In 1970, I made a film in Vietnam called The Quiet Mutiny in which GIs spoke out about their hatred of that war and its "official line/White House propaganda." The experiences in Iraq and Vietnam are both very different and strikingly similar. There was much less "embedded coverage" in Vietnam, although there was censorship by omission, which is standard practice today.

What is different about Iraq is the willingness of usually obedient British soldiers to speak their minds, from General Richard Dannatt, Britain's current military chief, who said that the presence of his troops in Iraq "exacerbates the security problem," to General Michael Rose who has called for Tony Blair to be impeached for taking Britain to war "on false grounds" – remarks that are mild compared with the blogs of squaddies.

What is also different is the growing awareness in the British forces and the public of how "the official line" is played through the media. This can be quite crude: for example when a BBC defence correspondent in Iraq described the aim of the Anglo-American invasion as "bring[ing] democracy and human rights" to Iraq. The Director of BBC Television, Helen Boaden, backed him up with a sheaf of quotations from Blair that this was indeed the aim, implying that Blair’s notorious word was enough.

More often than not, censorship by omission is employed: for example, by omitting the fact that almost 80 per cent of attacks are directed against the occupation forces (source: the Pentagon) so as to give the impression that the occupiers are doing their best to separate "warring tribes" and are crisis managers rather than the cause of the crisis.

There is a last-ditch sense about this kind of propaganda. Seymour Hersh said recently, "[In April, the Bush administration] made a decision that because of the totally dwindling support for the war in Iraq, they would go back to the al-Qaeda card, although there’s no empirical basis. Most of the pros will tell you the foreign fighters are a couple of per cent and they’re sort of leaderless . . . there’s no attempt to suggest there’s any significant co-ordination of these groups, but the press keeps going ga-ga about al-Qaeda . . . it’s just amazing to me."

Ga-ga day at the London Guardian was 22 May. "Iran’s secret plan for summer offensive to force US out of Iraq," said the front-page banner headline. "Iran is secretly forging ties with al-Qaeda elements and Sunni Arab militias in Iraq," wrote Simon Tisdall from Washington, "in preparation for a summer showdown with coalition intended to tip a wavering US Congress into voting for full military withdrawal, US officials say." The entire tale was based on anonymous US official sources. No attempt was made to substantiate their "firm evidence" or explain the illogic of their claims. No journalistic scepticism was even hinted, which is amazing considering the web of proven lies spun from Washington over Iraq.

Moreover, it had a curious tone of something-must-be-done insistence, reminiscent of Judith Miller’s scandalous reports in the New York Times claiming that Saddam was about to launch his weapons of mass destruction and beckoning Bush to invade. Tisdall in effect offered the same invitation; I can remember few more irresponsible pieces of journalism. The British public, and the people of Iran, deserve better.

John Pilger was born and educated in Sydney, Australia. He has been a war correspondent, filmmaker and playwright. Based in London, he has written from many countries and has twice won British journalism's highest award, that of "Journalist of the Year," for his work in Vietnam and Cambodia. His new book, Tell Me No Lies: Investigative Journalism and Its Triumphs, is published by Jonathan Cape in June. This article was first published in the New Statesman.

© John Pilger 2007