Some of this speculation has been ridiculously sweeping. In the past 100 years, Britain has been involved in six wars of a military and political scale this size or bigger. These were the First World War, the Second World War, the Korean War, the Suez Crisis, the Falklands conflict and the Gulf War. The effect on the Prime Ministers concerned has been variable. David Lloyd George continued in office but in a coalition in which he was the prisoner of the Conservative Party. Winston Churchill was ejected by the voters. The austerity associated with Korea contributed to Clement Attlee’s narrow defeat in 1951. Anthony Eden was deposed by his own party after Britain’s withdrawal from the Suez Canal. Margaret Thatcher’s triumph in the South Atlantic enabled her to secure personal control over party and country (but Mr Blair had that from the moment he entered Downing Street). If the Gulf War allowed John Major to stamp his authority on Britain, I must have missed that moment. History, in short, does not indicate that Iraq will utterly transform domestic life.

This does not mean that politics has not changed at all as a consequence of this conflict. The shift, though, is subtle and sophisticated. There are three broad areas worth exploring. The first is the impact of the character and duration of the war. The second is recent events unrelated to and obscured by the conflict but which, when drawn together, are significant. The third is the influence that Iraq has had on certain individuals and issues.

While he would have preferred a very short war, Mr Blair may find that a shortish war is of more benefit politically. The conflict has lasted long enough to make a deep impression on the electorate in the way that a three-day dash to Baghdad by — overwhelmingly — US forces would not have done. The manner in which our soldiers have handled themselves in and around Basra has been widely admired at home and has reinforced the sense of the Prime Minister as a civilising, moderating and restraining influence on the White House. The behaviour of the Iraqi regime, by contrast, has, I conclude, convinced many who initially opposed the war that it is legitimate. In a strange sense, therefore, Mr Blair has managed, to borrow a phrase of Dick Morris, President Clinton’s pollster, to “triangulate” between President Bush and Saddam and appear that rare item, the reasonable face of warfare. If so the “Baghdad bounce”, in terms of his own personal ratings, may turn out to be somewhat larger than expected.

The “dogs that didn’t bark” factor is also important. The Iraqi crisis has all but wiped every other political development of the past three months off the radar. That does not mean that they will be electorally inconsequential. Since January the following events have occurred: the firefighters’ dispute, which threatened to torpedo government policy towards public sector pay and reform, is in absolute disarray with the Fire Brigades Union plunged into civil war; the coldest winter in most parts of Britain for more than a decade did not bring the NHS to its knees as a milder snap did three years ago; fears of an outbreak of terrorism at home have proved unfounded; the congestion charge in London, which many Labour strategists feared would be a catastrophe from which ministers could not escape some blame, has been introduced without mayhem; and Northern Ireland is edging, as Mr Bush’s visit to Belfast may testify, towards a dramatic political breakthrough. Mr Blair has every reason to be satisfied.

The final element is the political “displacement effects” of this conflict. These have been threefold. Whatever prospect there was of a euro referendum this year has disappeared completely. Mr Blair and Gordon Brown will now, I believe, reach an amicable compromise on a subject which once looked as if it might be the end of their alliance. The Chancellor will produce a “not quite yet” verdict which allows the Treasury to re-examine the evidence on an annual basis. The Prime Minister will be able to claim, accurately, that the single currency has not been ruled out before the next election while Mr Brown will consider, equally correctly, that such a ballot remains distinctly unlikely. Meanwhile Kenneth Clarke, the man who Labour would least like to lead the Conservative Party, has all but blown his brains out by the stance he took before war started. There was, at the end of last year, a consensus emerging among many Tories that the pragmatic case for Clarke was irresistible. Mr Clarke has managed to destroy it. And the war has also left Charles Kennedy with a conundrum. His anti-war rhetoric may have attracted middle-class lefties into his camp but, as shrewder Lib Dem MPs such as Mark Oaten and David Laws will be aware, this will make it harder for him to reposition his party towards the political centre.

Low turnout may mean that Labour is destined for an uncomfortable set of local and devolved elections. One should not conclude from this, however, that the “Baghdad bounce”, the “dogs that did not bark” and the “displacement effects” are irrelevant. They will have a real impact on the conduct of British politics for the remainder of this Parliament. Mr Blair will, I suspect, have rather more time and reason to savour his triumph over the pundits than Mr Heath ever managed.

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