Maybe no other force has been as important for shaping the modern American city in the past century and a half than urban planning, and maybe no other city in the country has been so affected as Chicago. So the Chicago Architecture Foundation’s decision to name their latest exhibit Chicago Model City is appropriate, since Chicago is perhaps the model city to study if one wants to know the tremendous change, both positive and destructive, that urban planning can cause.

The centerpiece of the exhibit is a 320 square-foot model of downtown that takes up almost the entire atrium of the Daniel Burnham-drafted Santa Fe Building on Michigan Avenue. The buildings are computer-drawn and machined from biodegradable plastic resin, but the true pleasure isn’t in the skillful depiction of each building and its slight characteristics. Instead, it’s in the aesthetic of the city’s complete density that comes from the viewer’s bird’s-eye perspective, something not afforded to those walking down the Loop’s characteristicly cavernous streets. And for a bunch of plastic models, it’s surprisingly realistic.

While the model itself deserves commendation and appraisal, the historical material is what is truly eye-opening. The exhibit is organized according to what early Chicago city planners, including Burnham, wanted their city to be: global, connected, green, beautiful, and new. Each category heads a short history detailing that particular aspect of development. “Green City,” for example, covers 19th-century sanitation concerns all the way up to modern day efforts to retrofit buildings and reduce carbon emissions.

“Connected City,” which covers the development of transportation, is particularly fascinating. Old pictures of the El show the familiar elevated tracks but, as for the trains, instead of today’s sheet-metal get-ups, there’s a steam engine, regal and massive, pulling the other cars. Highways, though probably not as important to the CTA-dependent U of C crowd, have been replicated with careful attention to detail. Instead of merely explaining how eminent domain forced people out of their homes, the curators of the exhibit have found photos of the area that is now the Congress Parkway, before and after its construction. Before the 1965 construction, there was a dense cluster of low-rise housing. After 1965: a broad expanse of bare land and razed buildings crossed by a new highway.

The exhibit’s focus on the idea of urban planning, rather than, say, architecture, is readily apparent. While architectural style and space are important concepts that the exhibit considers, it is much more preoccupied with how the sensibilities of planners can have a powerful effect on a city. Sometimes, the exhibit suggests, the changes and its consequences, intentional or otherwise, are necessary. The transformation of Cabrini-Green, for example, from massive monolithic hellholes for the poor to low-density public housing is rightly praised, despite the funding hurdles that have popped up due to the financial crisis. Yet the exhibit also shows that the consequences of urban planning can be drastically harmful. “New City” addresses the failed attempts at revitalizing the South Side, with its misguided maxim of “Order out of Chaos.” (One almost imagines this coming directly out of an Ayn Rand novel.) Unfortunately, according to the urban planners of yore, including the influential architect Ludwig Mies van der Rohe, the new order was an issue best left to the experts, not those who actually lived there.

The urban planning-centrism of the exhibit demonstrates the development of the profession from then to now, from the intellectual elitism of Mies to the planners of today—idealistic people who believe ideas can mold a city, urbanists with a Boy Scout complex. So it’s no surprise that when the Olympics come up in the “Global City” section, the outlook is one seen through rose-colored glasses. The positives of an Olympic bid—the revitalization of neighborhoods, mainly—are displayed in big, bold print, while the opposing arguments—displacement and debt—are displayed below the former in thin letters and smaller font. Whether you agree with this position or not, it’s not that important nowadays. What is important is that it is these attitudes that shaped our urban environment and will continue to do so as long as people live in cities.