Ghost of a flea

War leaders do this kind of thing partly because they feel they need the powers, and partly to stop the targets of their detention from eventually being lynched. And this is the aspect that civil libertarians sometimes miss. It feels necessary to point out that, just as some young Muslims may be said to be "angry" and therefore prone to do bad things, so may ordinary British people become angered by the threat or reality of being blown up on their own buses. And they too could, if stirred up enough by some newspapers, by some fringe political parties, by populists and by the sight of men such as Bakri Mohammed sticking two fingers up to us, turn nasty. That’s something that Mr Blair knows too.

He knows, because this is what he is good at, that people wonder why the French can take action when we apparently can’t, and yet no one suggests that Paris is at the heart of an authoritarian state. Or that the German interior minister, Otto Schily, can demand whether it is "really unthinkable that they (rogue preachers) should be isolated for a period of time" without being denounced as a born-again totalitarian.