Safety and Security Engineering 805 Architecture in the era of terror: the security dilemma G. Zilbershtein Department of Architecture, Texas A&M University, U.S.A. Abstract The growing public concern over the proliferation of terrorism has made protection of the physical environment of potential targets and terror interdiction a salient issue. The objective to secure the built environment against terrorism introduces a complex dilemma. At one level, the extent of investments in security in terms of cost-effectiveness is not proportional to the relatively rare threat of terrorism. Another level of the dilemma is rooted in the complex psychological implications of using security measures, that is, how to physically secure a building, while psychologically deter potential terrorists; more importantly is the question of how to accomplish those and yet not scare the users, i.e., the public. The latter part of the dilemma has been relatively ignored in the analysis of architectural measures against terrorism. And since catering to the psychological comfort of the users of the built environment has always been one of the greatest challenges of architecture, this paper focuses on that portion of the security dilemma of terrorism. Specifically, the study examines the threat characteristics and analyzes design recommendations that address the threat of terror for their contribution to the psychological comfort of the end users. Keywords: architecture, built environment, terrorism, risk assessment, security perception, security measures, design recommendations. 1 Introduction The post–cold war, as defined by John Lewis Gaddis [1], began with the collapse of one structure, the Berlin wall on November 9, 1989, and ended with the collapse of another, the World Trade Center on September 11, 2001. Paul Bracken [2] describes this new age as the era of “think the unthinkable”, as it has become a common term in thinking of our life in a terror stricken environment. WIT Transactions on The Built Environment, Vol 82, © 2005 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) 806 Safety and Security Engineering How far should society, and designers of environments, take this slogan? How do we assess the risks and accommodate our design approach to it, when the entire concept of buildings as our shelters is questioned? How can design deal/work against the physical and the psychological threats of terror? Launching the discussion, we need to consider what terrorism is, and what measures are taken to counter this threat. While there is no single, universally accepted, definition to terrorism and whether it is perceived as a righteous fight for a higher cause, or as an unlawful horrible act, according to all, it is associated with the “use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof” [3]. Counter-terrorism includes operations on different levels. Central to this paper that focuses on the built environment as it relates to the threat of terror, are efforts to secure potential targets and threat interdiction. These correspond to one of the greatest challenges of the design realm: to provide the users of the built environment with physically and psychologically comfortable designs [6, 7, 8]. The two aspects of comfort are inherently associated with security [8]. Consequently, this paper provides a first step towards a better understanding of the nexus: terrorism threat - physical environment - users of the environment. This is accomplished through a rational assessment of risks; and a review of existing counter-terrorism design policies/measures to physically secure a place, while analysing their relevance to the psychological comfort of the end users. 2 Assessing the risk 2.1 General Fulfilling the architecture profession’s objective to protect people and property from various offenses requires a development of an introspective definition of specific security needs. Many sources refer to the analysis by which security needs are defined as a risk assessment. Risk assessment examines the consequences of hostile actions for a building and its occupants. It consists of: (1) threat analysis which defines the level of threat to a facility by evaluating the intent, motivation, and possible tactics of potential offenders; (2) asset analysis that identifies and prioritizes the asset to be protected according to its nature, value, location and how, when, and by whom it is accessed and used; (3) vulnerability analysis which defines the weaknesses of a facility in its design, construction, operation and location [9]. Over the years, computer applications have been integrated into the risk assessment analysis (e.g., CAPIndex). Such applications calculate probability assessment as related to statistics of specific categories of crime, based on location and use of the architectural item [10]. 2.2 The risk of terrorism In the case of terrorism, assessment of risk is an intricate matter. While it seems that the media covers terror attacks around the globe on a daily basis, the actual number of occurrences is too limited to reach a significant numerical probability WIT Transactions on The Built Environment, Vol 82, © 2005 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) Safety and Security Engineering 807 for a place [10]. Inevitably, current statistics of terrorism patterns are only supporters to theoretical risk assessment endeavors. A theoretical testing of the three basic components of terrorism risk assessment is presented. 2.2.1 Threat analysis Many sources present different views on terrorists’ motivation. It is not for this paper to speculate or judge whether terrorism is means to an end, utilized for achieving other political, social or religious goals [5], or whether it has become “the end in itself” [3]. The discussion however, does point out two main issues. First, as recognized by many around the world, terrorism is associated with fear or instigation of it. Empirical evidence attests that terrorism is one of the most dreaded man-made hazards [11]. Second, the lethality of terrorism attacks has grown. Statistics from the last 20 years show that while the number of attacks decreased over the years, they have become more lethal [4, 12]. Terrorism can be manifested in different forms: assassination, armed assault, hijacking, hostage-taking, bombings, product or air contamination and cyber- terrorism [5, 12]. Many of these involve the incursion of armed terrorists into a target. Most common terrorism acts are bombings [13]. These involve the use of explosives that are relatively easy to obtain, or by utilizing whatever destructive means are available as incendiary devices (e.g., using airplanes as missiles in September 11) [13, 14]. Besides being destructive, and relatively easy to carry through, bombing events also appeal to terrorists due to their theatrical nature. The extensive media coverage of events with bleeding casualties and severely damaged environments serves two interrelated purposes: demonstrating power over authorities and inducing fear in the population [14]. Despite of past tendencies to use conventional weapons [12], the risks of chemical, biological, radiological or nuclear (CBRN) attacks are not to be dismissed [4, 14]. Multiple simultaneous attacks or sequential attacks in a concentrated area also need to be addressed. Another factor to consider is the growing number of suicide missions [12, 14]. This may have an impact on tactics of defense in the built environment. Theories such as defensible space, Crime Prevention through Environmental Design, CPTED [15, 16, 17], were developed to address threats of conventional crime. These theories, which rely on deterrence by raising the probability of perpetrator to be caught in action, need to be re-evaluated as terrorists may not fear death. Moreover, even if terrorists are prevented from reaching their ultimate target, the space where they are stopped may suffer the hit. 2.2.2 Asset analysis It is almost impossible to develop a comprehensive list of potential terrorism targets, as in today’s urban environment target selection is nearly unlimited. Yet, the presumed intention of terrorism to maximize destruction suggests traits of possible targets: facilities which possess symbolic value, those that if damaged would provoke anxiety/fear among the population, would disturb the economy, or infrastructure; and those which offer the possibility of a Mass Casualty Incident – MCI [5, 18, 19]. Using September 11 terrorist attacks in the US as a case study, we find that the target fits most of these traits: devastating damage to the physical environment and to human lives in a place of symbolic and WIT Transactions on The Built Environment, Vol 82, © 2005 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) 808 Safety and Security Engineering economic significance. However, sources contend that despite that attack fear does not dominate Americans’ lives -- people feel comfortable and safe enough to continue everyday activities without much consideration of possible terrorist attacks [20]. The terrorists’ failure in that respect may suggest that in the future, terrorist organizations will attempt to hit places where every American may happen to be during daily activities. The latter assumption is supported by what has been the case in other parts of the world (e.g., in Europe, in the Middle East). Consequently, most probable future targets are places which present opportunity of MCI and great destruction