Will Great Cities Survive?

For the first time in human history, a majority of the earth's population lives in cities. But though great cities have been among humanity's supreme achievements down through the ages, they now face an uncertain future, threatened by forces that could undermine the very things that have made them great.

On November 8, 1519, Bernal Dfaz del Castillo saw a sight that would stay with him forever. Serving under Hernando Cortes, the 27-year-old Spanish soldier had already encountered signs of urban civilization that multiplied as he and his comrades marched from the humid lowlands of Mexico up into the volcanic highlands. (In a hint of what was to come, he noted "piles of human skulls" arranged in neat rows atop the provincial temples.) Then, suddenly, a city of almost unimaginable scale appeared, built high in the mountains on a lake crowned by a circle of volcanic peaks. Dfaz beheld broad causeways filled with canoes, avenues where every kind of produce, fowl, and utensil was being sold, elaborate flower-decked homes, large palaces, and temples rising bright in the Mexican sun:

Gazing on such wonderful sights, we did not know what to do or say, or whether what appeared before us was real, for on one side, on the land, were great cities; and in the lake ever so many more, and the lake itself was crowded with canoes, and in the Causeway were many bridges at intervals, and in front of us stood the great City of Mexico.

The sights Dfaz saw that November day were such as have always inspired human beings encountering great cities. His was the reaction of a Semitic nomad in the presence of the walls and pyramids of Sumer 5,000 years earlier, or a Chinese provincial official entering Loyang in the seventh century B.C., or a Muslim pilgrim arriving by caravan at the gates of ninth-century Baghdad, or an Italian immigrant in the early 20th century spying the awesome towers of New York from the deck of a steamer.

Cities are humanity's greatest creation. They represent the ultimate handiwork of our imagination as a species and testify to our ability to reshape the natural environment in profound and lasting ways. Cities compress and unleash the creative urges of humanity. They are the places that, over the course of five to seven millennia, have generated most of our art, religion, culture, commerce, and technology.

Some cities started as little more than clusters of villages, which over time grew together and developed mass. Others have reflected the vision of a high priest, ruler, or business elite following a general plan to fulfill some great divine, political, or economic purpose. Cities have been built in virtually every part of the world, from the highlands of Peru to the tip of southern Africa and the coasts of Australia. The oldest permanent urban footprints are believed to be in Mesopotamia, the land between the Tigris and Euphrates rivers. The founding experiences of the Western urban heritage occurred there and in a plethora of subsequent metropolises -- including Ur, Agade, Babylon, Nineveh, Memphis, Knossos, and Tyre. Many other cities sprang up independently of these early Mesopotamian and Mediterranean settlements, and some of them, such as Mohenjo Daro and Harappa in Pakistan, and Chang'an in China, achieved a scale and complexity equal to that of any of their Western contemporaries. Indeed, for many centuries after the fall of Rome, these "Oriental" capitals were among the most advanced and complex urban systems on the planet. Urbanism must be approached not as a largely Western phenomenon but as one that has worn many different guises reflective of some greater universal human aspiration.

The primary locus of world-shaping cities in each region of the globe has shifted over and over again, and the often rapid rise and fall of great cities was already familiar to the Greek historian Herodotus in the fifth century B.C.:

For most of those which were great once are small today. And those that used to be small were great in my own time. Knowing, therefore, that human prosperity never abides long in the same place, I shall pay attention to both alike.

By Herodotus's time, some of the greatest and most populous cities of the past (Ur, Nineveh) had declined to insignificance, leaving little more than the dried bones of what had once been thriving urban organisms. Babylon, Athens, and Syracuse were then in their glorious prime; within a few centuries, they would be supplanted by Rome and Alexandria.

What makes cities great, and what causes their gradual demise? I believe that three critical factors above all have determined the overall health of cities: the sacredness of place, the ability to provide security and project power, and the animating role of commerce. When these factors are present, urban culture flourishes; when they weaken, cities decline.

