Leading article: A welcome success - but the future remains bleak

No one with the best interests of the Iraqi people at heart could possibly mourn the passing of Abu Musab al-Zarqawi. The Jordanian insurgent leader, who this week met his end in a US air strike, was responsible for countless atrocities in Iraq over the past three years.

The kidnapping and beheading of Western hostages, including the British engineer Ken Bigley, were Zarqawi's handiwork. He was also behind many of the suicide bombings that have brought death on a massive scale to the country. His attacks on the Shia civilian community were prosecuted with horrific zeal. No one should be in any doubt that Zarqawi has a great deal of innocent blood on his hands - and that, if he had lived, he would have added to this.

There remains doubt as to who can legitimately take the credit for finally tracking Zarqawi down. But his death is a substantial boost for Iraq's new government. The new Iraqi Prime Minister, Nouri Maliki, can now point to perhaps the first real achievement on the security front of any Iraqi-led administration since the toppling of Saddam Hussein three years ago.

The announcement of Zarqawi's death coincided with the news that two important government posts - defence minister and interior minister - have at last been filled, after months of dispute. For the first time since parliamentary elections last December, Iraq now has a complete government. But does all this mean Iraq is turning a corner, both politically and militarily, as some have inferred? Optimists should beware. There have been a good many "turning points" in Iraq in recent years, from the capture of Saddam, to the appointment of Mr Maliki. Bitter experience suggests that this will be one more turning point at which Iraq fails to turn.

We must also not swallow the analysis, pushed so heavily by the US in the past, that Zarqawi was al-Qa'ida's sanctioned representative in Iraq and the mastermind of the entire insurgency. In a sense, it suited both Zarqawi and the Bush administration for this to be widely accepted. As far as Zarqawi was concerned, being demonised by the US boosted his stature in relation to other insurgents. Meanwhile, it enabled the US to shift the blame for the insurgency on to foreign terrorists, like Zarqawi. In this way the attacks on US and Iraqi government troops could be neatly bracketed with President Bush's broader "war on terror".

The reality of the Iraqi insurgency is a much more damning reflection on the actions of the Bush administration. There are undoubtedly many foreign fighters in Iraq. Robert Fisk's report this week on the families of Palestinians who have gone to Iraq to join the insurgency is confirmation of this. It is also true that Zarqawi was a figurehead of sorts for the insurgency, largely due to his willingness to use the internet to publicise his killings. But the US seems determined to ignore the fact that foreign fighters, Zarqawi included, simply could not operate without the broad support of Iraq's five-million-strong Sunni population. There is no reason to believe that others will not now come forward to take Zarqawi's place - or that the insurgency will peter out without the charismatic force of his personality.

The presumption of the Bush administration before the invasion, that US forces would be gratefully welcomed by the Iraqi people, has never looked more arrogant than it does today; nor the prospect of an honourable withdrawal of US and British troops more distant. An illegal invasion, followed by an occupation of criminal incompetence, has resulted in an utter catastrophe. So while the demise of one of Iraq's butchers is, of course, welcome, let us be under no illusions that the nightmare of this country is about to end.