John Reid is being nice. At least two national newspaper editors came away from dining with him during the Labour Party conference full of surprise at his charm, his interest and his cleverness. For those who know him mainly for his aggression on the Today programme, or for the Glasgow knucklehead twitch of his shoulders on television, the softer side of the Secretary of State for Health can come as a revelation.
But it is not just ambition that explains his prominence as a persuader for a Prime Minister whose pitch for the centre ground often seems to take him too far to the right. Reid has always been one of New Labour's outstanding ideologues. Now, he is one of its most compelling advocates of the unpopular alliance with the re-elected George Bush. When I explained to one of his friends that I wanted to talk to him about whether there was such a thing as Blairism, that would endure after Blair had gone, I was told: "John was Blairism before Blair."
Which is true. Ever since he lost the Marxist faith of his youth, Reid has been a rigorous revisionist. His core message is simple: the ends are the same, the means are ever-changing. It was the message that drew him to Neil Kinnock's attention, launching his political career in 1983. And it is the same message he preaches now.
But what lifted him to the Cabinet has been his persuasive skill. His style in person may be a little brutal for modern media tastes, but the clarity of his ideas and his knack of vivid expression have rendered him invaluable to two Labour leaders. As a speechwriter for Kinnock, he provided the arguments and the language to start to drag Labour away from Bennite fundamentalism towards a compromise with the electorate.
He gave Kinnock the "enabling state", a phrase and concept running through his own political career and the recent history of the Labour Party like steel thread. The same skills of ideology and language were on display when he took over at the Department of Health last year, after Alan Milburn retreated, bruised, from a struggle with the Treasury over foundation hospitals. One admiring policy adviser in Downing Street predicted that, within a year, Reid would claim that foundation hospitals were the brainchild of Keir Hardie, the founder of the Labour Party. Within two weeks, Reid was claiming that foundation hospitals realised the true vision of Aneurin Bevan, an even more potent left-wing pin-up.
It is certainly true that Reid is good at selling the market-style reforms of the health service, both to the Labour Party and to the general public. He avoids the word "market", using instead "the power of preference". He is working, too, to soften his reputation for personal abrasiveness. When I saw him in his Department of Health office, he launched unprompted into a mea culpa. "I'm just me and I find difficulty in changing me, even for those who think I should have a less passionate image. If you believe in politics to the extent that you want to commit your life to it, there has to be a degree of passion to it. And I accept that, on occasions, that means I'm not as smoothly spun as some other politicians."
And he has committed his life to politics. The son of a postman, he left school in Coatbridge, on the outskirts of Glasgow, to work as a labourer and insurance rep. Politicised by the poverty he saw on his patch - the tenements of the East End of Glasgow - he joined the Labour Party.
Then his girlfriend Cathie (they married in 1969) bought him The Rise and Fall of the Third Reich by William Shirer, which he read on a long train journey. He was "spellbound", did an Open University course and went to Stirling University at the age of 25. He joined the Communist Party and became a student politician as the vice-chair of the National Union of Students in Scotland. His PhD began as a Marxist analysis of the slave trade in 19th-century Dahomey, but he was soon disillusioned with Communism as a guide to practical action. "I used to believe in Santa Claus," he says of that period of his life. But it left him with a distinctive style of thought and diction. No other cabinet minister is in the habit of quoting Gramsci and Eduard Bernstein, or refers in passing to living in "an age of advanced capitalism".
After rejoining Labour and working in Kinnock's office, he became an MP in 1987 and, although he was not promoted to the Cabinet until 1999, he has held five cabinet posts in the past five years: Scotland, Northern Ireland, Labour chairman, Leader of the House and Health. His job turnover is a testament to his value to Blair as an ambulance-chaser of political crises.
Despite his domestic policy responsibilities, his biography gives him a special authority to sell the Iraq war message to those sceptical of America's motives. In 1985, he travelled with Kinnock through the United States to meet the Sandinista leadership in Nicaragua. Because of his Communist past, he was confined to "airports only" by his visa, putting him in roughly the same category as Yusuf Islam - the former pop singer Cat Stevens - who was recently turned round at a US airport and sent back to Britain. "Neil was met by two officials there and I was met by four," Reid says.
He argues that US policy has changed now. "I spent many years of my life arguing bitterly against the Americans, in places like Chile, bringing down democratic regimes and putting in frankly fascist regimes. Why on earth would I not celebrate when they bring down a fascist regime and bring about a democratic regime?" Reid says: "People say to me, 'How can you support George Bush?' My view is that if the Americans reach a decision which I have reached independently as being the right decision for this country and the Western world, I am not going to change my mind because they have reached it."
Reid opposed the Americans when they supported Islamic extremism in Afghanistan against the Soviets. "I said this was a short-sighted policy, this was crazy. Why would I not now say they are right when they have changed? I have been consistent in my value. The problem is that there is a latent anti-Americanism that doesn't ask, 'Are they now taking the right position?' It asks the question, 'Are they still Americans?'"