Religious structures -- temples, cathedrals, mosques, pyramids -- have long dominated the landscape of great cities. These buildings once marked the city as a sacred place, connected directly to divine forces controlling the world. In our secularly oriented times, cities seek to recreate the sense of sacred place through towering commercial buildings and evocative cultural structures that inspire a sense of civic patriotism or awe, without the comforting suggestion of divine guidance.

Defensive systems have also played a critical role in the ascendancy of cities, which, first and foremost, must be safe. Many cities, observed the historian Henri Pirenne, first arose as places of refuge from marauding nomads, or from the general lawlessness that has beset large portions of the globe throughout history. When a city's ability to guarantee safety declines, as occurred in the last years of the western half of the Roman Empire, or during the crime-infested last decades of the 20th century, urbanites migrate to a safer urban bastion -- or retreat to the hinterlands.

Yet sanctity and safety alone cannot create great cities. Priests, soldiers, and bureaucrats may provide the prerequisites for urban success, but they themselves cannot produce enough wealth to sustain a large population for a long period of time. That requires an active economy of artisans, merchants, working people, and, sadly, in many places throughout history, slaves. Since the advent of capitalism, these disparate groups, necessarily the vast majority of urbanites, have emerged as the primary creators of the city.

To be successful today, urban areas must resonate with the ancient fundamentals -- they must be sacred, safe, and busy. What was true 5,000 years ago, when cities housed a tiny portion of humanity, is still true in this century, the first in which a majority of the earth's population are urban dwellers. The world's urban population was only 750 million in 1960, grew to three billion by 2002, and is expected to surpass five billion in 2030. These swelling ranks face a vastly changed environment, in which the most powerful urban area must compete not only with other large places, but also with an ever wider array of smaller cities, suburbs, and towns.

In the past, size allowed cities to dominate the economies of their hinterlands. Today, the very girth of the most populous megacities -- Mexico City, Cairo, Lagos, Mumbai, Kolkata, Spo Paulo, Jakarta, Manila -- is often more a burden than an advantage. In some places, these urban giants have been losing out to smaller, better-managed, less socially beleaguered settlements. In East Asia, for example, the critical nursery of 21st-century urbanism, Singapore, has integrated itself into the global economy more successfully than the far more populous Bangkok, Jakarta, and Manila.

In the Middle East, megacities like Cairo and Tehran have suffered trying to keep pace with their exploding populations, while smaller, more compact centers such as Dubai and Abu Dhabi have flourished. Dubai, a dusty settlement of 25,000 in 1948, saw its population approach one million by the end of the century, yet it has avoided the economic stagnation that afflicts most of the Arab world. Cosmopolitan attitudes, such as those in Dubai, continue to have a major impact in determining the success of cities. In the past, openness to varied cultures and the clever employment of talent helped relatively small cities such as Tyre, Florence, and Amsterdam play outsize roles. Similarly, in the 21st century, a small cosmopolitan city such as Luxembourg, Singapore, or Tel Aviv often wields more economic influence than a sprawling megacity.

As the 20th century drew to a close, megacities in the advanced countries seemed to be enjoying brighter economic prospects. There was a statistically small but notable increase in residential development in some long-abandoned downtowns. Many observers asserted that the most cosmopolitan "world cities" -- London, New York, Chicago, Tokyo, and San Francisco -- had indeed irrevocably "turned the corner." "Neither Western civilization nor Western cities," remarked the historian Peter Hall, "show any sign of decay." This new optimism rested largely on the impact of global integration and the worldwide shift from a manufacturing-based to an information-based economy.

But the upbeat assessment may be replacing the excessive pessimism of the 1960s with a magnified sense of optimism. Even the most evolved "global cities" now find the advantages of scale diminished by the rise of new technologies that, in the words of the anthropologist Robert McC. Adams, have accomplished "an awesome technological destruction of distance." The ability to process and transmit information globally, and across great expanses, undermines many traditional advantages enjoyed by established urban centers. Throughout the last third of the 20th century, secular trends, particularly in the United States, pointed to a continued shift of corporate headquarters to the suburbs and smaller cities. In 1969, only 11 percent of America's largest companies were headquartered in the suburbs; a quarter-century later, roughly half had migrated to the city periphery.

