Outside North America, people don’t head downtown. Around the world they go to the city (Greek poli, Arabic al-Madinah, Russian gorod) or the center (from the Greek kentron to the Latin centrum, Spanish centro, and German Zentrum). The English, French, and Chinese combine city and center to form city centre, centre-ville, and shir jong hsin. Germans talk of the inner city, or Innenstadt. Italians and Poles speak, respectively, of the historic center (centro storico) and the old town (stare miasto). Australians and South Africans use an acronym, the CBD or Central Business District, a concept Americans consign to urban planning manuals. All these terms expose ideological biases in the way citizens regard the urban core. “City” appears all-inclusive, yet is differentiated from outer, newer districts. “Center” assumes a middle or innermost point around which lie peripheral places. Centro storico correlates historical buildings with the center, while stare miasto emphasizes the importance of the earliest settlement. So it is significant that downtown, in American parlance, designates neither the city at large, nor a central, inner location, nor the oldest part of the city. Such references would attach too much worth to a particular location or past accomplishment.

Downtown may have originally referred to a place that was lower and hard by the waterfront — the “down town,” in contrast to the “up town” further inland and higher in elevation. Manhattan likely inspired the concept. Urban settlement began at the island’s southern tip and over time proceeded northward onto higher ground. Indeed, the topographic basis of the word downtown sets in motion a progression to midtown and uptown, and later to suburbs and exurbs. It links the American city’s morphology and development with movement and improvement, with linear elongation and neighborhood succession.

The association of downtown with the harbor evokes the origin of American cities via great sailing ships plying oceanic trading routes. Yet the earliest colonial urban development in North America also proceeded in ways that recall later suburban development. All along the Atlantic shore, colonists from Great Britain and other European states founded settlements in environments with scant history of prior urbanization. Unlike cities in other regions that were founded atop older built foundations and cadastral patterns, the first colonial cities in the lands that would come to make up the United States of America were created ex nihilo, often drained from marshes or cut from forests. These cities grew from distant metropolitan centers but were separated from them by thousands of miles of ocean. Shipping lanes, the freeways of their age, connected the transoceanic “American suburbs” to their home cities, like London or Liverpool, and to sources of capital, labor, and finished goods.

On the landward sides of these cities lay the endless reaches of the continent. And while the earliest settlements were bounded by stockades, evidence of the violent wresting of land by European settlers from Native American bands and tribes, by the 18th century the young and prospering cities increasingly opened up to their surrounding landscapes.

Unbounded

The absence of city walls is notable. Encircling walls had been a feature of urbanization for millennia and, until the modern era, fortified walls protected cities in Europe and Asia from predation by other urban civilizations as well as from the devastating raids of nomads. In contrast, the small, rapidly growing cities of colonial America made due at first with wooden stockades and later with flexible defensive infrastructures; the sheer distance of threatening forces meant that militias, and afterward a standing army, police force, and network of forts and prisons, sufficed as protection.

To this day, the paucity of walls along American streets attests to the nation’s long history of urbanization without walls — and helps explain why gated communities often seem so startling. It was in fact the absence of walls that set American cities apart from most old world development.

In the old world, cities usually possessed several circuits of walls: one circuit enclosing agricultural fields and sparse settlements; another protecting the primary urbanized area; and still others, inside the city, demarcating royal, religious, and military compounds. This was the case throughout continental Europe (with the notable exception of Britain). In China, capitals were subdivided into progressively less accessible parts, from the outer city to the inner city to the Imperial City to the Forbidden City. Across Eurasia, not only did walls fix the geographical extent of a city; they fostered urban hierarchies, signifying where notables or commoners resided, where worship or trading took place, where citizen, second-class citizen, and outsider resided.