He tries to explain why, when it comes to combating international terrorism (no "war on terror" for him), he claims to "have the same objectives as many readers of The Independent, though we would disagree over the balance of the means". He begins by asking: "What is the role of a social-democratic government in the post-Cold War world? My own view is: just as we ask citizens at home to accept a balance of rights and responsibilities, so as a citizen of the world, Britain has a role to play in defending our rights and values and at the same time discharging our responsibilities."
It is what one of his allies, perhaps unhelpfully, calls a "Neo-Labour" approach; a left-wing version of the American neoconservative doctrine of spreading democracy and human rights by force, which is regarded with such suspicion by The Independent and most of the British left. Tony Blair said last week that "if you put it in a different language", the neoconservative agenda "is a progressive agenda". Reid is noticeably better than Jack Straw, the Foreign Secretary, at doing the translation. He stresses the need to extend the "hand of friendship" as well as responding to terrorism with the "iron fist". He speaks of encouraging Turkey to enter the European Union; of Straw's role in helping Pakistan and India back from the nuclear brink; and of continuing to press for political solutions to the Israeli-Palestinian conflict.
Only then does he turn to "this question of Iraq". He does not dwell on the case for the invasion, except to make a characteristically sharp attack on Charles Kennedy. "The question that one has to ask the Liberals is; if it was right on exactly the same legal grounds to take military action in 1998, why is it wrong now?" I am drawn into defending Kennedy. Surely Operation Desert Fox - which Kennedy's predecessor Paddy Ashdown supported - was different, because it was a limited aerial bombing campaign? He counters before I have finished the sentence: "They think it was a smaller illegality they supported, was it, because it was attacking from the air, and now it's a larger illegality?"
Almost as swiftly, he moves on beyond the original decision to intervene. The question is now, he says: "Do you think we should just get out and leave it to the Iraqis? Or do you think it is in the long-term interest of Iraq, world stability and ourselves, as well as Islam, to stay and to allow the Iraqis to tell us when to go?" It is a view that had some support among Labour delegates at the party conference in Brighton. Some told me that they had been strongly opposed to the invasion, but that, having started it, Britain had an obligation to "finish the job".
Reid's backing for Blair on Iraq is just part of his larger ambition to promote a "permanent revisionism" (Eduard Bernstein's phrase of a century ago), a constant striving to find new ways to put left-wing values into practice. His tenure at the Department of Health is central to that, because there is a mood in parts of the Labour Party, and in parts of the electorate, that, having done New Labour, the Government can now safely go back to a bit of the Old.
"The more difficult thing for everyone to accept is that renewal doesn't stop," Reid says. "Therefore New Labour is not an event that occurred in about 1994 when Tony Blair is elected leader, Peter Mandelson devises a new party political broadcast strategy, and we change the party constitution. It is a constant process of renewal, otherwise we will fall back into the hole that we dig beneath ourselves."
In the public services, that means pressing on with reforms "to build them around the convenience of the individual, not the producer". That is difficult for some of your colleagues, I say. "It has always astounded me how difficult it is. I've never quite understood why ordinary working people - putting them in charge of the health service - why that is regarded as anything other than the progressive thing to do."
He reels off the changes that are transforming the NHS, always admitting (because he speaks in sub-clauses within sub-clauses) that with change on a scale that has never been attempted anywhere in the world, "not everything will go smoothly". The policies are illustrated with references to the experience of real people, "a single mum with two or three kids, eleven o'clock at night, and a kid develops a cough".
He is reluctant to use himself as a case study. "I don't pretend to be a model for anyone on anything." But he is. Unlike Stephen Byers, the Transport Secretary who could not drive, Reid is a walking advertisement for his department's policies. A heavy drinker, he gave up completely 10 years ago, when John Smith told him to choose between alcohol and a front-bench career. A heavy smoker, he gave up two years ago, after he married the Brazilian film-maker Carine Adler. (Cathie, his wife of 29 years, died of a heart attack in 1998.) "I was starting a new phase of life with a new partner. I recognised that that period would be a hell of a lot shorter if I didn't kick the habit." And he goes to the gym when he can.
Now 57, Reid is enjoying what his friends call a second lease of life. Ambition burns as brightly in him as ever. He has the dubious privilege of being the current holder of the pass-the-parcel marked "SGC" - the Stop Gordon Candidate, the one to whom the Chancellor's opponents would probably turn if the Prime Minister were to depart suddenly. A more realistic aspiration might be the Foreign Office, for which his eight years as shadow defence spokesman and two years as George Robertson's number two at Defence are some preparation.
His detractors say that whatever his PhD was in, it wasn't self-doubt, and there may be something of the working-class intellectual about him that betrays an insecurity behind his sense of his own importance. But he has the priceless political gift that Tony Blair once had, and is now losing fast, of being able to persuade almost anyone that what he is doing is the fulfilment of whatever his audience believed all along.