Leading article: Intelligent police work?

We still lack a clear picture of what took place in last Friday's raid by police on two houses in east London. We know that one man, who has been arrested along with his brother on anti-terrorism charges, was shot in the shoulder. We know that the Independent Police Complaints Commission has been called in to conduct an investigation into the operation. But other than those few details, and some unconfirmed rumours about a "chemical bomb", we are largely in the dark.

The Metropolitan Police claim the raid took place after they received "specific intelligence" of a terrorism threat from the security services. We must hope they have acted responsibly and professionally. Public confidence in the Metropolitan Police has been gravely damaged by the killing of Jean Charles de Menezes in July. The consequences, if it emerges that the police have mistakenly shot another innocent member of the public, could be disastrous.

And in the meantime, the uncertainty surrounding this raid undoubtedly ratchets up the pressure on the Metropolitan Police Commissioner, Sir Ian Blair, who will have authorised this raid. At the weekend it was also reported that Sir Ian could personally face prosecution as a result of the De Menezes killing. His struggle to hold on to his job will not have been made any easier by recent events.

Last Friday's raids in London coincided with an anti-terrorism raid in Canada, where 17 suspects and three tons of ammonium nitrate were seized. This coincidence reflects a larger truth about the world's struggle against Islamist terrorism. Western societies are increasingly reliant on intelligence and police work to foil terrorist plots. The theory, expounded enthusiastically by President Bush and Tony Blair in recent years, that the front line against terrorism is in failed states and foreign tyrannies has been drained of its moral authority by events in Iraq and Afghanistan. Most terrorism analysts agree that the greater threat to our societies comes not from foreign regimes but home grown radicals. Terrorism cannot be stamped out by occupying armies on the other side of the world. Indeed, such foreign adventures merely make the threat to our societies greater by providing domestic fanatics with a steady stream of propaganda.

The front line, both in Britain and abroad, against terrorism is slowly becoming what it always should have been - a policing operation contingent on good intelligence. It is more important than ever that the police act with good judgement and sensitivity - for their conduct will largely determine our safety for the foreseeable future.