It was, as has been noted elsewhere, a risky move, but it looks likely to prove an effective one. For a broadcaster of Jon Snow's experience and stature to be left so obviously floundering, making small but key errors in his questions and committing that cardinal sin of TV talk - umming and ahing - was a victory the Downing Street PR boss will have savoured throughout the weekend.
The Channel 4 appearance sums up the manner in which the Government, which just two weeks ago was apparently reeling from allegations of having 'sexed up' the dossier on Saddam Hussein's weapons of mass destruction capability, has fought back. Taking the battle to its critics while subtly shifting the parameters of the debate was a PR masterstroke - it makes the opposition question the legitimacy of its own position, even as it is busy trying to anticipate (or guess) what approach Downing Street will take next.
That approach has been, as in previous, similar spats, to latch on to minor flaws in the opponent's argument, focusing on them to the extent that they become the entire case to defeat, rather than an element of it. By inflating a minor but beatable point - in this case, the unmade claim that Campbell personally lied about the 45 minutes to armageddon argument - the well-practised spin machine at the heart of power seems content to take on all comers.
In exercises so far, of course, it has yet to come up against as formidable a foe as the BBC. It, too, has its share of wily PR operators - led by communications head Sally Osman - who understand what motivates the media and how to frame a message so it captures the public's imagination.
Despite this, there is a looming PR problem for the BBC, in that accuracy and truth are its unique selling points. As director of news Richard Sambrook's letter to Campbell made clear, reporting stories on the basis of one source goes against the spirit, if not the letter, of the Corporation's producer guidelines.
And for the BBC, it is not just popular support at stake. If its commitment to accuracy fails to stand up to scrutiny, its contribution to public service broadcasting does so, too. On that is based the licence fee, and therefore the organisation's very existence.
Amid the ongoing melee, therefore, one thing is certain: of the two most influential media institutions of our time - Campbell and Auntie - one is set for the mother of all PR disasters.
At the time of going to press, it does not look likely to be Campbell.