It's the job he always wanted, and it seems John Hutton wants everyone to know he’s arrived. Striding across the packed forecourt of Euston station in London, the new secretary of state for defence swings his ministerial red box so conspicuously that even the doziest commuters must realise someone important is around.

Unlike other cabinet ministers, Hutton is allowed to carry the telltale briefcase in public, because he is surrounded by security staff.

From relative obscurity, he now has one of the weightiest jobs in cabinet – and with it becomes a top terror target.

Fewer than 18 months ago, Hutton’s career hung in the balance as his old ally Tony Blair prepared to leave Downing Street. When he was accused of declaring that Gordon Brown would be a “f***ing disaster” as prime minister, his fate seemed sealed.

However, the new leader kept him on as business secretary – a symbol of his commitment to a government “of all the talents” – and in the recent reshuffle gave him his dream job.

He’s just back from his first tour of Afghanistan and Iraq and is determined to convince a weary and sceptical public that these wars are a good thing.

“It’s an incredible operation. If people back home could just see it, they would be so proud of what we’re doing there,” he enthuses.

However much Hutton, who has published one military history book and is working on another, wanted this role, he’s painfully aware of the challenges. Many people don’t understand, or have forgotten, why Britain is on these expensive and long-drawn-out missions in Afghanistan and Iraq, he admits.

“It’s first and foremost about UK national security,” he says. “ If Afghanistan or Iraq becomes a state where terrorists can roam freely, that terror will be exported to our own doorsteps.” There is “no option” but to succeed, he says.

While he is confident of success in Iraq, and predicts a big pullout of UK forces in months, his assessment of the situation in Afghanistan is bleak.

“The problems are fundamental – 30 years of civil war, a succession of failed states, Islamic extremism and permanent insurrection, overlaid with narcotics crime and drug warlords – it’s impossible to imagine a more poisonous cocktail than that,” he says.

This month Britain’s top commander in Afghanistan, Brigadier Mark Carleton-Smith, warned that the war against the Taliban could not be won. He talked of reducing it to a “manageable level of insurgency”.

Hutton is not as gloomy, insisting it will be possible to crush the Taliban forces. However, he believes this is a long way off – and warns that the situation is so unstable at present that devoting resources to reconstruction is misguided.

“You’ve got to deal with the insurgency first and foremost. Unless there’s security, not just in Kabul but the rest of the country, you can put in all the social investment and economic development you like – it’s not going to work. If the Taliban turn up a month later and bulldoze the school you’ve built, then you’re back to square one.”

How long will British troops be there? “I think we have to realise we’re in for the long haul,” he says, without putting a figure on it. Pushed, he predicts it will be “years” before the Taliban are crushed, and “could well be” decades before our other objectives are achieved.

If more troops are needed, he makes it clear he wants Nato allies to supply them. “We are pulling more than our weight,” he says. “There has got to be fair and appropriate sharing of the burden across Nato countries.”

His reluctance to commit more resources to the operation is understandable, given how desperately stretched the military is. Hutton is surprisingly frank about the shortage of money, making it clear he plans to axe one or more big procurement projects.

“We’ve got to make ends meet,” he says. He admits this means “some changes on the procurement side”.

He won’t be drawn on detail, but insiders believe his comments spell the end of the £9 billion joint strike fighter (JSF) jump-jet project. Plans for 25 transport aircraft for the RAF are also likely to be at risk. Some other big projects, however, such as the Eurofighter and the Astute submarine, are just too costly – both politically and financially – to abandon at this stage.

“There’s precious little point in cancelling a contract if it ends up costing more as a result. I’d rather have the kit than the liability,” Hutton says.

He insists the military can cope with its commitments, but admits it is under “a lot of pressure”. “There’s not always been the opportunity to maintain the distance between operational tours that we would like. It’s not how it should be,” he admits – meaning they are not getting enough rest between battles.

In spite of all this, he is adamant that morale in the military is “extraordinarily high”. He believes military parades are a “brilliant way” of boosting it. “The public loves to see guys on parade. I would like to see more,” he says.

What about bystanders who jeer? “Those kind of cretins are going to be out and about but they don’t represent the public,” he says scornfully. “We shouldn’t be afraid to take those people on.”

He’s also keen on the idea of a European army, as long as it doesn’t stretch our resources even further. It would be sent to international trouble spots.

“I think we’ve got to be pragmatic about those things. I think that’s perfectly sensible. France is one of our closest allies, and the French believe very strongly in this type of role. If we can support it, we should.”

By now the train is pulling into his constituency, Barrow-in-Furness. It’s where sections of two huge aircraft carriers are to be built. That project, at least, seems sure to be safe.

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