assume that terrorists and 'rogue states' are more naturally inclined to use such weapons, turning the imagined terrorist into a kind of Godzilla, with an unrivalled capacity to tear whole cities to shreds.

If these powers are terrifying, they are also useful. In the post 9/11 world, catastrophic scenarios generate a sense of unbearable urgency, in which, like Kiefer Sutherland's torturing hero, the world has only 24 hours - or 45 minutes - to stave off disaster. Such urgency tends to generate draconian anti-terror legislation, states of emergency and war, rather than sober analysis.

The 9/11 atrocities - and the still unsolved anthrax attacks that accompanied them - were used with jaw-dropping cynicism to mobilise support for the Iraq war. Today the clock is ticking once again, as hawkish politicians warn of the horrors awaiting the world if a 'terrorist-sponsoring state' like Iran gets the bomb and openly express an unhealthy yearning for 'another calamity' to galvanise support for a new war.

No one can deny the possibility of a future

atrocity on the scale of 9/11 or even greater, but such fears need to be put in perspective. It is worth remembering that the 'anarchist terror' was largely eclipsed by the carnage of World War I - a catastrophe from within civilisation, not from the 'mad dogs' outside it.

In today's perfect storm of rampant militarism, resource wars, rising food prices and ecological degradation, there are many potential disasters looming on the horizon apart from the terrorist with the dirty bomb in the suitcase, from the prospect of a major conflict in the Middle East to mass starvation. To prevent these catastrophes will require a similar level of urgency.

Instead of imagining a future of endless murder and mayhem like the junkie painter in Heroes, we might do better to look for ways to bring more hope and less fear into this beleaguered planet. And instead of cowering under the covers from the terrorists in the cupboard, we might take consolation from Gertrude Stein's observation that "everything is so dangerous that nothing is really very frightening".