ABSTRACT
For many years discussions have occurred amongst built environment professionals, urban managers and the agencies of security (especially the police) regarding the costs and benefits for urban authorities adopting counter-terrorism measures in the face of real or perceived terrorist threats. Some of the most historically explicit examples of such measures were seen in Northern Ireland in the early 1970s and 1980s where the military and urban planners used principles of ‘fortress urbanism’ to territorially control designated areas (Boal and Murray 1977; Boal 1995). This occurred most notably around the central shopping area in Belfast where access was barred, first, by concrete blockers and barbed wire, and then later by a series of high metal gates which became known as ‘the ring of steel’ (Brown 1985; Jarman 1993; Coaffee 2003). Subsequently this ‘ring of steel’ metaphor was reapplied in the 1990s to central London. The term has subsequently in more recent times been commonly used, almost ubiquitously, to describe any high profile security operation involving the sealing off of particular areas against the risk of terrorist attack.
