On 20 September 2001, in an address to a Joint Session of Congress and the American people, President George W Bush declared a 'war on terror'. The concept of the 'war on terror' has proven to be both an attractive and a potent rhetorical device. It has been adopted and elaborated upon by political leaders around the world, particularly in the context of military action in Afghanistan and Iraq. But use of the rhetoric has not been confined to the...