In fact, high-end services, the supposed linchpin of "global city" economics, have continued to disperse toward the periphery or to smaller cities. This trend is even more marked among firms in the largest generator of new growth, the entrepreneurial sector. Improvements in telecommunications promise to further flatten economic space in the future, with choice jobs able to migrate to exurbs and small cities. One result has been a shift in the very landscape of growth, with suburban office parks widely favored over gleaming high-rise towers. The global securities industry, once overwhelmingly concentrated in the financial districts of London and New York, has gradually transferred an ever larger share of its operations to the cities' respective suburban rings, to other smaller cities, and overseas. The company headquarters may remain in a midtown high-rise, but more and more of the jobs are located elsewhere.

These decentralizing trends have taken an unmistakable toll on the overall economic relevance of New York, still the most important of the advanced world's megacities. In the last three decades of the 20th century -- a period of explosive job growth across the United States -- the city's private sector created virtually no new net employment. A powerful service economy remained, but as the historian Fred Siegel pointed out, the long-term trends showed the city slipping further behind the nation "with each new turn of the cycle."

And in a country as highly centralized as Japan, software companies and other technology-centered enterprises have begun to move away from the great centers of Osaka and Tokyo to outlying prefectures. Hong Kong, too, has hemorrhaged both high-tech manufacturing and engineering positions to surrounding parts of mainland China. The rise of "telecities" around the world suggests the emergence of new high-end industrial pockets, such as those in the less urbanized sections of France, Belgium, and South Korea. And the increase in telecommuting threatens to reduce still further the roles once played exclusively by urban regions.

Even the best-positioned urban area, then, will have to deal with severe demographic and economic challenges. Many of the young people lured to these cities in their twenties often depart when they start families and businesses; upwardly mobile immigrants, critical contributors to the urban resurgence, increasingly join the exodus. European, Japanese, and other East Asian urban centers confront a yet more extreme demographic crisis: Low birthrates are reducing the ranks of young people, the group most attracted to large cities, and choking off the traditional pool of immigrants from the countryside.

With economic growth shifting elsewhere, many leading cities in the advanced world are resting their hopes for the future on their role as centers of culture and entertainment. These cities may be fulfilling the prediction H.G. Wells made a century ago, when he said that the city would move from a commanding position at the center of economic life toward a more ephemeral role as a "bazaar, a great gallery of shops and [place] of concourse and rendezvous." Cities have played this staging role since their origins. Central squares, the areas around temples, cathedrals, and mosques, long provided ideal places for merchants to sell their wares. Being natural theaters, cities offered the overwhelmingly rural populations around them a host of novel experiences unavailable in the hinterlands. Rome, the first megacity, developed these functions to an unprecedented level. It boasted both the first giant shopping mall, the multistory Mercatus Traiani, and the Colosseum, a place where urban entertainment grew monstrous in its size and nature.

In the industrial era, observed the French philosopher Jacques Ellul, "the techniques of amusement" became "more indispensable to make urban suffering bearable." By the 20th century, industrialized mass entertainment -- publishing, motion pictures, radio, and television -- was exerting an ever stronger hold on the life of urban dwellers. Media-related businesses also accounted for a growing part of the economy in such key image-producing cities as Los Angeles, York, Paris, London, Hong Kong, Tokyo, and Mumbai. By the early 21st century, the focus on cultural industries began to inform economic policy in many urban areas. Instead of working to retain middle-class families and factory jobs or to engage in economic competition with the periphery, urban regions embraced such fleeting qualities as fashionability, hipness, trendiness, and style as the keys to their survival.

In Rome, Paris, San Francisco, Miami, Montreal, and New York, tourism now ranks among the largest and most promising industries. The economies of some of the fastest-growing centers, such as Las Vegas and Orlando, rely heavily on the staging of "experiences," complete with eye-catching architecture and round-the-clock live entertainment. Indeed, in such unlikely places as Manchester, Montreal, and Detroit, political and business leaders hope that by creating "cool cities" they may lure gays, bohemians, and young "creatives" to their towns. In some places, the accoutrements of this kind of growth -- loft developments, good restaurants, clubs, unique shops, museums, galleries, and sizable gay and single populations -- have succeeded in reviving once-desolate town centers. But they have not succeeded in restoring anything remotely reminiscent of these cities' past economic dynamism.

