First they came for Tim Chatwin...

By Paul Goodman
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Guido Fawkes's news that Sean Worth is to leave Downing Street to join Policy Exchange names the latest addition to a growing list.

And, yes, you read that correctly: Mr Worth, a special adviser, is going to Policy Exchange - not the other way round, as one might reasonably expect.

Which is the point.  We aren't halfway through this fixed term Parliament yet, but by my reckoning the following senior figures have left Number 10 already -

• Tim Chatwin (Head of Strategic Communications)
• James O’Shaughnessy (Head of Policy)
• Andy Coulson (Director of Communications)
• Steve Hilton (Senior Adviser to the Prime Minister)
• Peter Campbell (Research)

There have also been departures from the Policy Unit, and it is claimed that Andrew Cooper, the Head of Strategy, may return to Populus. 

But whether or not this turns out to be correct, three conclusions stand:

• Not all of this talent has been replaced.  In at least one case, there has been no replacement at all - that of the admittedly irreplaceable Steve Hilton. (I accept that Mr Coulson's exit was sui generis.)

• Downing Street has had difficulty recruiting, perhaps because of tensions between the Coalition partners.  It has been reported this is so in the case of Matthew Elliott (who has some good advice of his own for Number Ten.)

• This level of departure suggests either that there are a lot of personal differences or the lack of an agreed political strategy in Number 10.  In my experience the Downing Street operation consists of very pleasant people - though it is light on staff who like and (more importantly) understand party activists and Tory MPs.  I go for the latter explanation, which Mr Hilton's departure - and the manner of it - supports.