His grandfather was a gunner in the First World War, his father was a Royal Marine in the Second World War, but John Hutton was never a military man. “I grew up in the Swinging Sixties, it was an era of peace and love,” he says. On the train to Barrow, he is reading GQ magazine rather than History Today, he has never polished his boots or had a short back and sides.

He began to be interested when he started representing a constituency with close links to the Army and the defence industry. Last year he published a book about the local battalions that fought on the Western Front. Now the new Defence Secretary thinks that he has the perfect job. He cannot stop talking about “our boys”, making it clear that they are heroes. He has donned the body armour in Afghanistan to see how heavy it is and he loves the ceremony as much as the boys’ toys. “This for me is the best job in government. There’s nothing that compares with it in my experience.”

Mr Hutton, 53, believes that there is a parallel between the troops in the two world wars and the soldiers now risking their lives for Britain. “The current generation can hold their heads high. I have run out of adjectives when I am talking about their bravery.”

Every morning, his first briefing is about casualties. “I still get upset every time I hear that soldiers have been hurt. I write to each family who has lost a child. I think you would be a foolish politician to say you understand the anger that a family can feel. As a parent you have some appreciation of what the loss must be like but it is stupid to guess at the misery.”

This week Gordon Brown announced that British troops would be out of Iraq by July. Does the Defence Secretary believe that the war has finally been won? “I think Iraq is in a fundamentally better place,” he replies carefully. “It is no longer a threat to its people or its neighbours.”

But bombs are still exploding. “It’s a difficult painful journey. People are no longer at risk from Saddamist thugs. But it’s not perfect, it won’t be for some time. It will be a while before there are tourists. There is still a level of insurgency and they [al-Qaeda] are still capable of committing atrocities but they have not prevailed.”

Mr Hutton has never believed that the war in Iraq made Britain more vulnerable to attack. “You can’t combat fanatics with warm words. In the world we live in, you have to take those fanatics on. You cannot hide.” He does concede that the reasons for the war may have changed but he would still have backed the invasion even if he had known there were no weapons of mass destruction. “At the end of the day you couldn’t do business with Saddam. I celebrate the end of one of the most murderous, fascist dictators in the world.”

He sees it as the defining moment of new Labour. “My dad said that the one thing you join Labour for is that it stands up to dictators. That wasn’t just a defining moment of new Labour but a pretty defining moment for the world. I am prepared to accept that maybe the majority thought it wrong, but I believe profoundly it was the right thing to do and I would do it again. The role of the British military has been excellent. We will hold our head up high and have a justified pride in what we have done in Iraq.”

The focus will now shift to Afghanistan. Mr Hutton insists that the mission there is about security on the streets of London as well as safety in Kabul. “The argument is very clear. This is where our national security is determined. We must tackle the threat at source, it’s not just going to go away. It is a struggle against fanatics that may not challenge our borders but challenges our way of life in the same way the Nazis did.”

The military campaign – in which 134 British soldiers have died – has, he admits, been “much tougher” than anyone expected. “The insurgency has been stronger, but I think the deployment now is producing significant results. We have to stay the course. The key thing now is not that the Taleban or al-Qaeda can defeat us in Afghanistan – their tactic is to outlast us. So we need to make political and economic advances as well.”

Barack Obama is planning a surge in Afghanistan next year. If he asks Britain to join it: “We would look at the request very seriously indeed. The US are our principal allies – no one wants to jeopardise that, but the discussion has to be taken with our other allies and there would have to be a debate in Parliament.”

The public should, he says, prepare for a long haul. “We will stay there as long as is necessary to secure all our objectives. It’s going to be years.” This week, Kim Howells, who was until recently the Foreign Office Minister responsible for Afghanistan, said that the country was “corrupt from top to bottom”. Mr Hutton concedes: “There is a lot of corruption in Afghanistan and it’s got to be tackled . . . But there’s a myth about how capable the central Government is in Afghanistan.”

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