Why Blair will convince doubters

The timing looks bad for Tony Blair. This week, the trade unions will have their say about Iraq. In three weeks, Labour gathers for its annual conference. The Prime Minister would doubtless prefer to confront neither audience just now.

However, ill-timed crises are among the hazards of high office. The domestic challenge facing Mr Blair between now and next month is to stop the Labour movement either descending into fratricide or ganging up in overwhelming numbers against him - and for him to do so without abandoning his determination to destroy Iraq's weapons of mass destruction.

What are his chances? Here are three reasons why he could succeed. First, his most vociferous critics advance a number of weak arguments. They express concern for the principles of international law.

In fact, they reject force against Iraq in any circumstances. They do not want the UN to take action. They would be appalled if it did. Arguments about legality are a smokescreen. This became clear in Channel 4's "trial" on Saturday of the war against terrorism. One of the "prosecutors", Gary Younge, argued that everyone should be presumed innocent until proved guilty - and there was no proof that Saddam Hussein really is developing weapons of mass destruction.

However, this is mainly because the Iraqi leader refuses to admit UN arms inspectors. Under Mr Younge's principles, Saddam Hussein is, at the very least, guilty of obstructing the course of justice.

If a man with a record of criminal violence bars his house to detectives in possession of a search warrant, most of us would support police action to effect forcible entrance. So Mr Blair could attack his loudest critics for muddled thinking.

Secondly, he has a chance to win over the far larger group of people worried that the US might act outside international law. This group regards Saddam as a menace who needs to be stripped of his capacity to unleash weapons of mass destruction. However, it believes that legal principle and political prudence require action to be authorised by the UN.

Mr Blair agrees. This is why he has been persuading President Bush to involve the international community. The two men are now trying to build a sufficient consensus to pass a tough resolution in the Security Council. As long as the Prime Minister continues to make the UN his preferred mechanism for tackling the crisis, he should be able to satisfy enough MPs to thwart any attempt to impose serious damage at their conference.

Third, Mr Blair now has a real chance to regain the initiative with the wider public. Last week I argued that time was running out, and that he needed to act swiftly to shore up public opinion. In his press conference in Sedgefield he accepted this analysis. Hence his decision to bring forward the publication of the dossier on Iraq's development of chemical, biological and nuclear weapons. What is now clear is that the electorate is not opposed to war in all circumstances, but only to a high-handed lynch-law assault by the US.

The latest YouGov poll, for yesterday's Independent on Sunday, shows that 55 per cent agree that Saddam "poses a serious threat to world peace", that 74 per cent would support a UN military operation against him, and that 68 per cent think Britain should contribute troops.

So Mr Blair has something to build on. The time may come when tough choices must be made - if, for example, the UN sets a deadline for Iraq to readmit arms inspectors, that deadline passes without Iraq letting them back in, and the Security Council then fails to agree effective action against Baghdad.

Then the Prime Minister will face the toughest decision of his life: whether to help the US act outside the UN, or allow Saddam to carry on mocking the world.

However, that moment, if it arrives at all, will not come until well after Labour's annual conference. Meanwhile, Mr Blair has a chance to carry most of his party and the wider public with him, now that he has started to engage the argument, rather than let it drift, as he did for most of the summer.