Al-Qaeda has made terrorism truly global, to deadly effect. But it may yet prove to be its own worst enemy...

Also in this special report:

A hydra-headed monster: Al-Qaeda may have been cut down in Afghanistan, but it is growing in Pakistan's border area. 

Hearts and minds: Al-Qaeda's star is falling in Iraq but rising in the Maghreb.

Doing their own thing: Unlike in America, terrorism in Europe is often homegrown.

Bending the rules: The high cost of Guantánamo Bay.

Powers of persuasion: Saudi Arabia tackles terrorism with a mixture of tough policing and gentle reeducation.

The self-destructive gene: Al-Qaeda's biggest weakness is its propensity to kill in discriminately.