``Global warming is now a weapon of mass destruction. It kills more people than terrorism, yet Blair and Bush do nothing.'' Houghton (2003)`N ow the invasion is upon us, surely we can delay no longer. We need to go at the task [of climate change] as though we are mobilising for war. In an unnecessarily great hurry.'' Leggett (2007) Imagining the worst The apocalypse looms ever nearer. Irreversible climate change, the threat of global terrorism, conflicts and wars over declining natural resources, the mobile avian flu carried by migratory birds, all resound to the fears prevalent in political and popular discourse in the 21st century (at least in the`developed world'). Whichever threat is conceived most pressing, there is a shortage of time in which to act, an immensity of tasks to accomplish, and the absolute necessity of taking precautionary action to prevent the very worst. The threats are both ultimately manageable with the relevant action, but also feared to be inherently unstable and potentially catastrophic, requiring precaution and investments in risk modelling. Managing the global future is legitimated under conditions of`extreme uncertainty' with these`total threats' that are, for Swyngedouw (2007), vague, ambiguous, but homogeneous. The presumed apocalyptic potential of contemporary threats thus underpins the call for precautionary, or preemptive, political action. The`precautionary principle' has become a central element of environmental politics, where it is increasingly accepted that regulatory action must be taken even if scientific evidence concerning the imminence and precise nature of threats remains disputed (Majone, 2002, page 90; Sunstein, 2003, pages 1005^1008). This principle, put simply, holds that``uncertainty is no excuse for inaction against serious or irreversible risks, [and] that absence of evidence