Walls instituted a grammar for old world urban morphology, structuring circulation networks and establishing development patterns. Gates were fulcrums between roads leading in and out of the city. Wider, straighter arteries led to prominent religious and administrative buildings near the center; narrower streets meandered into residential districts. In Islamic cities, the widest, straightest streets led from main gates to the central congregational mosque where Friday sermons were given. Radiating out from the mosque along the main arteries and then collector streets were other religious buildings, like madrasas, and then the souk/bazar, the city’s economic hub. The most esteemed shops, selling religious texts and items, were nearest the congregational mosque. Further out were craft workshops and shops, and then food processors and vendors, giving way, finally, to mahallas, or residential quarters. An Islamic city’s center, its confluence of principal streets and religious institutions, culminated in an architectural interface of domes or iwans, thresholds to the divine realm; but it also constituted a social interface between trading networks and the substance of local life. And in all the cities of the old world, wherever they arose, walls fostered an acceptance of communal planning regulations, tall residential districts, and high population densities.

Walls instituted a grammar for old world urban morphology, structuring circulation networks and establishing development patterns.

High population densities. Except in rare circumstances — in cities confined by island or peninsular geography, like Boston, New York, and San Francisco — these have been uncommon in the American setting. Residential densities have been especially low as measured by world standards. Even as the nation transitioned from agrarian settlement to urban industry, the detached house remained the preferred dwelling option (condominiums did not become a widespread real estate option until the 1960s — far later than in other parts of the world). Indeed, residential real estate speculation has long powered the economy in many parts of the country. This should not be surprising. The land surrounding American cities wasn’t tied up by royal or state ownership, and its easy exchange allowed for unprecedented urban expansion — or sprawl.

Gridded

Most American cities are characterized by a regular appearance. Typically there is a single, right-angled grid or collection of aligned grids; very occasionally, as with Washington and Detroit, a grid overlaid by radial boulevards. Already, in 1683, William Penn’s platting of 1,200 acres between the Delaware and Schuylkill Rivers established the grid as basis for the future city of Philadelphia. Grids, like walls, are powerful shapers of urban form. They mathematize urban land, apportioning it into rectilinear streets, rectangular blocks, and buildable lots. In setting forth repeating street widths and block/lot dimensions, grids smooth real estate transactions and standardize construction. Grids idealize a city’s existence well before its realization; the history of American urbanism is rife with struggles to force enterprising citizens to build according to a paper plan, and not subdivide blocks or build atop lands allotted for public squares. In much the same way that America itself was a visionary project undertaken by diverse European settlers, its gridded cities were idealistic instruments for projecting new concepts of inhabitation, economy, and society.

America’s gridded cities were instruments for projecting new concepts of inhabitation, economy, and society.

Long before 20th-century modernist urbanism, American streets were uncommonly wide and building lots uncharacteristically spacious. After the Land Ordinance of 1785, practically the entire nation between the Appalachian and Rocky Mountains was apportioned into one-mile sections. Most downtowns founded after that time followed the national grid, featuring wide, principal avenues and narrower collector streets. The overall uniformity of the grid created a framework where functional uses (e.g., industry or commerce or residence) could flexibly locate and relocate given changing marketplace demands. Thus, even as grids favored architectural and constructional homogeneity, they spurred socio-economic mobility.

Grids precipitated growth and expansion. Streets ended not in cul-de-sacs or fortifications. They projected outward. In many old world cities, the cadastral pattern of the center, bounded by walls, is sharply distinct from that of outer districts, which developed later. Not so in America, where endless straight avenues were plowed straight from downtown to uptown and then to the suburban districts. Along the route the character of an avenue would change, but less as a consequence of prior urban morphologies than as a reaction to current real estate economics. The siting of a new wharf or factory or residential neighborhood might suddenly favor the launching of a new manufacturing district or establishment of a particular street as principal commercial artery. American cities have been notable for the rapid creation and equally rapid outmoding of downtown sub-districts. Just as the capitalist city is a vehicle for the exchange of goods, services, and ideas, so the grid is a cadastral system favoring the exchange — or easy transfer — of said functions from one downtown area to another and, eventually, out of the downtown altogether.

