The UN murderers must never be allowed to achieve their aim

The murder of Sergio Vieira de Mello and his many United Nations colleagues on August 19 is a catastrophe. It is the international version of September 11, and it makes it infinitely harder for the UN to help in the reconstruction of an independent Iraq. Which is just what the murderers intended.

The numbers of dead bear no comparison. But the evil men who carried out this attack murdered more UN officials than in any other assault upon the organisation since it was created after the Second World War.

Just as September 11 was an attack upon America, August 19 was an attack, by the same sort of people, on the international system.

We have to see it as a direct assault upon the principles of international civil society that we have tried to create since 1945. It was an attempt to murder not just fine men and women – the UN had sent its "A team" to Baghdad - but also the humane values that the UN, for all its shortcomings, represents and strives to fulfil.

Sergio Vieira de Mello was one of the most brilliant diplomats that the United Nations has ever produced. He was spoken of as a possible successor to Kofi Annan, who is widely thought to be the best leader the UN has ever had, but who is now suffering the murder of his friends and colleagues.

Among those murdered with Sergio were the superb, long-serving Nadia Younes of Egypt and such gifted young officials as Rick Hooper from the US, Fiona Watson from Britain, and Ranillo Buenaventura from the Philippines.

I had known Sergio for many years and watched him work in Cambodia, in the Balkans, in East Timor and in Africa. He was a joy to be with – a magnetic personality. He was intensely serious about his work, but he could also laugh and make fun of himself.

He was debonair, immaculate, remarkably handsome and had a smile that could launch a thousand ceasefires. Women adored him; men admired him.

A US senator once said:"Whenever I meet Sergio, two things happen. First, I feel poorly informed. Second, I feel poorly dressed." I have never heard anyone speak ill of him. People talked of "Sergio's magic".

In Cambodia in the early 1990s, he arranged the repatriation of 400,000 refugees with consummate skill, persuading recalcitrant communist officials to do as they were bid so charmingly.

In Bosnia, I went with him once to meet the egregious Serb leader, Radovan Karadzic. He was a psychiatrist of sorts and Sergio gave him the latest edition of the New York Review of Books, in which the cover story was about a war between psychiatrists.

Having charmed Karadzic, Sergio then sat down to hours of tough talks with him. We used to joke that the only possible title for his eventual memoirs was "My friends the war criminals". Now he will never write the book, because the war criminals got him.

In East Timor, he led the tiny community out of the wreckage left by Indonesia and into full independence. For this he and the UN were denounced by Osama bin Laden. Why? Because they had helped a basically Christian community secure its freedom from its Muslim occupiers.

There is speculation that his murder may have been the revenge of al-Qa'eda. But whoever committed this terrible crime was trying to stop the world giving Iraq a chance - its only chance - of decent government.

Sergio saw the UN's role as laying the foundations of civil society. He said: "The people of Iraq have suffered enough. It is time that we all... come together to ensure that this suffering comes to an end... We must not fail."

He said that he understood that the Iraqis did not want to be occupied. He quickly won the confidence of L Paul Bremer, the US administrator, and argued that Iraqis must be empowered as quickly as possible. He was a very good friend to the Iraqi people – that is why the killers targeted him.

The murderers do not want the international community to succeed in building a decent Iraq – they want first chaos and then a new despotism, either Ba'athist or Islamic, to prevail.

This is an abridged version of an article, which appeared in the Wall Street Journal Europe on 22 August and the Daily Telegraph on 26 August 2003.