought it significant that last week Tony Blair declined to express full confidence in his defence secretary.

Hoon presents a pitiful and slightly comic figure. With few friends in the media, excluded from Labour’s charmed circle, he has been something of a plaything for Blair. Having allowed Hoon to believe he might be reshuffled to the Department of Trade and Industry, the prime minister kept him in place as a lightning conductor for Hutton.

Back in September Hoon proclaimed at the TUC conference in Brighton that he would not quit and that Hutton would absolve him. Privately, he is now said to expect flak from Hutton and if he takes a direct hit he is willing to contemplate the inevitable.

Who is Hoon? Outwardly affable, lawyerly and unperturbed, what other traits are masked by his impassive public face? He is certainly lucky — or skilful — at dodging incoming fire. He has survived an unusually long four-year tenure despite sending more British troops to battle than any defence secretary since the second world war.

Paradoxically, as Hoon’s conflicts became incrementally larger, scaling up from Sierra Leone to Iraq, Britain’s overstretched forces became smaller. Within a year, we are told, the Royal Navy will be outnumbered by its French equivalent for the first time in 300 years.

Yet Hoon has received only one public rebuke from a serving brass hat, when Admiral Sir Michael Boyce, then chief of the defence staff, suggested the government’s handling of the firemen’s dispute might compromise British forces awaiting action in Iraq.

It is not as if Hoon had avoided giving hostages to fortune. His insensitivity has never been a serious impediment. When 40,000 service personnel had their leave cancelled before the invasion of Iraq, Hoon went on a family skiing holiday in Chamonix. During Kelly’s funeral Hoon was on a summer holiday in America, declaring that his wife Elaine had threatened to divorce him if he did not accompany her and their three children.

There have been several notable failures of lip-synch between Hoon and other branches of government. His contention that the Ministry of Defence did everything possible to protect Kelly’s anonymity was at odds with evidence that the MoD effectively leaked the scientist’s name. When Hoon professed innocence of any such policy he was apparently contradicted by his own special adviser, Richard Taylor.

His admirers insist that another Hoon persona exists — a laughing, convivial, delightful wine connoisseur who is kept from the public gaze. “His low-key image is deliberate, because it is a department where you don’t play politics,” says one. “Over dinner he’s a different bloke, animated and funny. And his political skills are pretty finely honed.”