In the 21st century, some cities or parts of cities may survive, and perhaps thrive, on a transitory foundation, and, with the support of their still-dominant media industries, they may successfully market to the world the notion that they represent the future. The brief but widely acclaimed rise of urban technology districts -- such as New York's Silicon Alley and San Francisco's Multimedia Gulch -- during the dotcom boom of the late 1990s led some to identify hipness and urban edginess as the primary catalysts for information-age growth. Both districts ultimately shriveled as the Internet industry contracted and then matured, yet the market for new housing continued to grow. This demand came partly from younger professionals, but also from a growing population of older affluent individuals, including those hoping to experience a more "pluralistic" way of life. These modern-day nomads often reside part-time in cites, either to participate in their cultural life or to transact critical business. In some cities -- Paris, for example -- they constitute, by one estimate, 10 percent of the population.

The rush in many "global cities" to convert old warehouses, factories, and office buildings into elegant residences suggests the gradual transformation of former urban economic centers into residential resorts. The declining old financial district of lower Manhattan, the architectural historian Robert Bruegmann has noted, seems likely to revive not as a technology hub but as a full- or part-time home for "wealthy cosmopolites wishing to enjoy urban amenities in the elegantly recycled shell of a former business center."

Over time, however, this culturally based growth may not be self-sustaining. In the past, achievement in the arts flourished in the wake of economic or political dynamism. Athens first emerged as a bustling mercantile center and military power before it astonished the world in other fields. The extraordinary cultural production of other great cities, from Alexandria and Kaifeng to Venice, Amsterdam, London, and, in the 20th century, New York, rested upon a similar nexus between the aesthetic and the mundane.

Broad demographic trends do not bode well for cities basing their futures on cultural growth. The decline in the urban middle-class family-a pattern previously seen in both the late Roman Empire and 18th-century Venice -- deprives urban areas of a critical source of economic and social vitality. In Japan and Europe, the number of young workers is already dropping. Super-annuated Japanese cities face increasing difficulties competing with their Chinese counterparts, which are being enriched by the migration of ambitious young families from China's vast agricultural hinterlands. It is hard to imagine the continued preeminence of Japan in Asian popular culture if its population of young people keeps shrinking. Over time, the economically ascendant cities of the world -- Houston, Dallas, Phoenix, Shanghai, Beijing, Mumbai, and Bangalore -- seem certain to generate their own aesthetically based industries.

Finally, the "ephemeral" city seems likely to encounter profound social conflicts. An economy oriented to entertainment, tourism, and "creative" functions is ill suited to provide upward mobility for more than a small slice of a city's population. Focused largely on boosting culture and constructing spectacular buildings, urban governments may tend to neglect more mundane industries, basic education, and infrastructure. Following such a course, urban areas are likely to evolve into "dual cities," made up of a cosmopolitan elite and a large class of those who, usually for low wages, serve the elite's needs.

To avoid these pitfalls, cities must emphasize those basic elements long critical to the making of vital commercial places. A busy city must be more than a construct of diversions for essentially nomadic populations. It requires an engaged and committed citizenry with a long-term financial and familial stake in the metropolis. A successful city must be home not only to museums, restaurants, and edgy clubs but to specialized industries, small businesses, schools, and neighborhoods capable of renewing themselves for the next generation.

Successful cities flourish under law and order, and maintaining a strong security regime can do much to revive an urban area. One critical element in the late-20th-century revival in some American cities, most notably New York, was a significant drop in crime, accomplished by the adoption of new policing methods and a widespread determination to make public safety the number one priority of government. Indeed, the 1990s represented arguably the greatest epoch of crime reduction in American history, providing a critical precondition for the growth of tourism and a modest demographic rebound in some major cities. Even Los Angeles, after the devastating riots of 1992, managed to curtail crime and stage an economic and demographic recovery.