Plural

The physical makeup of a city reflects and reinforces its socio-economic system. Not only has the American downtown been unconstrained by walls and regularized by grids; American society, with its emphasis on capitalism and individualism, has been unencumbered by long-lasting social relationships and their crystallization in monuments and plazas. In Christian Europe, the leading social castes, nobility and clergy, based their status upon deeply rooted historical relationships. Within a European city, the centrality of a cathedral, surrounded by monasteries and parish churches, epitomized the heavenly order. Likewise, the ruler’s palace, near the heart of a city, was the epicenter of a feudal regime reaching from town to territory, from the pinnacle of the landed aristocracy to the peasant masses. Civic buildings and market halls typically were clustered near the cathedral and castle, associating their status (and architectural style) with the longstanding institutions of church and aristocracy.

American society, with its emphasis on capitalism and individualism, has been unencumbered by long-lasting social relationships and their crystallization in monuments.

Permanent and universally shared monuments and civic squares are the exception in U.S. urbanism. American downtowns possess parks, but these spaces function as interludes within the urban bustle. We do not find European-style plazas, environments shaped and animated over the centuries by complex power dynamics among city factions and classes. In central Moscow, Red Square (Krasnaya Ploshchad) expresses the social history of the Russian capital over many centuries. The vast space is formed between the Kremlin (fortified citadel of the Tsars), Saint Basil’s Cathedral (the Orthodox Church), the GUM Department Store (emerging out of an older marketplace), and modern civic and political projects like the State Historical Museum and Lenin’s tomb. Nor do we experience anything like Buddhist temple compounds, providing an array of religious, socio-economic, and open-space functions to a society sharing a common system of belief. In Southeast Asia, the true civic spaces are the wats, walled compounds containing places of worship and education as well as kitchens and gardens.

American cities have never been dominated by a single religion. Alongside the Episcopal Church of the early English colonists, there arose an astounding variety of Protestant denominations, not to mention sizable communities of Catholics and Jews, and much later Muslims, Buddhists, and Hindus. And over time, religious diversity and secularism took deep root to the point where it would have been impossible to center any North American downtown around a singular spiritual edifice. This is markedly different from the typical Latin American city, where the walled streets of the centro converge on a plaza faced by a Catholic Church and a Spanish governor’s palace — urban embodiments of religious homogeneity and a hierarchical society.

The American downtown was de-centered by the mobile tendencies of its business activities and social networks.

Early on the Revolution irrevocably severed the Americans from the British monarchy and its royal tentacles. Hence we find no palaces. While city halls and governmental buildings establish a civic presence downtown, the nuanced layers of the American political system — federal, state, county, and municipal levels; legislative, executive, and judicial branches; quasi-governmental authorities like water and power companies — led to an imperfectly coordinated proliferation of offices, courthouses, libraries, and auditoriums across a downtown. City halls were frequently rebuilt and relocated, both to provide larger and more imposing quarters and to coordinate their positional geography with other expanding official edifices. To be sure, calls for consolidation of governmental buildings in a specially designed civic center were common, especially during the City Beautiful era at the onset of the 20th century. But even in cities like Denver and San Francisco, notable for their elaborately realized civic centers, this impetus did not result in the centralization of diverse urban activities. Usually situated on an edge of downtown, civic centers acted as centrifugal forces. Instead of an old world spatial fixity of monuments and squares, the American downtown was de-centered by the mobile tendencies of its business activities and social networks. The un-walled, gridded, and functionally flexible American downtown embodied the American mythos, that fictitious yet inspiring idea that social and economic advancement was possible for everyone.

Disruption

Beyond the cities of the Atlantic coast, the American downtown grew up during the industrial era, during a time of high technological innovation and almost ceaseless disruption. This would prove consequential. For what later came to be called downtown was once synonymous with the entire city. There you’d find a mix of residences, businesses, factories, government buildings, and halls of worship. But as industrialism ramped up in the late 19th century, the once compact American downtown faced an historic challenge. It could either spread outward while maintaining the prevailing pattern of mixed uses; or it could split apart and expand as a series of spatially and functionally discrete zones. Because of the indeterminate grid, because of the scarcity of fixed monuments, because the nation industrialized more rapidly and completely than any other during this era, it was the latter approach that predominated. Over decades, diverse functional types — factories, residences, churches — relocated to distant districts, and by the early 20th century the typical American downtown had become a zone given over almost entirely to commerce and (sometimes) civic affairs; gone were the factories and (in most places) the residences.

