Low Densities Are No Answer To The Threat Of Terrorism

The sprawling 1950's postwar urban pattern, once believed to provide a measure of security in the atomic age, has made us extremely vulnerable in an age of international terrorism.

By Michael Dudley

Michael DudleyThe world has changed forever, and the city has become a place of danger. The mere sound of an airplane overhead is now deeply unsettling. Where businesses once found downtown to be an attractive location, now many of them are considering relocating to distant suburban office parks. In response to widespread public fear, city planners and architects are seeking ways to address the threat posed by urban density.

Welcome to America, 1951.

The horrific mass murders of September 11th have resurrected the planning discourse of the early atomic era, and we are once again debating defensive dispersal, which at one time proposed that dispersed cities were less vulnerable to atomic explosions. Between 1945 and the mid-1950's, many of America's city planners and architects promoted low-density satellite towns, freeways and suburban industrialization as measures for survival in the nuclear age.

From a planning perspective, what has been singular about the events of the past month is how swiftly these arguments have reasserted themselves. Editorial writers in the popular and professional presses have predicted the end of both the "urban renaissance" and compact development, suggesting instead that further decentralization and automobility will thwart terrorists. Few probably recognize that these arguments are not new; but given the scale of the destruction wrought on September 11th, it is understandable that defensive dispersal has taken on new legitimacy. Yet fear, acted upon without reflection, will prevent us from asking the right questions.

The Cold War version of defensive dispersal was a tacit argument for learning to live with the bomb, rather than insisting upon its prohibition; its 21st Century counterpart would have us adjust our cities to the threat of terrorism without reference to its contexts. In both cases, there is a failure to recognize deeper connections.

The connections in this case come with an historical irony. Many of the plans that were once promoted in the name of national security are now familiar elements of the sprawling postwar urban pattern. Our cities now consume energy so spectacularly that the United States has become economically and militarily committed to the geopolitics of Persian Gulf oil. The instability of the region and the antipathies that have arisen from America's involvement there hardly need summarizing, but statements from al-Qaeda have been quite specific on the matter.

The irony is this: the dispersed city, which was once believed to provide a measure of security in the atomic age, has made us extremely vulnerable in an age of international terrorism.

Far from arguing against compact cities, the attacks on New York City and Washington should be telling us precisely the opposite. More compact and walkable communities can help us move towards a less petroleum-dependent economy, one in which America may no longer feel compelled to involve itself in--and exacerbate--the religious and ethnic conflicts in the Middle East. A new move to accelerate low-density development, by contrast, will only heighten our need for Persian Gulf oil (Alaskan stop-gap measures aside), and intensify the American diplomatic and military involvement that is so obviously resented there.

Defensive dispersal planners both then and now are correct about one thing: the shape of the city has national security implications -- just not in the way these planners believe. While it would be both absurd and monstrous to lay blame for the tragedy of September 11th on urban sprawl, it is not too much to say that planning compact and self-sufficient cities could make significant contributions towards a more stable, equitable--and therefore more secure--world.

Michael Dudley is a Senior Research Associate and Librarian with the Institute of Urban Studies in Winnipeg, Manitoba. His article, "Sprawl as Strategy: City Planners Face the Bomb" was published in the September issue of The Journal of Planning Education and Research.




Your site was forwarded to me by a colleague, John C. Henry, AIA and I applaud your efforts, if only partially. Over the weekend, I met with other colleagues and Andres Duany at Seaside, and I think that he would also accept your intuitiveness, taking it in a parallel but alternate course. To me, high density does not mean going vertical. It is that vertical mentality of urban architecture that has put major cities in the cross hairs of terrorists. For more insight, please read my 1988 editorial and post 9/11 addendum at www.aibd.org and click on the public forum.

3rd Path

High or low density settlements cannot be a solution since there is not enough time or money to significantly rebuild our metropolitan areas as a strategy for safety, or as an energy conservation strategy. I have developed a 3rd path that can address both safety and energy conservation by retrofitting metro areas with digital networks and public, mixed-use network access centers. I refer to this as Network Oriented Development. This strategy was awarded first prize in the "Millennium City" category of a livable communities design competition held earlier this year by the Orange County Council of Governments in California. Total deployment of this strategy can occur in any metro area in less than 5 years.

Sense of logic

It's surprising to see the general term "density" still bandied about as legitimate. Both high and low density development have the similar effect of creating a transportation demand, (to travel between purposeful destinations). The more useful term is "mixed-use", please! Manhattan is not mixed-use. Suburban sudivisions are not mixed-use. These two, isolationist development types have a transportation demand that can never be met.

Dudley's use of the term "decentralization" also has a tortured meaning. Sprawling subdivisions do not have sufficient centralized structure to challenge the "centralization" located in central cities. Sprawl strengthes city center centralization, if it continues the pattern of single-purpose housing isolated from corporate office park isolated from commercial strip mall, etc.

In order to maintain my personal sense of logic, I must label the 911 disaster at the WTC and at the Pentagon as a rejection of enforced globalization, not religious or cultural differences. It would be wise to discuss globalization and its many fatal flaws, inequities, costs and impacts as an inanimate target worthy for all sides to place blame. Globalization is NOT sustainable. It is the root cause of traffic congestion, the high cost of living and much racial tension. As mixed-use development displaces isolationist development, local economies become strong enough to refuse the global economy as well as function independently of Middle East petroleum.

