Steve Richards: The PM will do well to find a successor of his calibre

Analysis

The departure of Andy Coulson is highly significant for a single reason.

In what is an almost impossible job he delivered for David Cameron. Very soon after Coulson arrived to work with Cameron in opposition, media coverage of the Tory leader started to improve considerably. Until his appointment Cameron's media strategy was based largely on the naive assumption that appearances on television news bulletins would be enough to project a message. The strategy overlooked the centrality of newspapers in reflecting and shaping the way a leader is perceived. Coulson addressed the gap quickly, most famously with his former employers at News International. The Sun and The Times became cheerleaders for Cameron and George Osborne, but some other newspapers became more positive too.

Equally important, Coulson did not seem attracted by the idea of becoming famous. To some extent Labour's senior spin-doctors, on both the Blair and Brown wings, became intoxicated with their own public prominence. They knew the dangers of fame but part of them enjoyed their weird celebrity. Coulson stayed in the background to such an extent that the BBC was struggling yesterday to find much footage to illustrate the drama of his sudden departure. Such public restraint is part of the spin-doctor's art. As Alastair Campbell told one ambitious applicant for the post of his deputy when Labour was in power: "This job is the least glamorous in politics."

It is also one of the most difficult and arduous, projecting politicians on to a media largely untroubled by nuance. Coulson made some big errors. At times he spun an image of Cameron for the right-wing tabloid newspapers that was so at odds with other more "progressive" messages the Tory leadership was seeking to project for the benefit of non-Tory newspapers that the overall impact was incoherent. Cameron's senior adviser, Steve Hilton, was known to despair at times at Coulson's priorities.

Arguably Coulson also made a historic misjudgement in giving the go-ahead to the televised debates during the last election. Cameron had most to lose, and he proceeded to lose it, or at least a lead in the polls that implied an overall majority. Broadcasters were surprised at Coulson's laid-back approach during the negotiations. Perhaps he was too laid-back more widely in his commitment to the Conservative party. In contrast to Campbell he arrived solely as a journalist and not as a tribal party supporter. But on the whole he was a substantial asset carrying out tasks that leaders never fully understand. If he had not been an asset Cameron would not have kept him for long. There will be much comment that Cameron made a colossal misjudgement in appointing Coulson in the first place, given his earlier resignation as editor of The News of the World. Some will argue that Cameron proceeded to make an even greater misjudgement in allowing Coulson to stay when he became a major front-page newspaper story. I disagree. I can understand fully why Cameron made both moves and do not believe they reflect badly on him.

The projection of a message in the media is central to a leader's survival. Ed Miliband's mediated public figure has become sharper and more agile since the appointment of his two spin-doctors at the end of last year. Some in the media affect to view so-called "spin" with disdain, but they cannot do without it, and attack leaders who try to do without highly accomplished journalists. One of Gordon Brown's fatal errors was not to appoint a journalist to work with him. As a result his chaotic operation showed no understanding of the rhythm of news.

Cameron will need to find a replacement who reads those rhythms and who is also willing to work seven days a week. Blair once told me he thought Campbell was a "genius" in his ability to read news stories, those which would run and those which would disappear quickly. In the end like Coulson, Campbell became a running story and departed. The fate of those who mediate between politicians and the media at the highest level is to become a story that damages those they work for, a strange ironic twist in an almost surreal vocation.

The urgency to find a successor is greater for Cameron at a time when his government erupts with policies that have not been fully thought through and contain within them potentially explosive stories. To give one example it will take a spin-doctor of genius to explain why the reforms of the NHS are a triumph when an inevitable story breaks about a patient that has suffered from poor care. "There is no connection between the reforms and this particular incident," he or she will insist. Even in a media heavily biased in favour of the Conservatives, the proclamations are unlikely to break through the frenzy.

But the need to proclaim is obvious and in spite of the demands of the job, few journalists can resist an invitation to the heart of power. Cameron will find a successor. He or she will need to be a titan.