It happened fast. Seaports, warehouses, and manufacturing plants were growing rapidly and seeking larger tracts of land and modern facilities, well beyond the old wooden wharves and cramped factories of downtown. Since the mid-19th century, railroads had been providing a new, potent channel for the transportation of goods, and industries gradually aligned their facilities along the proliferating trunk and spur lines. Those same decades, commuter rail lines were allowing more affluent citizens to decamp for the hinterland, resulting in the birth of the planned, rustic suburb; on an even greater scale, cable cars, trolleys and, in a few cities, elevated and subway lines, spun out middle-income residential districts beyond the confines of downtown. Invariably these neighborhoods were segregated by race. Despite the American city’s remarkable commercial flexibility and religious diversity, there remained, from the 19th through the 20th century, a rigid barrier between blacks (and often Asians and Hispanics) and whites living alongside one another (or sharing spaces of almost any kind in the Jim Crow South).

The walking city exploded into the radial rail city, and downtown was transformed into a specialized commercial district.

In a remarkably short period of time, the walking city exploded into the radial rail city, an expansion in size many times over. In turn, downtown was transformed into a specialized commercial district within an expanding metropolitan region of specialized manufacturing and residential districts. Along its aging streets, residential populations shrank. Only a few cities, like Philadelphia and Chicago, retained downtown enclaves of wealthy residents. In most places the downtown became a residential zone of last resort, housing the poor and working class (and increasingly blacks) in cheap apartments, boarding houses, and residential hotels.

The American downtown entered the 20th century as a stronghold of commerce. Steeples, spires, and smokestacks had given way to theater marquees and skyscrapers. The turn-of-the century transit lines dispersed residences — but not offices. The high-rise office building – accommodating the new legions of administrators and managers — became downtown’s archetype. Nowhere in the world had the center of a city ever become so identified with a single building type and, for that matter, a brand new type — created only in the closing decades of the 19th century. The new skyscrapers — enabled by the invention of the elevator and steel-frame construction — housed corporate headquarters, newspapers, lawyers, accountants, etc. Soon the high-rise skyline became the visual symbol of the American city. When office skyscrapers were later built in Paris, Milan, Mexico City or Tokyo, et al., their presence signaled Americanization — an intrusion into the old, historic city much like the American imprint on cuisine made by soft drinks, fast food, and supermarkets.

The high-rise office building became downtown’s archetype. Nowhere had the city center ever become so identified with a single building type.

Unlike the old city centers that were anchored by a cathedral, mosque, or citadel, the skyscraper downtown was centered, precariously, on a real estate equation: the one hundred percent corner. A commercial calculation determined by pedestrian density and access — as measured by the convergence of mass transit lines bringing in commuters and shoppers — the one hundred percent corner became a mobile spot hosting the tallest buildings and commanding the highest rents. It established circumferential zones of values from a central area of prestigious corporate headquarters (“Class A” in today’s terminology), to outlying districts of smaller offices and back offices, and finally to a metropolitan edge of warehouses, produce markets, and light industry.

In its heyday, the decades leading up to the Great Depression, the American downtown boasted many other commercial ventures, especially retail, hospitality, and entertainment. Alongside the offices were department stores, major hotels, movie palaces. These too were mobile. Department stores frequently relocated, erecting larger and more fashionable facilities along newly prosperous streets — an outward march in the direction of high-end residential suburbs that served to expand the size of downtown. Shops, hotels, and theaters soon followed, as did the one hundred percent corner. Thus was development stratified along a linear route that began “down town” by the waterfront, the oldest and de-capitalized section, and which progressed “up town” toward the original rustic suburbs, those districts established decades earlier as an escape from industry and commerce. And because of the purchasing pull of the upper- and upper-middle classes, a city’s principal churches and synagogues often found it advantageous to relocate toward the “inner-city suburbs” in what often became a “religious district” on the downtown’s leading edge of growth.

