In Manchester this week Gordon Brown attempted to define himself as the man best equipped to lead the Labour Party into the next general election. But for many in the party and the country, his faults have been found out, and there is no going back

Of course nothing has changed. It was never going to. Gordon Brown made a decent speech which pleased his immediate audience and disappointed those who believed it might mark any sort of tipping point in his career as Labour Party leader and Prime Minister. At the beginning of the week in Manchester it was evident that the party leadership was in desperate trouble, that the party's fortunes were almost certainly irrecoverable this side of the next general election - whenever that might be - and that it was utterly impossible to predict what might happen next or the circumstances in which Labour might seek to resolve its electoral prospects. That remains the case.

T.S. Eliot is often pressed into use in relation to Gordon Brown, previously because of the rather tired Macavity-like comparison, something which has ceased to be so interesting since, as Prime Minister, Mr Brown has inevitably been obliged to be "there" and take the rap - which is, of course, why he is in the unfortunate position he now finds himself. The much more relevant Eliot reference today is perhaps that provided by the Fourth Tempter in Murder in the Cathedral who appears unexpectedly to speak to Becket (who anticipated only three temptations as he contemplates death) and obliges him to consider the deadly sin of pride. "You know and do not know", says the Tempter, "what it is to act or suffer ... That the pattern may subsist, that the wheel may turn and still / Be forever still."

For this is Gordon Brown's dilemma now. It doesn't really matter what he said in Manchester on Tuesday - not, at least, as long as he made a half-decent fist of it, as he did. The wheel has turned, but it doesn't make any difference. The public, as well as the Labour Party membership, knows and understands that here is a dedicated and sincere politician who is apparently seeking to make the world a better place: computers for kids, cancer care, free check-ups, nurseries for the tots and dignity for the deserving elderly - these are all welcome sweeties, but none of them matters a jot to the political future of Gordon Brown. No figure of additional matrons in the NHS, however noble and bold, is going to do anything to make Gordon better, at least in the eyes of the electorate.

It is over for him. The contents of his speech, the style of his delivery, the reception of it, are all nothing more than buoys that the Prime Minister is floating past on an ill-fated voyage to political oblivion. The opinion polls tell the same story and they have been doing so for many months. The only uncertainty now involves timing. Nothing that happened in Manchester affected anything. Only the rocks beckon.

It is one of the elementary rules of political life that any over-anticipated event is bound to fail to match expectations. Such is always the case in the House of Commons, but it is doubly true at party conferences because there are two refracting mirrors here which both greatly distort the picture they reflect: the loyalty of the party members present is one and the excessive excitement of those in my trade is the other. There have been a great many of us in Manchester, corralled together in heated pursuit of only one story. It was always going to end up a disappointment for the news desks.

So now poor Gordon Brown, having waited so long for a position and a power he so desired - and, most importantly, having failed to grasp or, at least, stand for the party leadership against Tony Blair in 1994 - finds like Becket that everything has arrived 30 years too late. "Ambition comes when early force is spent/And when we find no longer all things possible. / Ambition comes behind and unobservable."

This time almost exactly a year ago, a discerning former government minister defined the problem, in the immediate aftermath of Mr Brown's decision not to hold a general election (which was another palpable failure of his to use power to take power) in terms of the priority for the Labour Party.

"We all think, whether or not we are in office, that what matters is for Labour to win the next election, whenever that may be. It doesn't matter who the leader is. It is winning that matters. If Gordon Brown can win, that's fine. If he can't, we need to look for someone else."

And that is how the party still sees it now. Yet 12 months on, while the vulnerability of the party's existing leader has become only too evident, the identity of that "someone else" is still unclear.

Jack Straw as an interim stand-in leader to take the flak and lose the next election? It could hold some otherwise lost seats. Or what about David Miliband? He is for many people at Westminster the obvious, intelligent alternative future leader. He has spent the last few days seeking to play his part constructively as a loyal member of the Government without appearing to advance his own interests at the expense of the collective ones of the party. This hasn't been easy and he is right to try to avoid "a Heseltine moment", but this is the second time he has taken such evasive action. When he decided not to stand against Gordon Brown in a leadership election last year - as I understand it on the advice of Tony Blair's former adviser Anji Hunter, who counselled that "your time will come" - he chickened out. The day after that decision, at a private dinner, it was clear that he already suspected that he might have made a mistake. It's make-your-mind-up time now.

Just like it is for Gordon. He wouldn't have won if he had stood against Tony Blair in 1994, but he would have been true to himself. That is what we were told his speech at Manchester was going to be about and yes, perhaps it was. But he should have been true to himself and his ambitions all those years ago in 1994. The truth is that he is a man who calculates everything so carefully that it has proved extraordinarily difficult for him ever to be himself. That is something that the public instinctively comprehends, so much the worse for him.

Becket's dilemma, the last temptation, the greatest treason, was this struggle with pride, whether to do the right thing for the wrong reason; the suggestion that however noble the cause, it has no value unless one's motives are pure. That is where Gordon Brown has been found out and it's far too late now for him to do anything about it.