Labour activists sit on their hands

''People are either desperately worried or incredibly angry." That assessment of his local Labour Party comes from a cabinet minister loyal to Tony Blair and supportive of a war. "If any of us were in any doubt about where the public stands, the march removed that."

Then there was this view from a Midlands council leader I met recently. "It's taken as read in my local party that you're against the war. The only time there's any edge is if anyone stands up and tries to defend it." This man, too, is no rebel.

Hans Blix's report to the UN, the cracks in Nato and the EU, the global demonstrations, have all knocked Downing Street's strategy off course. When Blair tried, in his press conference on 18 February, to wrest back the moral high ground, with talk of human rights and the Middle East peace process, he didn't dispute the mood of the country. He will have seen the polls, the public ones and his private ones. He will have been told of the Second World War veteran, medals on his chest, telling the TV news how he was driven to demonstrate against a British government for the first time in his life.

But how will this translate into action? There are several myths. The first is of a bonfire of party cards. Membership continues to drop steadily, but not a single MP I have spoken to in recent days can confirm mass resignations in his or her constituency. Many Labour members have written e-mails or left messages at their local parties saying that they are considering their positions. But, for the moment, they are hanging in there. One former minister described the mood in his constituency. "My activists say to me: 'What's the point of leaving the party? I'd rather wait until Blair goes.'"

Another assumption is that 100 or so Labour MPs are squaring up for revolt in any debate once military action begins. It will depend on the diplomatic context at the time, but the evidence of six years of the Blair government is that time and again the Parliamentary Labour Party falls into line.

And yet Blair's handling of the conflict is having a corrosive effect on the party, one from which both will struggle to recover. This damage is more gradual and harder to calibrate. It comes from members sitting on their hands. Many MPs are finding it very hard to galvanise their local party to campaign in the local elections. Some MPs don't even bother to ask.

At Old Queen Street, Labour headquarters, they are preparing for a historic low turnout in May, whatever the outcome of the war. The figure they're contemplating is 20 per cent - and that despite far greater use of postal ballots. This would reinforce a sense of public disillusionment with the entire political process, and could lead to a loss of several hundred council seats for Labour. Even without a war, the prospects for Labour in May were bleak, with the national insurance rises announced a year ago by Gordon Brown coming into effect in April. But as ever, the opposition is helping Blair out. Voters angry at the PM's jumping into bed with George W Bush are hardly going to turn to Iain Duncan Smith, acting as ambassador at large for Donald Rumsfeld.

The Lib Dems may do well by default, but satisfaction with Charles Kennedy's decision to address the march was offset by his refusal - even in front of a million or more people - to come off the fence. He has laid himself open to the twin charges of indecision and opportunism. An almost certain beneficiary in pockets of the country will be the British National Party, which is fielding up to four times as many candidates as a year ago, when it won three seats.

So where will this leave Blair? Reports of his demise have been, to paraphrase Mark Twain, greatly exaggerated. The end of Blair would need all the "what ifs" to happen in quick succession: a war without a second resolution; a mass rebellion in the PLP and the party at large; Robin Cook and Clare Short to resign, possibly others; cabinet members to question the PM's judgement publicly; British soldiers to be gunned down by "friendly" American fire; mass civilian deaths; failure to capture or kill Saddam Hussein; an increased instability in the Middle East.

If only some of these happen, Blair will tough it out - though, for the rest of this parliament, he will run a party and a country that is sullen and tetchy. But he and his advisers insist it won't come to anything like that. They believe most of the current malaise is the result of uncertainty. "It's the unknown that is haunting the party," one official says. They believe the war will be over quickly. "I have a good feeling that in a couple of months' time people will wonder what all the fuss was about," one cabinet member told me. I promised I would hold him to his word.