Automobiles

The historical geography of the American downtown might be described as a series of strikes toward frontiers of opportunity brought about by economic breaks and abetted by technological advances. As long as rail transit predominated, those strikes occurred along continuous linear corridors. Yet, starting in the 1920s and accelerating after the late ’40s, the rise of the automobile and its revolutionary road system — the limited-access highway — blew all the old equations apart.

In the postwar decades, limited-access roads became a national preoccupation.

Automobiles and high-speed roads allowed practically everybody — individuals, businesses — to populate the vast metropolitan reaches between and beyond rail lines. Cities like New York and Los Angeles had experimented with parkways before the Second World War. In the postwar decades, limited-access roads became a national preoccupation. In 1956, the Federal-Aid Highway Act began the process of laying down what would become a 41,000-mile network of highways, many of which were built within metropolitan regions. Unlike Germany’s Autobahn or Italy’s Autostrada, which connected cities yet whose strips of undulating concrete were confined to the urban outskirts, America’s interstate highway system catered to both inter- and intra-city travel: the long haul, the commute, the errand. Highways quickly recast downtown in ways unimaginable to inhabitants of the walking or rail city.

In cities across the country, multi-lane high-speed roads blasted through urban neighborhoods and took up residence along waterfronts and rail corridors. Highways along the East and Hudson Rivers girdled Manhattan. In Boston, the elevated Central Artery ran roughshod through downtown, severing it from the waterfront and older neighborhoods like the North End. The new roads functioned as both connectors and separators; in effect, as the shipping lanes as well as the walls and moats of late 20th-century urbanism. Nonetheless, American downtowns avoided some of the worst excesses of automotive urbanism. In East Asian cities, from Tokyo to Shanghai to Bangkok, elevated highways slalom through the high-density urban cores, and skyscrapers aren’t centralized but spring up along the roadways and mass transit routes. The cityscape is disconcerting to those attempting to navigate it on foot. Flyovers interrupt streets. Expressway-like roads, but with plentiful access, prevent pedestrian crossings; people are often routed up to sky bridges or down to underground passages. In Dubai, Sheikh Zayed Road, a monumental twelve-lane highway bordered by a rail line and service roads, serves as the distinctly automotive main street/moat of the city.

But if in many Asian cities highways helped generate skyscraper development, in American cities the new expressways hollowed out the old downtowns. Long-time commercial uses, like offices and stores, either closed or migrated to a progressively more distant suburban periphery. Companies seeking office space turned to low-rise edifices on huge tracts of land replete with free parking and extensive landscaping — what has come to be known as the office park or corporate campus. Sprawling shopping centers set up operations alongside interchanges of the new highways. A polycentric metropolis emerged, with downtown ringed at distances of fifteen to fifty miles by edge cities providing highly competitive shopping, employment, entertainment, and housing. This remarkable and now familiar phenomenon replayed the opening chapters of many American cities, where two or more districts had competed to be the main downtown. Yet now the once prosperous downtowns were threatened by a new car-centric system in which they had significant and structural disadvantages. Through the 1980s and even beyond, downtowns bled department stores, boutiques, hotels, and movie theaters. The American downtown was no longer distinctly commercial; increasingly the offices that remained were joined by civic and non-profit uses including local government, public colleges, and hospitals.

Postwar America enjoyed remarkable affluence — yet these were the decades that produced the nation’s great urban crisis. Everywhere the public commitments to downtown — to rail and mass transit, to pedestrians and poorer residents — were being reduced. Across the nation, coalitions of government and remaining downtown businesses fought back. Aided by federal programs and dollars, municipal redevelopment agencies undertook massive clearance efforts to cleanse downtown of so-called blight and slum conditions — all in the interest of so-called urban renewal. On the new superblocks where the cleared buildings once stood there rose new office towers and, sometimes, shopping malls modeled on the successes of the suburbs. The results were decidedly mixed. The commercial exodus was halted somewhat; some downtowns rallied; a few even revitalized their shopping districts. But many other downtowns, especially in cities whose economies remained tied to manufacturing, slid further into ruin. The displacement of poor and minority residents, the demolition of historic buildings and neighborhoods, the erasure of pedestrian-friendly streetscapes: overall these tore apart the downtown’s character and spirit. From coast to coast there emerged a new and degraded downtown where parking lots, over-scaled highways, and coarse-grained buildings suggested a wan and ineffectual approximation of the burgeoning suburbs.

