It is hard to judge the worse villain: Greg Dyke or Alastair Campbell

Mr Campbell and Mr Dyke, from being early allies, now find themselves in antagonism. Yet they still have much in common

Alastair Campbell seems to be sincere in his indignation. Then again, in Tony Blair's Downing St, they are all good actors. Moreover, even assuming that Mr Campbell is innocent - for once - it may suit his purposes to have this row, which has distracted public attention from much more important matters.

Equally, though the BBC now feels that its reputation is under threat, it too may benefit from the terms of this engagement. Mr Campbell was Bob Maxwell's loyal adjutant. A judge described him in court as an unreliable witness. There is a limit to the damage which he could inflict on anyone's reputation. The BBC will survive the Campbell threat, though that should do it less good than it might think. There are far graver charges which this brouhaha is obscuring, to which it has no defence.

First, the Government's failings. The real charge against Mr Blair and his henchmen is not that they sexed up an intelligence dossier. It is that they misled the British people.

We British have never been a militaristic race, but we are warlike. There is no reluctance to shed blood in a just cause, especially when most of it will be enemy blood. When conflict looms, our Prime Ministers cease to be party leaders and become the nation's leader.

Mr Blair should have invited the British people to trust him at a difficult moment. He should have told us that he had decided to go to war against Iraq for a number of compelling reasons, including the likelihood that Saddam possessed or would shortly acquire weapons of mass destruction (WMD). He could also have assured us that the world would be a safer and a better place after the tyrant's overthrow. As a result of all this, British forces would shortly be in combat; he as Prime Minister took full responsibility for this decision. Had the PM spoken in that way, his own position would now have been much stronger. The failure to locate WMD would not be a problem; it would not even matter very much if it turned out that there had been none.

Tony Blair did not speak in such terms. Instead, he fell short of national leadership, for two unworthy reasons, plus one lamentable misjudgement. First, he did not trust his party. In order to ensure that he had enough Labour votes in the Commons he over-egged the WMD question. This was an error. In that final debate before the war, he was in a mood to speak powerfully. An accurate speech could have been no less compelling and his whips would have delivered him the vote.

Second, he did not trust himself. Far from approaching the Iraq conflict in a cold-eyed, clear-headed fashion, he was in a heightened and strained frame of mind. Hence his seizing on misleading simplicities, such as a 45-minute deployment time for WMD.

Yet these are venial sins in comparison to the great misjudgement. Tony Blair did not trust the British people; he had read the opinion polls and knew that there was a problem. For once in his career, he was prepared to defy the polls, but he did so in the wrong way. Churchill, Adenauer, De Gaulle, Thatcher, Reagan and George W Bush would have addressed their advisers as follows: "You have told me what the people think. I will now tell them what they ought to think." Tony Blair could not do that. Instead he did what he had always done in the past and always got away with. He over-spun his message.

To behave like that when war is imminent and lives are at stake is a grave breach of trust. Indeed, it is hard to imagine a graver instance of bad faith by the governors towards the governed. Tony Blair has done a lot to undermine the British constitution and has often displayed a reckless disregard for the proprieties of public life; never more so than when taking the country to war on a false prospectus.

The BBC is also guilty of bad faith: doubly so, the first, lesser instance involved the corporation's approach to the Iraq war. This went far beyond impartiality. Throughout the conflict allied reverses were highlighted and the campaign's difficulties were exaggerated. The rapid, crushing victory on Donald Rumsfeld's terms appeared to take the BBC by surprise: an unwelcome surprise. One had the impression that about 90 per cent of those involved with war coverage wanted the Allies to fail. As a result, the BBC not only produced biased journalism. It produced bad journalism.

When John Birt became director general he quickly identified a problem: the political homogeneity of most of the BBC's staff. Lord Birt failed to correct that fault. Greg Dyke is not even interested in trying. A significant majority of the BBC's staff are still to be found on a political spectrum stretching from Clare Short to George Galloway: hence the coverage of the Iraq war.

But the BBC's problems go beyond Iraq. Under Mr Dyke, it is increasingly at war with its own raison d'être. The BBC exists to provide public-service broadcasting, a roll defined by its founding director general, John Reith. This does not mean that it is obliged to give the public what it thinks it wants; the BBC, too, is entitled to tell the public what it ought to want. It should not hesitate to be at odds with popular taste.

Mr Dyke is prepared to fight taste battles, but only against those who should be the BBC's natural viewers. He seems to object to any programme which the white middle classes might enjoy. Stripping out the pseudo-sociology - what class and colour is Greg Dyke? - his real objection is to thoughtful programmes for educated viewers. Here, Mr Dyke is on stronger ground when differentiating himself from those whom he is attacking. There has never been a director general with fewer intellectual interests, while his cultural horizons hardly extend beyond a football pitch.

Greg Dyke's desire to widen the BBC's appeal is laudable; not so his belief that the only way to do this is to dumb down in pursuit of ratings. The merit of the National Gallery's Rembrandts is not diminished by a low-attendance day; the merit of a public-service channel does not depend on competing with ITV and Sky. A proper BBC could still attract decent audiences and be worthy of the licence fee. But there is no justification for a poll tax to subsidise Mr Dyke's DDC: the Dumb Down Corporation.

Over the years, Greg Dyke had proved himself to be a skilful purveyor of light entertainment; that is a role for the private sector, not the public one. During his term of office, there has been a rapid reduction in political support for the licence fee, which will be accelerated by Iraq. Ultimately, however, Andrew Gilligan is not the principal threat to the BBC's finances. That arises from Mr Dyke's contempt for the Reithian mission.

Mr Campbell and Mr Dyke, formerly allies, now find themselves in antagonism. Yet they still have much in common. One wants to dumb down broadcasting: the other government. Mr Campbell is the greater villain.