Politicians tell us they acted in good faith on the road to war, and maybe they did, but that leaves a prickly question: who was so keen to prove that Saddam Hussein was an imminent threat that they forged documents purporting to show that he was trying to buy 500 tons of uranium from Niger to develop nuclear weapons? The forgery was revealed to the Security Council by ElBaradei. That was not an intelligence error. It was a straightforward lie, an invention intended to mislead public opinion and help start a war.

At the beginning of 2001, a few weeks before George Bush took office, there was a break-in at the Niger embassy in Rome. Strangely, nothing of value was taken. Months later came 9/11 and a month after that, as George Bush wondered how to get back at the terrorists, a report from the Italian security service (Sismi) reached the CIA: Iraq was seeking to buy uranium.

Disappointingly for the neocons, the CIA sent Ambassador Joseph Wilson to Niger to check the story: he reported that it was nonsense. When the story was repeated by Bush, Wilson went public. His wife, CIA agent Valerie Plame, was then outed by the White House. Hence Rove's predicament.

An organisation called the Office of Special Plans (OSP) was set up in the Pentagon by Douglas Feith, a former consultant to Israel's Likud party, to prepare for the war. In the words of Robert Baer, a distinguished former CIA man, it was a "competing intelligence shop at the Pentagon"..."if you didn't like the answer you're getting from the CIA". In short, bogus stories would get a second chance at the OSP.

A clue to the ancestry of these black arts can be found in 1980, when right-wing Republicans wanted Ronald Reagan elected. They publicised a story that Billy Carter, the then President Jimmy Carter's colourful brother, had received $50,000 (£28,000) from the Libyan government.

The story was always denied by the President and no evidence of the payment was found, but the story helped to elect Reagan. Its source? Sismi, and an associate of a man called Michael Ledeen.

Ledeen is an intriguing and enduring presence in the murkier parts of US foreign policy. He is an American specialist on Italy with a long-standing commitment to Israel. According to The New York Times, in December 2001, a few months after the CIA first heard the Niger claims, Ledeen flew to Rome with Manucher Ghorbanifar, a former Iranian arms dealer, and two officials from OSP, one of whom was Larry Franklin. In Rome they met the head of Sismi.

Some months later, the documents were published, having been sold to an Italian journalist by a Roman businessman linked to Sismi.So far, so circumstantial. One man who might well know the answer to all this is Vincent Cannistraro, the former head of counter terrorism operations at the CIA. His belief is that the documents were produced in the US but "funnelled through the Italians". When an interviewer asked Cannistraro "if I said Michael Ledeen", he reportedly replied "I don't think it's a proven case ...You'd be very close"

Ledeen, on hearing this, issued the following statement: "I have absolutely no connection to the Niger documents, have never even seen them. I did not work on them, never handled them, know virtually nothing about them, don't think I ever wrote or said anything about the subject."

It seems it wasn't Ledeen but someone close to him. So who was it who had been planning since before 9/11 to create a fraudulent casus belli against Saddam?

Norman Dombey is Emeritus Professor of Theoretical Physics at the University of Sussex and an expert on Iraq's nuclear capability.

© 2005 Independent News & Media (UK) Ltd.