American downtowns and their surrounding districts are noteworthy for their desolation — the lack of shops, restaurants, people.

American cities were not alone; other nations were experiencing similar urban dynamics. The great industrial cities of Great Britain suffered similarly drastic declines in employment and quality of life in the postwar decades. Throughout Latin America, the Spanish or Portuguese-founded centro was displaced from its preeminent socio-economic role by new suburban centers many miles distant. In Lima, both upper-end residents and commercial enterprises decamped from the centro to the San Isidro and Miraflores districts, decisively shifting the city’s financial, shopping, and entertainment centers of gravity. In Teheran, car-centric urban growth similarly marginalized the pa-een shahr, or lower part of the city, home to traditional trades and a rich mix of residents. Automobiles favored an unprecedented economic and social stratification, as higher income residences, tony shops, and new entertainments developed to the north of the city, in the bala shahr, or uptown. Still, the satellite downtowns created in Lima and Teheran, and in other cities worldwide, have been far more urban (e.g., conducive to mass transit and dense habitation) than the American edge cities, where automobile ownership became both a symbol and necessity of the times. Compared to cities across the globe, the streets of American downtowns and their surrounding districts are noteworthy for their desolation — their lack of shops, restaurants, people. The striking underdevelopment of the postwar American downtown was a product of the society’s ready adoption of infrastructural systems that radically re-distributed wealth, work, circulation, and population far beyond its confines.

By the early 1980s, downtown appeared a lost cause. It was burdened by aging, emptying office buildings, struggling discount retailers, and vanishing entertainment complexes. Cities large (Buffalo, Detroit, St. Louis) and small (Newark, Gary, Flint) experienced an altogether dramatic exodus of people and capital, their downtowns and surrounding districts coming to resemble ghost towns. Nor did further assistance seem imminent. Newly elected Republican President Ronald Reagan crusaded against government spending, cutting monies for mass transit, subsidized housing, and municipal redevelopment.

Revival

And yet, though only faintly discernable, rays of urban hope were appearing. For even amid the bleak years of mid century there were changes afoot that would work to shift entrepreneurial energy back downtown. The longstanding out-migration from downtown to suburbia served to ease many undesirable qualities of urban life, including congestion, crowding, noise, and pollution. The demolitions of urban renewal (or, as some have called it, “removal of poor and black people”) created in certain downtowns a kind of cordon sanitaire for new investment seeking suburb-like conditions. Likewise, the mix of abandoned buildings and depressed real estate values offered re-use opportunities to communities of artists and gays and later the new urban professional class. In many downtowns, the oldest district, the working waterfront, was remade from a fetid eyesore into parkland and leisure zones. Historic preservation and architectural postmodernism led to legal protections and the aesthetic re-estimation of older buildings and streetscapes. Meanwhile, the suburbs and their mounting problems — including congestion: this was where the traffic jams had migrated too — raised the value of a central location well served by mass transit. And all the while, the reorientation of the economy from production to consumption and from the marketing of social conformity to the promotion of diverse lifestyles favored a reappraisal of the unique physical environments of downtown America. By the start of the new millennium, the onetime fascination with convertibles and sod lawns was giving way to an embrace of public transportation and gardens set on rooftops.

The onetime fascination with convertibles and lawns was giving way to an embrace of public transit and rooftop gardens.

A tightening of global connections further changed the makeup of America. The Immigration and Nationality Act of 1965 abolished quota regimens that had been in place since the 1920s, paving the way for an ongoing, large-scale migration from Asia, Africa, and Latin America. Demographics changed to the point where, by 2011, the U.S. population of European origin measured less than two-thirds. Many immigrants settled in older cities, sometimes in downtowns and surrounding neighborhoods, bringing communal vitality to once barren blocks and further contributing to the appeal of inner city living.

