As Andrew Cooper departs No.10, the question for David Cameron is “Why?”

By Peter Hoskin
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Steve Hilton, James O’Shaughnessy, Tim Chatwin and, more recently, Rohan Silva. And now Andrew Cooper’s name can be added to the list of senior advisers to have departed from David Cameron’s side. According to today’s Mail on Sunday, Mr Cooper, who was appointed Director of Government Strategy in 2011, is returning to the polling company that he helped found. He will, it's said, continue to do a bit of work for the Tory party.

But why? And why now? The MoS puts it down to the presence of Lynton Crosby in No.10. As one source tells the paper, “There was never going to be room for both Andrew and Lynton” – and it’s a sentiment that I’ve heard from my own sources plenty of times before. The idea is that the modernising Mr Cooper and the blunter Mr Crosby were rubbing up badly against each other. Friction ensued.

If so, there’s a bitter sort of irony to it – as the political distances between the two men have probably closed in recent months. Not only is Mr Crosby more broad-based than the reports would have you believe, but Mr Cooper has become more hard-headed in Government. Sure, he is still, happily, a proponent of policies such as gay marriage, and he’s still the man who once branded the Tories the “nasty party”. But, thanks largely to his own polling, he’s rounded out his modernisation for the times. He was one of the main authors – philosophically, if not literally – of David Cameron’s last conference speech, with its emphasis on aspiration and economic security. And he has also urged tougher rhetoric on crime and welfare.

Mr Cooper’s departure is rather embarrassing for Mr Cameron, coming, as it does, on the back of all the other departures and of fairly recent denials that the pollster would quit. But the Prime Minister shouldn’t dwell on that, nor on the working relationship between Messrs Cooper and Crosby, whatever the truth of it. Instead, he should wonder about the systemic problems that might be driving his staff away. It could well be that, as Lord Ashcroft has warned, there are too many people treading over the same ground with no-one in charge of the overall choreography. Who really has been running government strategy? Cooper? Crosby? George Osborne? All of them? None of them? It’s sometimes difficult to tell.

If Mr Cameron doesn’t answer such questions, then it’s likely that he’ll keep shedding staff – and find them increasingly difficult to replace. Thanks to the efforts of Andrew Cooper, and of Stephen Gilbert, No.10 now has a sophisticated polling mechanism in place. But it’s the sort of machinery that requires operators.

Update, 2.30pm: The Spectator's James Forsyth, who also happens to be a Mail on Sunday columnist, has just quoted a No.10 source denying the Mail on Sunday's Andrew Cooper story. James's tweet reads as follows:

"Andrew Cooper is not leaving N0 10 according to a senior Downing Street source May go back to Populus at some point but ‘no plans’ at the mo"

To my eyes, though, the admission that Mr Cooper "may go back to Populus at some point but ‘no plans’ at the mo" is significant. There have been rumours for some time that the pollster would return to his polling company – so it could be that the Mail on Sunday were on to something with their original story, and Downing St are now trying to muddy the particulars.