The Washington PostDemocracy Dies in Darkness

Urban terrorism isn’t going to stop. Can city planners help reduce its lethal impact?

As terrorists shift to soft targets and urban centers, can designers keep our cities safe and livable at the same time? (Agence France-Presse)

The van attack that killed one and left several injured near Finsbury Park mosque in north London last weekend is the latest in a sequence of high-profile, low-tech terrorist attacks in major urban areas. Before this latest incident, a van and knife assault on London Bridge and in nearby Borough Market on June 3 shocked leaders and citizens, a similar attack in Westminster killed five, and on July 14, 2016, a terrorist slaughtered 86 in Nice, France, by plowing through a pedestrian walkway in a large cargo truck. Across the Atlantic, a driver killed one and injured several by attempting to run down pedestrians in New York City’s Times Square last year, after which an Islamic State-affiliated media channel warned that there will be more vehicular attacks to come. To date, the Islamic State has produced guidance materials showing would-be terrorists how to kill with cars, trucks and knives.

But many cities aren’t ready for a new onslaught of urban terrorism. State security services have long been occupied with defending vulnerable urban spaces against attack, but until recently, the style of terrorist attack — the targeting of high-profile commercial or government buildings — seldom affected everyday city life. As we have seen from recent attacks, the modus operandi of terrorists has changed significantly in recent years and counter-responses, including urban planning, must adapt to this new reality.

Car and truck bombs targeting major financial or political centers (such as the Irish Republican Army bombing in London in the 1990s, and attacks in New York and Oklahoma City during that same decade) have been superseded by person-borne devices, especially suicide attacks; mass shootings; the deliberate targeting of crowds with vehicles; and knife attacks. From an urban planning perspective, this means that terror groups are increasingly aiming at soft targets and crowded places that cannot be altered without radically changing how we experience our cities. Is it possible, then, for planners to design out terrorism without upending how we use and feel about our urban centers?

It is, unfortunately, impossible to perfectly balance urban aesthetics and livability within secure design, just as it’s impossible to prevent every kind of attack in any open society. Still, there are important measures cities can take in their design plans to help avert this new breed of terrorist attack and to mitigate the damage done in the event they do take place, though design is no simple fix for halting all forms of urban terrorism.

Design interventions can be effective on two levels. First, they can limit access to vehicles seeking to attack public places. Designers primarily accomplish this by putting in place measures that seek to maximize the “standoff” distance between the road and target building or location. These security features, where possible, should be as unobtrusive as possible — in fact, some are already camouflaged and subtlety embedded within the cityscape. Examples of such “stealthy” features include balustrades or artwork erected as part of public realm improvements or hardened benches, lampposts or other streetscape elements that still provide a “hostile vehicle mitigation” functionality, with designs capable of stopping a seven-ton truck traveling at 50 miles per hour. In some cases, the use of specific types of trees can also be used in place of crash-rated bollards to provide protection.

Subtler design alterations can also reduce the speed of vehicles traveling to a target location. Small bends or turns in roads approaching crowded locations have often been used as a way to limit the speed at which a vehicle attack can be launched, hence reducing damage and loss of life. Invisible design interventions can also be put in place: For example, designers have advanced a modern-day version of a ‘tiger trap’ to limit the movement of vehicles in certain areas by way of collapsible paving the gives way under a certain weight.

Secondly, designers can create the visual impression that a place is under protection and impregnable to attack through the use of increasingly fortresslike design features notably bollards, gates and security cameras operating in conjunction with heavily armed and very visible policing. The downside of creating such a “safe zone” is that it can create an “architecture of paranoia” that people might be fearful to frequent. Rather than emitting feelings of safety and security, it foregrounds the possibility of attack, inducing a kind of securitized agoraphobia. Likewise, a heavily defended location might become a prime target for a terrorist attack, given the propaganda value that would be achieved if a terrorist managed to penetrate supposedly unassailable security.

Of course, if design elements are going to be effective, they should be accompanied by preparation for the event of their use. Preparedness activities can take a number of forms. Bespoke guidance has increasingly been issued by counterterrorism specialists to the owners and managers of crowded locations such as sports stadiums, bars and nightclubs, shopping centers and places of worship. Similarly, the responses to unorthodox terrorist attacks against a variety of crowded locations are regularly stress-tested through scenario role playing and live simulation exercises with emergency services and other stakeholders. To maximize the effectiveness of our cities’ built-in security features, municipal officials should continue to emphasize preparedness in the face of these shocking urban attacks.

Counterterrorism measures deployed in crowded public places must seek to balance security effectiveness with social and political acceptability. We live in dangerous times, but how we react to the risk of terrorism will have impact on our public realm for many years. Advancing proportionate security approaches where interventions are in line with risks is a difficult balancing act, but experience tells us that once permitted, hyper-security tends to become permanent. If we want a vibrant public realm and a genuinely open society, we should not let the exceptional become the norm as we seek more adaptable and effective ways of coping, in a calm and measured way, with urban terrorism.