Movement across the oceans went both ways. Starting in the ’60s, affordable jetliners whisked growing numbers of once provincial U.S. residents overseas, first to Europe and then other continents. On family vacations and business trips, the wider world and its pulsing cities became familiar to Americans. They noticed that the centers of cities were home to the more affluent residents, while distant suburbs housed the poor. They marveled at the ongoing importance of historical monuments and at the continued investment in mass transit systems and public works. Some international “downtowns” turned into models for architects, urban planners, government officials — not to mention increasingly cosmopolitan Americans. Downtown became a new frontier.

The Southern California city of San Diego suggests the opportunities and challenges. In the mid 20th century, San Diego was known neither for the devastation nor revitalization of its downtown. The old core, mirroring cities across the nation, had become a largely mono-functional collection of office buildings and, in the metropolitan scheme of things, a distinctly lesser part of a rapidly growing region of suburbs. Downtown San Diego’s comeback may be dated to 1981, to the opening of the San Diego Trolley — the first of many new light-rail lines connecting U.S. downtowns to outer districts. In 1985, architect-developer Jon Jerde opened Horton Plaza, a shopping mall within several renovated downtown buildings — a compelling, if gaudy commercial environment that married old architecture and new graphics. A convention center, baseball stadium, and several hotels soon followed.

All of which raised the question: Might retail, tourism, and leisure-time activities be downtown’s salvation? Alas, although Horton Plaza was a success, most large-scale downtown shopping ventures failed. The mix of highway access, free parking, and corporate control that has long sustained suburban shopping didn’t translate well downtown. Nor were costly sports arenas or cultural venues geared to suburbanites and tourists enough to populate downtown streets. Baseball fans and museum patrons came downtown and then went home; in most places — like Baltimore’s Inner Harbor — only the immediate vicinity of the new development enjoyed any positive impact.

Something more was needed. It turned out to be housing.

The greatest transformation to the American downtown in recent decades — what has aligned it with global tendencies — has been the reintroduction of housing. The demographic underpinnings are various. Families and family values had changed since mid-century, and were no longer dominated by the nuclear ideal of husband, wife, and children. Fewer folks married or had kids. More people lived alone. Men and women, straights and gays, the elderly, students, people with disabilities, dwelled in an increasingly diversity of households, and demanded an equally diverse range of building types. Rentals and condominium ownership in apartment buildings or townhouses were sought after. Although many complexes were still built in the suburbs, a growing number were constructed downtown. Soon, formerly vacant downtown streets began to acquire a wholly novel residential cachet.

The greatest transformation to the new American downtown has been the reintroduction of housing.

This change in dwelling perception has been profound. In a society pretending to lack firm class divisions, practices of spatial separation had long fortified boundaries between white and black, native and immigrant, affluent and impoverished; the value of home ownership for affluent, white America had depended the absence of (and distance from) manufacturing, commerce, low-cost housing, and minority communities. Suburbs appealed far more than downtown, because the kind of housing sites attractive to developers were highly controllable parcels located not within but beyond the city.

The turn-of-the millennium downtown residential building boom has recalibrated those housing values. Planning ideology shifted 180 degrees from mid-century, promoting neither slum clearance nor green-field parcels. Instead, planners encouraged infill housing, mixed-use streets, and diversely populated districts, touting the advantages of locating customers close to businesses. The expanding appeal of condominium ownership led developers to consider sites scattered across downtown: next to warehouses, on busy commercial arteries, alongside highways, in black neighborhoods. What has been emerging in recent years is a downtown of rental buildings and condominiums with restaurants and bars, fitness clubs and local shops.

Planning ideology shifted 180 degrees from mid-century, promoting neither slum clearance nor green-field parcels.

Even more than retail and entertainment, the return of housing to downtown America reversed the outmigration of uses prevalent since the late 19th century. It set the stage for the creation of a wholly new kind of district — a new kind of downtown distinct from the early 20th-century commercial city, and from the post-war inner city surviving on government life support. Crucially, this new American downtown was less beholden to what had been the paradigmatic geographical dynamic: a linear progression from old to new, from outmoded to fashionable, from mixed race to lily white, from low to high in both a topographic and socio-economic sense.

