It used to be said of Gordon Brown that he would identify where Tony Blair stood on any particular issue and place himself one step to the left. The same could be said of Peter Hain, except that he would take two steps. This is the ideological and political ground on which the battle for Blair's succession is taking place. The closer that day beckons, the more discreet and gentlemanly the protagonists seek to become. As Leader of the House of Commons after years of being the nearly-man of the cabinet, Hain is now in a pivotal position. He is fastidiously loyal, while giving the impression that with each sentence he is marking out his own ground. Expect more of the same at the party conference in Bournemouth.
Hain has form. He is scarred by an incident in June when he floated the idea of the rich paying more tax to enable middle and lower earners to pay less. Nothing particularly outrageous about that, but these are sensitive times for a sensitive government. The "Tax the Rich" headline in the Daily Mirror didn't help, but Hain was not prepared for what he calls the "ballistic" response the next morning. That was followed by a terse one-liner from his friends at the Treasury: "It is the Chancellor who makes decisions on taxation in budgets."
Hain mentions the episode himself. We are talking about the themes of the moment - trust and disillusionment. "There's a crisis of the political class." He defines that as "Westminster journalists plus government and opposition politicians. We are conducting the political debate in a dumbed-down fashion. More and more people say to me, it's not a question of whether the government is right or wrong, it's a question of wanting an intelligent take on the big issues, and people are not getting that."
The conclusion he drew from the tax furore was: "You can't say anything." "You can't say what?" I ask. "You can't say interesting things, however modest and however tentative and however common-sense." He points to the contradiction at the heart of the media-political relationship. "There is a desire for government ministers to say interesting things in a less uptight fashion. But if you do that, you risk getting blown out of the water. I don't mind. I'm adult. I've been around a long time. I can take the knocks. I just think it's a shame for British politics."
His analysis would be broadly accepted on both sides of the media-politician divide. But this veteran of many a political battle since his days of threatening to rip up cricket pitches in the late 1960s is no naIf. One reason the Chancellor was so cross was that he detected a sortie into his territory from a man seen by some figures around Blair as their new favourite.
Like Brown, Hain positioned himself on the war as staunchly loyal. He was an ardent advocate of regime change in Iraq, and remains so, trying to argue the case from a leftist perspective. But his justifications, while still passionate, are now just a little qualified. "I still feel we were right to do what we did." It would have been better to secure a second UN resolution, but this, he believes, would not have changed the situation on the ground. "This was about least-worst solutions." And what of those elusive weapons of mass destruction? "I was not in the war cabinet and not taking key decisions, but I always thought that Tony Blair made a very convincing case in the circumstances - given the intelligence that I saw." He adds: "I haven't seen any intelligence officer say we were wrong to pass this information to ministers."
Had someone embellished, made things up, somewhere down the line? If not the UK intelligence services or the Americans, then the people on the ground who fed them information? Were ministers sold a pup? "I really don't think so. But all I can say is what I saw coming across my desk." That is not the most categorical denial. Wiggle room for the future? But Hain adds that on WMDS he has "no reason to doubt that things will be recovered".
Hain says he understands and respects the position of opponents of the war, among them many friends, his family and members of his constituency party in Neath. "You can legitimately ask penetrating questions like these. They're fair and I don't quarrel with them, but associated with that line of critique is amnesia about what Saddam Hussein's regime was like. In the great balance of judgement on the moral issues, I want a world where Saddam is not in charge of the world's most brutal tyranny of modern times. Iraqis have been liberated from his evil tyranny."
This he calls "progressive internationalism", of which "liberal intervention" - waging war against tyrants wherever they may be - is a subsection. This world-view contains the fight against global poverty, for fairer trade, human rights through multilateral institutions such as the International Criminal Court, a comprehensive test ban treaty, the biological weapons convention, Kyoto - in short, as Hain concedes, everything that the Americans are opposed to. "You don't have to agree with coalition partners on everything they stand for."
Hain cites the Blair mantra of "tough choices". But what happens when the next choice comes around, assuming the US neo-conservatives still have the appetite for another "pre-emptive" excursion? Hain is categorical. "I don't know anybody serious in government who thinks that we can replicate Syria or Iran or North Korea with what happened in Iraq." There is a confusion, however. Britain, he says, must not "duck our responsibilities" to protect human rights by force if necessary, but at the same time he suggests that Blair should be somewhat wary of the voices whispering into the ear of George W Bush. "If some of the wilder exponents, some of the extremists, were to be curbed in terms of their axis-of-evil type of fantasies, that would be a good thing."
On Europe, Hain sought at the start of the year to recalibrate his position more towards the Treasury's, but nobody noticed. So he tries again. "I've never ever been fanatically pro-euro, like some are at any cost." He puts Charles Kennedy and Kenneth Clarke in that camp, but none of his cabinet colleagues. "I've always thought we have to judge it very rigorously according to the economic circumstances." Brown would say amen to that. Given that almost nobody believes there will be a positive assessment when the Chancellor looks at it again in the Budget next spring, what chance is there for any movement before the next general election? "I've never felt you should put an artificial timeline on it." This is a new, euro-cautious Hain.
W e turn to domestic issues. What does the Labour government stand for? Hain gives me a shopping list: "Social justice, freedom, equality, redistribution to ensure that those at the bottom are lifted off the bottom, and redistributing power." By the last point, he means devolution and the decentralisation of public services. "We have made significant strides along that road. I don't think we've been very good at explaining what we are doing."
He insists that the government has been much more radical than it has been given credit for. I suggest that this might be political and intellectual timidity on the part of the boss, to which he replies: "The brilliance of Blairism is to introduce radical change without frightening the horses."
He adds: "From the point of view of someone on the left, I understand the point you're making: that this hasn't been put up flashing in lights. But the changes have been introduced. The problem is that if people accept that change, and pocket it without attributing it to us because we haven't proselytised, then we end up being seen more negatively than we deserve."
The lessons were, he suggests, plain to see in the Brent East by-election. Strategically Labour has failed to get its message across, and tactically it failed to take on the Liberal Democrats. Hain says that the Lib Dems could prove fatal to Labour in scores of marginal seats by providing a "comfy option" for its disgruntled voters. "Charles Kennedy is moving them out of an overtly progressive alternative to Labour on the left to reoccupy the centre right. That poses a huge threat to the Conservatives, but also to us."
As we sit in his grand Privy Council office in what was once Lord Kitchener's home, I marvel at the sight of Hain talking of a big ideological battle ahead and of Britain remaining a conservative culture. "I notice all around me the establishment, which was quite happy to tolerate us in the first term because the Tories were a total mess and we provided a relatively safe alternative, now really resenting us. You can feel that coming at you from all directions." Sometimes, just sometimes, he likes to give that old language an airing.
So what next? With Alan Milburn and his like gone, is Hain really Downing Street's newly anointed "stop Gordon" candidate? He laughs. "I think this is a joke. I've been in the cabinet not even a year. A year ago, Charles Clarke was being spoken of in these terms. It's a fashion thing - no more or less than that."
He says his memories of Brown go back to 1970. "Gordon was the 'stop the tour' organiser. I worked with him then. I've always had a very high admiration for him. He's one of the most formidable brains in modern politics and hugely impressive intellectually." Hain concedes defeat in the economic arguments they had ten years ago. "He was clearly right on those. He usually thinks five steps ahead. You just look at the way he's run the economy. It's very difficult to fault."
Generous to a fault, you might say.