Abu Musab al-Zarqawi was a murderer, not a martyr. The majority of his victims in Iraq were fellow Muslims. He openly sought to trigger a civil war between Sunni and Shia followers of his faith. In the case of Christians who fell into his clutches, he combined the barbarism of centuries past with the tools of contemporary technology. Via video and the internet he boasted that “cutting off the heads of the criminal infidels is implementing the orders of our Lord”. Few tears will be shed for his passing. Far too many have been cried for his casualties. George W. Bush and Tony Blair were certainly entitled to welcome that he is no more.

The broader question is the impact that his death will have on Iraq. There have to be many qualifications to any prediction. The so-called insurgency has not been the work of one man and, as attacks in Baghdad yesterday again grimly illustrated, al-Qaeda affiliates are not alone in plotting carnage. His organisation will have planned a number of other atrocities that, alas, will proceed despite his removal. It will be weeks, perhaps months, before it is possible to assess the effect that the end of al-Zarqawi will really have.

Yet even so, the event is, potentially, of enormous significance. His demise may well come to be seen as far more important than the capture of Saddam Hussein. Al-Zarqawi has been the face of terrorism in Iraq and the inability of the authorities there to capture him mocked the idea that they had secur-ity under control. He has operated in Iraq for the better part of three years and no successor will have the same vicious standing with his peers. He will be difficult to replace.

Terrorist bodies are also, despite the claims they make of popular backing, top-down institutions. They invariably depend upon the charismatic and cunning leadership of a small number of individuals. As Israel showed when it decapitated the hierarchy of Hamas in 2004, the “military” capacity of terrorists can be decimated by the loss of a few crucial people. Al-Zarqawi is in this category. All the evidence implies that he was the brains as well as the gloating voice of al-Qaeda in Iraq. His group will endure a period of disarray.

The new Iraqi Government, led by the Prime Minister, Nouri al-Maliki, has to exploit this opening relent- lessly. Mr al-Maliki has proved to be a shrewd operator and has presented himself to the Iraqi people as the man who can maintain national unity and restore law and order. The removal of al-Zarqawi instantly renders those promises more plausible. Terrorism took root in Iraq because zealots sensed a political vacuum after the toppling of Saddam Hussein and moved ruthlessly to fill it.

There is today a new vacuum in the ranks of the extremists. The administration in Baghdad must now use maximum force to defeat its foes.

Such an effort would be popular with the bulk of Iraqis — be they Shia, Sunni or Kurd. They are sick of mayhem orchestrated by malicious out- siders and extremists and want to build what can be the most prosperous and democratic society in the region.

While the relief expressed at the death of al-Zarqawi in London and Washington is understandable, it is in Iraq where the difference will be greatest. It would be premature to hail what has happened as a turning point for this long-suffering country. But this is a moment of extraordinary opportun-ity and it must be the mission of Mr al-Maliki and his allies to ensure that it becomes a turning point.