The 21st-century downtown increasingly relies on its residents — not just commuters or shoppers or tourists — to populate office buildings, patronize shops, and frequent restaurants. In this regard, the more successful American cities are beginning to take on qualities of their European counterparts: the affluent dwelling in a central area graced by historic architecture and cultural institutions, and the poor relegated to outer city neighborhoods and low-end suburbs. Significantly, though, the recent downtown revival has not been for everybody. Mirroring the increasingly unequal distribution of wealth in the United States, model downtowns are geared to “model” Americans — the affluent. Hence their symbols: the luxury condo and gourmet restaurant.

Because of the focus on wealth, downtown revitalization has been spotty. Much earlier, at the onset of the 20th century, practically all American cities participated in the momentous commercial consolidation of downtown. Smaller versions of New York’s skyline or great white way appeared from coast to coast. The postwar decline also afflicted the entire country, though some cities held together their office and retail sectors better than others. Quite differently, in the first decades of the 21st century, the entertainment- and housing-based revival of downtown is selective when it comes to geography. Cities blessed with educated populations, high-technology economies, warm climates, and considerable environmental amenities have prospered, often to the point where stratospheric housing costs discourage all but the upper-middle and upper income class. In the cities of the snow and rustbelt, especially in the inland Northeast and Midwest — where people are poorer and less educated — downtown revivals have either been modest or nonexistent.

More than anywhere else in the world, development in the new American downtown is driven by the private sector.

Tellingly, to a greater extent than much of the rest of the world, development in the new American downtown is driven by the private sector. The era of federal largesse, lasting from the Great Depression through the 1970s, is long past. Over the past few decades, resistance to taxes and the burden of pensions have starved the public sector’s ability to fund new infrastructure and building projects, or even to maintain existing infrastructure. Unlike European and East Asian cities, even the most successful mixed-use American downtowns have been unable to construct a truly expansive and high-functioning transit net linking downtown to its suburbs, airports, and surrounding cities. Moreover, resistance to densification is rampant in affluent American neighborhoods, even in downtown. Compared to global high-rise cities like Seoul, Hong Kong, or Sao Paolo, or even a few American versions like New York, Chicago, and Miami, both the amount of housing and its density in most American downtown developments (and along new rail corridors) has been paltry.

Many questions remain. Will telecommunications and environmental concerns encourage shorter commutes, lowered energy bills and, hence, a turn toward more downtown residential skyscrapers? Might the popularity of condominiums even crowd out office buildings, making downtown a more intense version of older residential neighborhoods with shopping and services in walking distance? Could the current expansion of residences alongside businesses (especially businesses specializing in new technologies, health care, education, or artisanal manufacturing) spill over to districts surrounding downtown and result in a super-sized, mixed-use downtown taking up much of the inner city? Or might a collapse of white-collar employment brought about by robotic and digital automation dry up the sources of the kind of jobs that are sustaining the entire range of downtown development?

Historically, the American downtown was based on European precedents, and yet it took an exceptional course of development, one that favored a vibrant quest for opportunities over any allegiance to any fixed pattern, place, or building. But if the 21st-century American downtown appears less exceptional, it is not only because recent developments have brought it closer to old-world patterns but also because cities worldwide have been changing too: the old American mix of helter-skelter development coupled with flexible locational strategies has spread across the oceans. Worldwide, cities now sprawl across the countryside. Skyscrapers are ubiquitous. Automobiles, trucks, and motor scooters crowd the streets. Historic monuments, plazas, and early cadastral outlines have considerably less influence on the vectors of new development. Indeed, old centers constitute but a tiny fraction of the built-up area of many cities in South America, Africa, and Asian, and even some in Europe. Even the American promise of economic and geographic mobility — for people, businesses, and institutions — doesn’t stand out as it once did. While the United States has entered a post-industrial epoch of stagnating opportunities for working- and middle-class citizens, much of the developing world is experiencing sky-high urbanization rates — the kind of rural-to-city migration that fuels dreams of a better life while unraveling urban tradition.