But as security in American cities improved, new threats to the urban future surfaced in the developing world. By the end of the 20th century, crime in megacities such as Rio de Janeiro and Spo Paulo had devolved into what one law enforcement official called "urban guerrilla war." Drug trafficking, gangs, and general lawlessness also infest many parts of Mexico City, Tijuana, and San Salvador. Inevitably, the erosion of basic security undermines city life. Capricious authority and fear of crime can divert the movement of foreign capital as well, toward safer locations in the suburban periphery.

Insidious, too, are the effects of pollution and growing health-related problems in many cities of the developing world. At least 600 million city residents worldwide lack access to basic sanitation and medical care. These populations become natural breeding grounds for deadly infectious diseases, against which neither affluence nor foreign nationality necessarily provides immunity. Such threats drive both indigenous professionals and foreign investors to more healthful environments abroad, or to secure suburbs.

The Islamic Middle East, where the familiar woes of developing countries have been exacerbated by enormous social and political dislocations, poses the most immediate danger to the security of cities globally. In trying to adopt Western models of city building during the 20th century, many Islamic cities weakened traditional bonds of community and neighborhood but failed to replace them with modern and socially sustainable alternatives. This transformation, according to the historian Stefano Bianca, "sapped the shaping forces of cultural identity," leaving behind a population alienated from its increasingly Westernized environment. The alienation has been deepened by political conflicts, the most important of which is the struggle with an economically and militarily advanced Israel. The aspirations of Islamic, and particularly Arab, cities are continually thwarted not only by economic, social, and environmental failures but also by repeated humiliations on the battlefield.

To a large extent, Islamic societies have also failed to adjust to the cosmopolitan standards necessary to compete in the global economy. Beirut, the Arab city best positioned for cosmopolitan success, foundered because of incessant civil strife, and did not make an serious efforts to rebuild itself until the late 1990s. Other potentially successful Islamic cities, such as Tehran and Cairo, still lack the social stability and transparent legal systems that are critical to attracting overseas investors. Even the best-run of the Islamic countries, such as the United Arab Emirates, still suffer from political and legal systems far more arbitrary than those in the West, or in the Asian states that are home to great cities such as Singapore, Taipei, Seoul, and Tokyo.

From the difficult milieu of the Middle East has emerged perhaps the greatest menace to the future of modern cities -- Islamist terrorism. Islamist terrorists regard the West, particularly its great cities, as intrinsically evil, exploitative, and un-Islamic. One Arab scholar has labeled the leaders of the Islamist movement "angry sons of a failed generation," who saw the secularist dream of Arab unity dissolve into corruption, poverty, and social chaos. For the most part, their anger was incubated not in the deserts or small villages but in such major Islamic cities as Cairo, Jeddah, Beirut, and Kuwait. Some were longtime residents of New York, London, or Hamburg, and that experience abroad seems only to have deepened their anger toward the West and its cities. As early as 1990, one terrorist, an Egyptian living in New York, spoke of "destroying the pillars such as their touristic infrastructure which they are proud of and their high world buildings that they are proud of." Eleven years later, that anger shook the urban world to its very foundation. In addition to the economic and social afflictions that beset them, cities now have to contend with the prospect of physical obliteration.

The current threat to the prosperity and survival of cities presented by loosely affiliated marauders instead of states has its historical analogues. Some of the worst damage done to cities in the past was inflicted by nomadic peoples and small bands of brigands. But despite setbacks, the urban ideal has demonstrated a remarkable resilience. Fear rarely is enough to stop the determined builders of cities. For all the cities that have been ruined permanently by war, pestilence, or natural disaster, many others have been rebuilt, often more than once. Indeed, amid mounting terrorist threats, officials and developers in cities such as New York, London, Tokyo, and Shanghai continue to plan new office towers and other striking edifices.

But far more important than the construction of new buildings to the future of cities will be the value people place on the urban experience. Buildings and physical advantages (proximity to oceans, rivers, trade routes, or freeway interchanges) can help start a great city and aid its growth, but they cannot sustain its success. In the end, a great city relies on those things that engender for its citizens a peculiar and strong attachment that distinguishes one specific place from all others. Urban areas must coalesce around a consciousness that unites their residents in a shared identity. "The city is a state of mind," the great sociologist Robert Ezra Park observed, "a body of customs, and of unorganized attitudes and sentiments."

