A fatal error.

Of course, making fatal errors isn't half as bad when they're fatal to someone else.

I stand by what I said here:

As long as [the police] insist that they are absolutely the only people allowed to act against criminals and to defend the public, they take on the responsibility of doing the job perfectly — not just very well, but perfectly.

That's hardly apposite, though: ordinary members of the public have a role to play in fighting terrorism, and that role probably doesn't involve getting into gun-fights with terrorists. This is one area where the police and security forces are right to insist that they hold a monopoly. (Though I can't help but wonder: what if a member of the public pulled a gun on the Tube and shot a real suicide-bomber in the head, preventing detonation and saving lives? How would the police's attitude towards their own killing of an innocent man compare with a non-police killing of a terrorist?)

They seem to have the right attitude here: they are ready and willing to shoot suicide bombers dead rather than letting them succeed. I for one am glad to hear it. It's a pity that the first time they act on this new policy turns out to be the wrong time, but I hope that, in time, they will kill the right men. Jean Charles de Menezes acted very stupidly indeed, and it is a great shame — and surely not his fault — that he did so in a situation in which stupidity can kill.

There is one thing, however, that the police have done badly wrong here. Why the hell wasn't the new policy announced? Had there been bulletins on the news last Thursday, announcing that the Met were going to shoot anyone who refused to co-operate, would Mr de Menezes have run from the police on Friday? And, if he had, how much sympathy would we have for him? Would the Brazilian diplomatic corps be giving the British Government quite such a hard time?

The Met's new policy towards terrorists is the right policy, but it should not have been unleashed on an unsuspecting public. I am sure there will be further changes in policy over the coming months. From now on, the police had damned well better start warning us.