Our boys will play very little part in any war. But that is cold comfort

As Tony Blair was restating Britain's approach to Iraq during Prime Minister's Question Time last week, an MP shouted out "What's it got to do with us?". The MP happened to be a Conservative, enabling Mr Blair to mock the largely hidden divisions on the Conservative benches over the looming war. He then gave an answer to his anonymous heckler: it was in "Britain's national interest" to take a tough line on Iraq.

As with many of Mr Blair's seemingly definitive answers, this one raised many more questions, not least of which is "Why is it in Britain's national interest?". There is no need to be a right-wing "little Englander" to question Britain's position as it stands, yet again, "shoulder to shoulder" with the United States.

For President Bush, the advantages of having the support of Britain are obvious. Mr Blair provides symbolic cover for military action that will be undertaken largely by the US. If there is a war, the US will fight it. Britain's military contribution will be tiny. But from a British perspective, this is precisely where the problems begin.

The choreography of war will give the false impression that Britain is playing a much bigger military role than it really is, distorting again the way this country is perceived and sees itself. It is painfully easy to envisage the opening hours of the war on our television screens. President Bush will give an address from Washington that will be broadcast around the world. Minutes later, Mr Blair will do the same from Downing Street, with a big build-up from assorted political correspondents outside adopting their most sombre tones: "Mr Blair had a 30-minute phone conversation with the President this afternoon...".

This is what happened on the opening night of the war in Afghanistan last year. What neither Mr Blair nor the sombre correspondents mentioned then was that Britain's military involvement was negligible, confined to the odd symbolic missile. The impact of such misleading choreography will be discernible immediately next year, as it was during the war in Afghanistan. Much of the media will trumpet "our boys" and Britain's willingness to fight compared with the cowards in the rest of Europe. Parts of Britain will preen themselves on our country's greatness, celebrating the special relationship with the US. Inadvertently or deliberately, they will feed scepticism about Europe and delusions of grandeur about Britain's place in the world.

Externally, two reactions are likely. Parts of Europe, especially other northern European countries, are already bewildered by Britain's position. Here is a country incapable of running a train on time, with a lower quality of life than many of its neighbours, that somehow contrives to stand "shoulder to shoulder" with the world's only superpower.

The prospect of another war reinforces the stultifying ambiguity about Britain's place in the world. Is it at the heart of Europe? Is it the unswerving ally of the United States? Is it a major military force even with a relatively puny military budget?

This is minor stuff compared with the other external consequence. Britain is bound to be seen as an even more tempting target in that other more dangerous and elusive conflict, the war against terrorism. Several attempts have been made to conflate the possible attack on Iraq and the on-going battle with al-Qa'ida and its ill-defined allies. None of the attempts has been convincing. Britain is in the bizarre position of preparing for a possible terrorist attack while taking a lead in a venture that is likely to provoke more terrorism.

Mr Blair's role in this ominously fluid situation defies easy categorisation. He is much the most pro-European prime minster since Ted Heath and, in my view, is the only politician capable of winning a referendum on the euro. Yet, well into his ninth year as party leader and sixth as Prime Minister, Britain is as strong an Atlanticist as it was under Margaret Thatcher and still a long way from being part of the euro and therefore at the centre of Europe.

In relation to Iraq, Mr Blair's role is equally awkward to categorise. Undoubtedly, he has steered Mr Bush away from unilateralist action and towards the UN. He has played his small hand with considerable strategic skill. But to what end is he playing his hand? The evidence suggests that he decided long ago that military action against Iraq was required. I would be surprised if he has ever privately challenged Bush about this. I suspect that their discussions have focused more on the best means to bring this about.

The most revealing evidence for this comes from Mr Blair himself. During his prime ministerial press conference in September he stated: "The UN has to be a route to deal with this problem, not a way of people avoiding this problem." Here was another Blairite statement that sounded definitive, but actually raised a thousand questions. The tone was internationalist, yet the approximate translation of these words was "The UN matters, but only if it agrees with our point of view". The contortion reminds me of what Mr Blair once said as Leader of the Opposition to a local government conference. He told his excited audience that "A Labour government would give more freedom to councils as long they exercised that freedom responsibly". The audience was too excited to recognise the nuance: councils could do what they wanted as long as it was what a Labour government wanted them to do.

Indeed, Mr Blair's approach to war has broader echoes of the build-up to the 1997 election victory. Between 1994 and 1997 he was a tactical genius, building up a coalition for a landslide that brought about a necessary regime change. He was much less clear about the policies that would follow the victory. Words such as "modernisation" and "reform" obscured a lack of detail. Now he has contributed to the construction of an international big tent, but what happens once the war is "won" remains vague.

Mr Blair responds angrily to this question by saying that he cannot understand why some people agonise over the removal of a tyrannical monster. But that is an answer to a different question. Given the risks involved, it is not enough to welcome the prospect of Saddam's removal without having a clear sense of the aftermath. Endless vague promises were made by international leaders about rebuilding Afghanistan after the war. Already there are signs that the international community, especially the US, has lost interest, that it has moved on.

The heckling MP asked a valid question. Why is it in Britain's interest to play such a high-profile role over a cause that is still dangerously vague? Mr Blair needs to give much fuller answers after the Christmas break.