Whether in the traditional urban core or in the expanding periphery, issues of identity and community still largely determine which places will succeed. In this, contemporary city dwellers throughout the world struggle with many of the same issues that were faced by the originators of urbanity. Progenitors of a new kind of humanity, those earliest city dwellers found themselves confronting vastly different problems from those of prehistoric nomadic communities and agricultural villages. Urbanites had to learn how to coexist and interact with strangers from outside their clan or tribe. This required them to develop new ways to codify behavior and determine what was commonly acceptable in family life, commerce, and social discourse. In earliest times, the priesthood instructed on these matters. Deriving their authority from divinity, priests were able to set the rules for the varied residents of a specific urban center. In addition, rulers gained stature by claiming their cities to be the special residences of particular gods. The sanctity of a city was tied to its role as a center of worship.

Almost everywhere, the great classical city was suffused with religion and instructed by it. "Cities did not ask if the institutions which they adopted were useful," noted the classical historian Fustel de Coulanges. "These institutions were adopted because religion had wished it thus." In contemporary discussions of the urban condition, this sacred role has too often been ignored. Indeed, it barely appears in many contemporary books about cities or in public discussions of their plight. That would have seemed odd to residents of the ancient, classical, medieval, or even Victorian city. Today's "new urbanist" architects, planners, and developers often speak of the need for city green space, historical preservation, and environmental stewardship, yet they rarely refer to the need for a powerful moral vision to hold cities together. Their failure to do so is a natural reflection of today's urban environment, with its emphasis on faddishness, stylistic issues, and the celebration of the individual over the family or stable community. The postmodernist perspective on cities, dominant in much of the academic literature, even more adamantly dismisses shared moral values as little more than illusory aspects of what one German professor labeled "the Christian-bourgeois microcosmos."

Nihilistic attitudes of this sort, if widely adopted, could prove as dangerous to the future of cities as the terrorist menace. Without a widely shared belief system, it would be exceedingly difficult to envision a viable urban future. Even in a postindustrial era, notes sociologist Daniel Bell, the fate of cities continues to revolve around "a conception of public virtue: and the "classical questions of the polis." Cities in the modern West, Bell understands, have depended on a broad adherence to classical and Enlightenment ideals -- due process, freedom of belief, the basic rights of property -- to incorporate diverse cultures and meet new economic challenges. Shattering these essential principles, whether in the name of the marketplace, multicultural separatism, or religious dogma, would render the contemporary city in the West helpless before the grave challenges of the future.

This is not to suggest that the West offers the only reasonable model for achieving an urban order. History abounds with models developed under explicit pagan, Muslim, Confucian, Buddhist, and Hindu auspices, and the cosmopolitan city well predates the Enlightenment. In our time, perhaps the most notable success in city building has occurred under neo-Confucianist belief systems, mixed with scientific rationalism imported from the West. This convergence, an amalgam of tradition and modernity, eventually overcame Maoism, which was intent on destroying all vestiges of China's cultural past.

We must hope that the Islamic world, having found Western values wanting, may find in its own glorious past -- replete with cosmopolitan values and belief in scientific progress -- the means to salvage its troubled urban civilization. The ancient metropolis of Istanbul, with more than nine million residents, has demonstrated at least the possibility of reconciling a fundamentally Muslim society with what one Turkish planner calls "a culturally globalized face." The continued success of this cosmopolitan model, amid the assault from intolerant brands of Islam, could do a great deal to preserve urban progress around the world in the new century.

In an age of intense globalization, cities must learn to meld their moral orders with the ability to accommodate differing populations. In a successful city, even those who embrace other faiths must expect basic justice from authorities, as dhimmis (non-Muslims) did during the Islamic golden ages. If that expectation cannot be met, commerce inevitably declines, the pace of cultural and technological development slows, and cities devolve from dynamism to stagnation and ultimate ruin.

I believe that the urban experience is universal, despite differences in race, climate, location, and time. As the French historian Fernand Braudel once observed, "A town is always a town, wherever it