Anthony Seldon: Great leaders don’t need spokesmen telling them what to think and do

When Thatcher was at her strongest and most effective, Ingham was at his best. But in her last two years, she had come to rely far too much upon his advice

(Darren Diss)

In the most high-octane end of week in recent political history, alongside Alan Johnson's departure, Ed Balls's promotion and Tony Blair's second appearance before the Chilcot inquiry, the departure of the director of communications at No. 10 was the prime event.

Andy Coulson is of the same ilk as his predecessors Alastair Campbell and Bernard Ingham. All possessed brilliant talents, but fell into the trap of becoming, as heads of communication at Downing Street, not just major influences over their respective prime ministers, David Cameron, Tony Blair and Margaret Thatcher, but public figures in their own right. All three were deeply suspicious of the media and tried to micro-manage it, with inevitable results. This model is disastrous, and the great hope must be that the departure of Coulson will usher in a totally new period in relations between Downing Street and the media, which will immeasurably improve the quality of democracy and trust in Britain.

Mistrust of the media lay at the heart of the approach of all three communications chiefs. Their mistrust became a self-fulfilling prophecy. Media outlets were manipulated and spun, which did nothing to encourage them to act responsibly and take the government's agenda seriously.

All three intruded far too much into the policies of their prime minister. By doing so, they helped to make their prime minister more reactive and less prone to long-term thinking. Alastair Campbell was the worst offender by a distance. It is still not understood how much his short-term mindset damaged the entire Blair premiership, as well as trust in British public life. But it was Blair who was to blame for choosing Campbell in the first place, and for giving him so much influence.

The most telling decision Blair took came soon after he was elected Labour leader in July 1994: to persuade a reluctant Campbell to become his head of communications. Given Blair's shaky grasp of policy, his first appointment should have been a policy supremo, a figure he lacked until late in his premiership. Campbell filled some of that void, and his powerful presence shifted Blair's whole focus away from long-term thinking on to the next day's headlines, while reinforcing Blair's own suspicion of others. The result was a tight-knit coterie within No. 10, strangers to strategic policy thinking, whose inevitable dénouement was the secretive "sofa government" in the lead-up to the Iraq war, which we heard so much about yesterday.

Great leaders, like Abraham Lincoln or Winston Churchill, did not need "communications secretaries" telling them what to think and do, nor have they needed focus groups to tell them what the public is thinking and what policies they should pursue. Great leaders act from deeply held principles and inner convictions. They do not talk about having moral compasses: they possess them.

How did the No. 10 media operation descend into such a sorry state? The press office in Downing Street came into existence only in 1931. Hitherto, the limited relations with the press, and with the BBC after its foundation in 1927, had been managed comfortably by civil servants. The rise of broadcasting, and the 1931 economic crisis, were the catalysts for an office exclusively dedicated to managing press contacts. The demands of post-war reconstruction after 1945, and the burgeoning regional and overseas media, saw No. 10's media operation explode in size.

In the following years, two very different kinds of "press secretary" emerged. Career civil servants, such as the diplomat Donald Maitland to Edward Heath, or journalists already known to the prime minister, such as Joe Haines to Harold Wilson. Whatever their background, their role was the same: to link the prime minister with the outside world and to secure the most sympathetic coverage possible for what they were trying to do.

The job first began to become politicised under Clement Attlee, who chose Francis Williams in 1945, a journalist who had worked for the wartime Ministry of Information. Attlee had little taste for handling the media, and was happy to delegate much to Williams, who he left alone to do the job as he saw fit, looking at cabinet minutes, attending its meetings and talking to whomever he wanted to. The job was further politicised under Wilson, a prime minister obsessed with the next day's headlines, in the 1960s. The development of the 24-hour news cycle further heightened the role of the press secretary and the tendency for prime ministers to spend far too much of their energy reacting to immediate events.

Effective periods for British prime ministers have often coincided with unobtrusive press chiefs at No. 10. When Thatcher was at her strongest and most effective, between 1981 and 1987, Ingham was at his best. But in her last two years, she had come to rely far too much upon his advice and that of her foreign policy private secretary, Charles Powell. Ingham, with his gruff Yorkshire exterior, would prepare her daily press summary and had literally become her eyes and ears on her diminishing world. John Major was at his most effective from 1990 to 1992: having inherited a divided party, he united it to win a general election. At his side as press secretary was Gus O'Donnell, the Treasury civil servant who is now Cabinet Secretary. Although naive initially, O'Donnell was thoroughly correct in his management of the media and did not seek to intrude into decision-making, nor did Major encourage him. Gordon Brown was equally well served by Michael Ellam, who also came from the Treasury.

Blair, as he acknowledges now in his own memoirs, A Journey, squandered many of his first term opportunities from 1997 to 2001, when he enjoyed a strong economy, a large majority in parliament, and a demoralised Conservative Party. It was only from 2003 that he began to devise his own domestic policy agenda with its theme of choice and diversity, brought together by the most impressive policy lieutenant of his premiership, Andrew Adonis. It is no coincidence that Campbell disappeared from the scene at the same time, having proved incapable of eradicating the stain of "spin" from the premiership.

Cameron's new media regime needs to adopt a far more considered approach to handling the media. He needs to find a figure or figures of deep integrity and substance, who can win the trust of the media and hence the public by conveying a truthful picture of what is going on at the heart of British government. The successor regime must also be circumspect about intruding too far into policy, advising merely on the public relations angles rather than on the substance of policy itself. Great leaders know how to turn adversity to their advantage: if Cameron can use this misfortune to create a much more trusted No. 10, he will have achieved just that.

Anthony Seldon's most recent book was 'Brown at 10'