Mr Bell said the proprietors had never taken the sorts of risks they had urged on British service personnel in calling for the war.
Speaking during a debate at the festival on media coverage of the war in Iraq, Mr Bell, who was a commentator for Channel 5 during the conflict, also attacked Mr Murdoch’s Sky News (in the UK) for the amount of speculation it indulged in and for “reporting rumours as fact”.
Mr Bell said: “The thing that worries me most about the coverage was its feverishness. The networks became rumour bazaars. There was spin and manipulation. Our political and military leaders also have an obligation not to deceive.”
Alan Rusbridger, the Guardian’s editor, told the thousand-strong audience that technological developments had enabled the immediate transmission of pictures and information.
They allowed the internet distribution of thousands of sources of information, including from the so-called Baghdad Blogger.
Another aspect of this war was the use of reporters who stayed with particular troops during the conflict, “embedded” in military units.
“It would be churlish to rubbish the concept of embedded reporters, having asked for it in previous conflicts,” he said.
He added that members of the Household Cavalry had been so taken by the coverage of the reporter Audrey Gillan that they claimed they had become Guardian readers.
A retired general, Arthur Denaro, was sympathetic to the media’s problems but said constant, immediate transmission of news had left the public “a touch depressed”.
Stephen Marshall, creative director of the Guerrilla fresh news Network website, based in the US, argued that there had been a higher level of debate and intelligence in the British media coverage compared with the output from the American side.
“In the US it tends to be more derivative, focusing on the lowest common denominator,” he said.
Mr Marshall stirred up debate with one member of the audience when he pointed out that the federal communications commission – the American regulatory body for the media – was chaired by Michael Powell, who is the son of Colin Powell, the serving US secretary of state.
The audience member claimed it was unfair to imply bias within the organisation just because of a close family relationship.