Why is PM seeking war on home front?

If Tony Blair fights and wins, he will be unassailable. If he loses next week’s vote, he will have little choice but to resign. If he falls, then his lieutenants - Alan Milburn, Charles Clarke, John Reid - will topple like dominoes.

Most staggeringly, it is Mr Blair who wants to bring this to a head. The Prime Minister is being advised not to hold a vote - but wants to take his case to Parliament and actively seek the decision which could end his career.

These are the stakes and, for the Blairities, this is their most terrifying hour. Of all their battles - the trade union block vote, abolishing Clause IV - none has taken them this close to the edge.

Their talk is not about the United Nations. Hopes of a second resolution have died. The focus is on next week’s debate. For the first time in post-war history, a British government will be asking the Commons’ permission for war before troops are committed.

The question has never been asked before because the answer is so often no. Every MP who troops into the "yes" lobby will have thought of the body bags returning from the Persian Gulf.

Images of one million protesters who marched in London and Glasgow last month will be playing heavily on their minds; and the voters at home, suspicious that Britain is lamely following the United States into a war for oil.

For the scores of back-benchers who have long resented the Blair project, there has never been a better chance to vote down both him and his entire apparatus. War is the one issue where a Labour MP can defy the party leader without the charge of treason. There are several constituencies in the UK where rebelling MPs would be praised for fidelity to the "Labour movement".

There is also safety in numbers. There were 121 Labour MPs defying a three-line whip during the last Iraq vote, committing the ultimate political sin. No party can cast a third of its MPs into the political wilderness.

Finally, there is a coherent ideology uniting such rebels with the historic roots of their party. They believe in the state: public services run from the centre under common ownership.

Mr Blair believes in the market. Tuition fees, foundation hospitals, private finance initiative - a trio of policies designed to empower the producer. It is state socialism versus social democracy.

Here is clear red water - ideological and moral cover for the rebels. There will never be a better time for a Labour MP to get rid of not only Mr Blair but his entire entourage and political credo. The Prime Minister’s response: bring them on, all of them.

For the Cabinet, the next few days will separate those loyal to the Prime Minister and those who have preferred to keep a suspicious silence, half hoping for a seat at the table should he resign. This is the choice being presented to them.

The policy is working. Gordon Brown, Mr Blair’s most obvious successor, made a rare foray to the airwaves in defence of the man with whom he forged New Labour.

"I don’t think there’s been any doubt about my position. I’m 100 per cent supportive of Tony Blair in this," he said last night.

Mr Milburn, the Health Secretary, chose yesterday to publish his hugely controversial foundation hospitals bill, proposing the biggest surrender of state power since the privatisations of the 1980s. It is the manifesto of Blairism - and rebels hate it.

Already, 116 of them have signed a motion opposing it. It means every hospital in England will be set free from state control, then made to compete with private and not-for-profit companies rivals. Mr Milburn chose yesterday to bring it on.

This is a theme. The Prime Minister is choosing conflict over consensus - knowing that, if public service reforms do not go through now, the results will not be available at the next election.

Courage or cowardice; reform or retreat, for Blair or against him. This is the language being used around Downing Street.

Mr Blair has not stopped at Iraq. He is fighting on all fronts - flying to Northern Ireland last week to hammer down the peace process, urging David Blunkett to deliver an antisocial behaviour bill and imploring Gerhard Schrder to reform Germany’s economy.

To take on so many battles looks like rage. But Mr Blair’s strategy runs deeper. Painfully aware of the lack of progress his first term in office represented, this is how he wants it to be from now on.

Margaret Thatcher is the model, in methodology if not in policy. Blairites look back and admire the scope and audaciousness of her reforms - if only Labour’s agenda could be implemented with such speed.

The problem in making Labour work has been akin to the problem with the United Nations. The idea of focus groups and governing by consensus meant moving at the pace of the least willing.

"Thatcher realised that you don’t need a majority. You can get by with 30 per cent or 40 per cent support - and bring with you those who just want leadership, right or wrong," said one Blair aide.

To hell with the majority - let’s do the right thing, and let those who like it join us. It’s the message from the White House over Iraq and the message from Downing Street over public services.

The difference between Thatcher and Blair is that the Iron Lady largely had her party behind her, certainly once the Wets were mopped up.

She was fighting enemies outside her own tribe - the bolder she became, the stronger her position inside the party.

The opposite is true for Mr Blair. "We reject the quiet life," he said to much applause at last year’s Labour conference. This has fast grown into a manifesto, put to his party on Tuesday.

The ramifications here are profound. Mr Blair has won so much Tory support because he is showing courage and risking everything. This admiration will outlast the Iraq invasion because risk is Mr Blair’s new policy for both international and domestic issues.

It is quite possible such voters will replace those in the Labour Left who tear up their membership cards as he sends troops to war. As Thatcher found out, strength of leadership can be a political party in itself.

For the 294 Labour back-benchers, they will next week be asked to nail their colours to the mast. Every one will emerge from that lobby with a clear label: pro-Blair or anti-Blair.

There will be no refuge for the MPs who are pleased to have been brought to power by Mr Blair - but keep winking at their grassroots by signing the odd motion attacking his policy.

Next week, Mr Blair will ask his party if they are ready for a new kind of leadership. The question is so audacious because the answer may well be "no".

Last time, there were 122 rebellions - with about 40 more Labour MPs who say they kept their powder dry for the "big one". That means next week.

It will take 148 rebels to deprive the Prime Minister of his back-bench majority, 165 to leave him relying on the Conservatives for survival and 245 to make him lose the vote altogether. The Prime Minister could not survive such a defeat. But if he wins, and the war goes well, he will have taken his party into a new paradigm. This is the prize for which he is now willing to risk everything.

"There are decades when nothing happens; and there are weeks when decades happen." So wrote Lenin when he was living in exile before the 1917 revolution.

In Britain and the world, we are living through such weeks.