Leading article: Now we need some straight talking from the politicians

The ideological underpinnings of the invasion of Iraq are beginning to break loose.

The neo-conservatives, that small group of Washington insiders and opinion formers that enjoyed such influence over US foreign policy during George Bush's first term, are beginning to distance themselves from the tragedy unfolding in Iraq. Although they were the driving force behind the use of military force to remove Saddam Hussein, a number of prominent figures such as Francis Fukuyama and Richard Perle are now dissociating themselves from the consequences of the war they did so much to bring about.

As might be expected, these recantations have not been unqualified. Most neo-cons maintain that the thinking behind the invasion was right; the flaws were in the execution. There is an element of truth in this. The aftermath of the lightning march on Baghdad was unquestionably handled appallingly. The US Defence Secretary, Donald Rumsfeld, professed to see freedom in the post-war disorder. The Iraqi army and police force were disbanded. The civil service was purged of all Baath party members indiscriminately. We now know that Washington eschewed any detailed post-invasion planning. Bloodshed and chaos were the consequence.

But the failure to plan is not the whole story, and the neo-cons are deluded if they think they can salvage their theory of a "preventive war" from the rubble of Iraq. Even before the latest outbreak of sectarian violence, the invasion had proved a terrible mistake. The manner in which the US rushed into war, with the unflinching support of our own Prime Minister, has gravely damaged America's reputation. The contempt shown by the US for international law has not been forgotten. The casus belli - that Saddam held weapons of mass destruction - has turned out to be false, fatally weakening the moral justification for military intervention. The result is that the Iraq war has stoked radicalism across the Muslim world and boosted Islamist terrorism beyond anything even the leaders of al-Qa'ida probably hoped for. By any objective standard, the invasion of Iraq has made the world less safe. That is something to consider as we approach its third anniversary.

The present trajectory of Iraq itself has also to be considered. Last month's bombing of the Shia shrine in Samarra has pushed Iraq to the brink. Yesterday, 24 bodies were discovered in Baghdad. Mr Bush and Mr Blair point out that Iraq has its first democratically elected government. But Iraq's government, hampered by allegations of corruption and largely confined to the Baghdad "Green Zone", is barely worthy of the name. The central administration remains so weak that Washington has quietly dropped its intention to reduce its 130,000 troop-strength this year. The US ambassador to Iraq, Zalmay Khalilzad, admitted this week that the removal of Saddam Hussein had opened a "pandora's box" that could precipitate all-out civil war.

If only we could get such honesty from the ambassador's political masters in Washington. But the Bush administration has steadfastly refused to admit any error in either the principle or the practice of its Iraq adventure. And the arrogance that led it casually to disregard the verdict of the United Nations is still very much in evidence. We see it in Mr Rumsfeld's refusal to close down Guantanamo Bay. We hear it in the weasel justifications for kidnapping and torture given by the US Attorney General on his visit to London this week.

We welcome the fact that the ideological architects of the invasion of Iraq are beginning to admit their mistakes. But the nightmare into which their arrogance and misplaced idealism helped plunge us three years ago is far from over.