My spies tell me that there has been the mother and father of a row over the authorised history of MI5 written by Prof Christopher Andrew of Cambridge university. Defence of the Realm was published this week despite serious concerns in some parts of Whitehall and, it seems, among some politicians. So fierce was the lobbying there were even fears it might not come out at all, though happily such fears have proved unfounded.

It was not the MI5 people who caused the difficulties. Professor Andrew says that when it came to getting clearance for the finished manuscript MI5’s concerns were “appropriate” – unlike some other government departments.