High densities, but not superhigh

I agree with Mr. Dudley wholeheartedly. I'd also like to add that the kind of density that composed the WTC was excessive. I don't know that anyone who considers her- or himself to be an environmentally conscious, civic-minded advocate of dense development would laud the sort of inhuman density of the WTC. A middle ground makes much more sense--where the tepid monotony of the single-family-home suburbs is not refuted with 100-story megatowers but with 4-story clustered residential buildings, narrower streets with less car traffic, businesses more or less integrated with residential areas instead of marooned in sky-high business districts. This vision of density hardly seems to possess the symbolic attraction that something as larger-than-life as the WTC possessed. While it's true that denser areas would allow for a swifter spread of biological agents, who wants to live life cowering alone in a bunker?

Density of the sort I'm describing eliminates the oil dependence of sprawl as well as the security problems and symbolic pull of buildings of superhuman scale. Sure, it's not 100% safe, but what the heck is? Anything that is worth doing takes courage--the planning of humanely dense, life-affirming communities included.


Disagree - Dispersal is the safest form of urbanism

I am an urbanist. I am an environmentalist. I want as much as all of you for America to change its ways, to be more more "urban" and ecological. But the fact of the matter is that the terrorists will target and most likely succeed in destroying high density locals.

Dispersal is in the fact the safest form of urbanism in the threat of nuclear attack. However, it is highly unlikely that we will experience a nuclear attack, and even if we do, does this discussion really even matter?! Sure, more people would survive initially, but our cities would fall into chaos and very few people would survive ultimately.

Given that Americans now have a new perception anyway, I don't expect to see much action taken to re-urbanize our cities.

Low Densities

While Mr. Dudley's surface argument certainly has merit -- that urbanity's efficiencies can improve our country's energy independence -- the core of the issue is simply another call for "sustainability." This light should (and likely will) be used in the re-examination of skyscrapers in general; as Kunstler and others have already argued, neither intensely concentrated (skyscrapers) nor diffuse (sprawl) architypes best serve our social, economic, or environmental needs. September 11th grimly illustrates that these conditions apply to our safety/defensive needs, as well.

Vulnerability to oil supply shortage

While the compact city concept is attractive to some extent, I think it is a fantasy in terms of how long it would take to accomplish - given that something like 160 million people now live in "suburbs" in the U.S. I think a major effort (crash program)is needed to find alternative sources of energy right now as our vulnerability to a significant reduction in oil is very great. We can and should do this right now while making what adjustments are possible, in both suburban and central city areas, to increasing density. But, we should realize that this is a very long term solution and we don't have much time to deal effectively with this problem.

Do not agree

While atomic bombs may not fly (heaven forbid), the current terrorist threat appears to come from within (unlike the '50s) and to strike at high density targets. Dispersal makes the best sense if terrorists will continue to operate as they did on 9/11. Yes, if we did not depend on so much foreigh oil, we might not be in this predicament. If oil revenues in terrorist supported states are funding these acts, and we can stop importing it, then theoretically the terrorism would subside. But the 9/11 attacks could be funded for very little money ($200,000 estimate) that can be raised by other means. Besides, the rest of the industrialized world depends on foreign oi. There is no way the first world consumers can alter energy use patterns fast enough to make any dent in these types of attacks. If the terrorists follow the Palestinian model, then there will be suicide bombers walking up to any congested area, including an office building, shopping mall, bus stop, etc. A super suburbia that communicates via electronic means, that receives delivery of goods by retail to consumer trucking and the mail, etc. would be the best defense. For a more elaborate scenario, see "If Terror Succeeds", at http://www.designarchitecture.com/view_article.cfm?aid=398&return=articl...



Thanks for your comments. I could not agree more. I would also add that the best long-term defense against terrorism is to have an open society where we encounter human beings in public spaces, rather than a gated society in which people are anonymous "others" behind walls and enclosed metal boxes.


You illustrated perfectly that more than ever Americans need to embrace urbanism. We need to embrace walking, biking and transit as an American patriotic duty. Our people can not be afraid to operate in our strongest and most effective places, DOWNTOWNS! I would like to add that the only positive attribute of the Sept. 11th tragedy is that this country may rethink it's reliance on air travel. With correct leadership this tragedy could catalize a rail revolution. Thus reducing our need for foriegn oil and returning our neighborhoods.


I really liked the way you linked the present discourse with the one from the fifties. I also appreciated your concise discussion of the alternative discourse about cities that needs to occur. I read in the Globe and Mail this morning that Americans, at 5% of the world's population consumes 10% of the daily oil supplies via cars and SUVs. Your argument is certainly supported by these statistics! Bravo re: your editorial!

Low Density Editorial

Bravo! Mr. Dudley is totally correct. One of the biggest reasons we are in this mess is because of America's dependence on oil from an unstable and repressive part of the world. We have sacrificed our national values and ideals for half a century in order to reap the "benefits" of "cheap" oil from repressive and ugly governments in this area of the world. Now we see the real cost of these relationships, which we should have acknowledged years ago. As long as we are hogtied to the Saudis and company, we will continue to be drawn into their medieval dramas. Thank you Mr. Dudley

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