The rise of Al Qaeda has been that of a uniquely powerful new breed of violent non-state actors, bringing terrorism to an unprecedented level of destruction. But Al Qaeda’s strength has been fading, thanks to the efforts of counter-terrorism but no less because of its strategic limitations. However, there is no reason to expect terrorist violence from dying down. The advent of massively destructive terrorism is a direct consequence of the empowerment of non-state actors flowing from the ongoing processes of globalization. The means of disruption and destruction will continue to become increasingly available. To discern the face of post-Al Qaeda terrorism, one must not only look at the existing groups of Jihadi terrorists of the sort which committed the “7/7” bombing in London in 2005 or the more recent attacks in Algeria. The future of the terrorist challenge may be found in cases such as the chemical and biological “exploits” of the Aum cult in Japan in the mid-nineties or the perpetrator of the anthrax attacks in the US in the autumn of 2001. A successful counter-terrorism strategy must be based on the twin assumptions of higher levels of potential destruction and of a more varied, more dispersed set of terrorist actors equipped with chemical, biological or radiological weapons.