Why are wars not being reported honestly?

Dan Rather, who was the CBS news anchor for 24 years, was less reticent. "There was a fear in every newsroom in America," he told me, "a fear of losing your job ... the fear of being stuck with some label, unpatriotic or otherwise". Rather says war has made "stenographers out of us" and that had journalists questioned the deceptions that led to the Iraq war, instead of amplifying them, the invasion would not have happened. This is a view now shared by a number of senior journalists I interviewed in the US.

In Britain, David Rose, whose Observer articles played a major part in falsely linking Saddam Hussein to al-Qaida and 9-11, gave me a courageous interview in which he said, "I can make no excuses ... What happened [in Iraq] was a crime, a crime on a very large scale ..."

"Does that make journalists accomplices?" I asked him.

"Yes ... unwitting perhaps, but yes."

What is the value of journalists speaking like this? The answer is provided by the great reporter James Cameron, whose brave and revealing filmed report, made with Malcolm Aird, of the bombing of civilians in North Vietnam was banned by the BBC. "If we who are meant to find out what the bastards are up to, if we don't report what we find, if we don't speak up," he told me, "who's going to stop the whole bloody business happening again?"

Cameron could not have imagined a modern phenomenon such as WikiLeaks but he would have surely approved. In the current avalanche of official documents, especially those that describe the secret machinations that lead to war - such as the American mania over Iran - the failure of journalism is rarely noted. And perhaps the reason Julian Assange seems to excite such hostility among journalists serving a variety of "lobbies", those whom George Bush's press spokesman once called "complicit enablers", is that WikiLeaks and its truth-telling shames them. Why has the public had to wait for WikiLeaks to find out how great power really operates? As a leaked 2,000-page Ministry of Defence document reveals, the most effective journalists are those who are regarded in places of power not as embedded or clubbable, but as a "threat". This is the threat of real democracy, whose "currency", said Thomas Jefferson, is "free flowing information".

In my film, I asked Assange how WikiLeaks dealt with the draconian secrecy laws for which Britain is famous. "Well," he said, "when we look at the Official Secrets Act labelled documents, we see a statement that it is an offence to retain the information and it is an offence to destroy the information, so the only possible outcome is that we have to publish the information." These are extraordinary times.