Transportation infrastructure has dramatically altered the form of cities. Whereas the extent of cities before the mid-nineteenth century was limited by the distance one could comfortably walk, (Jackson 1985) the invention of rail-based transit in the nineteenth century opened up the hinterlands to rapid, transit-oriented development (Jackson 1985; Black 1995). The invention of the automobile and the highway transformed cities once again, enabling massive peripheral growth of car-centered landscapes. (Lewis 1997) Despite these technological elements of transportation, we should not forget the political underpinnings of the system; both railroads and highways were constructed with substantial public subsidy, (Rose et al. 2006) and how these infrastructure subsidies are targeted is an inherently political matter. There is also a politics contained within the geography of transportation infrastructure; where infrastructure is placed (and who decides this) can have huge effects on urban development, (Black 1995) the mobility of the city as a whole, (Ladd 2011) and quality of life within neighborhoods, (Fein 2014) and is thus politically contested. Issues of race and class rise to the fore upon examination of these political planning structures and their choices, especially when we consider which localities have historically seen disruptive construction of transportation infrastructure (Bullard et al. 2004; Biles et al. 2014) While contemporary transportation planning tends to be more sensitive of local contexts, (Lowe 2014) this consideration can lead to highly fractured debates and a glacially-slow political process.
Contemporary issues around transportation politics in developed nations can be placed within a context of general deindustrialization and an uneven rise of a post-industrial service and high-tech economy. (Hamnett 2000) The material side of this deindustrialization is a major driving force of gentrification; the spatial vacuums left behind are frequently foci for urban transformation. Waterfront industries are turned into luxury condominiums, warehouses are converted into lofts, and (industrial) working-class neighborhoods become trendy. (Smith and Williams 1986) Transportation plays an important role in this process of gentrification, with transit infrastructure often developed expressly for the purpose of urban revitalization and gentrification. South Lake Union in Seattle stands as a vivid example of these processes, with this formerly industrial landscape (centered on freight rail and shipping) having been transformed by Paul Allen’s real estate and streetcar investments. Gentrifying cities have a unique transportation politics, with progressive politics split between competing notions of “green” urbanism and social justice. Since gentrification is most prevalent in cities with a substantial pre-automobile urban form, which are seeing growth of the service and high-tech sectors, (Hamnett 2000) it is closely associated with the transit-rich and pedestrian-friendly areas that urbanists champion as the environmental-responsible alternative to suburban sprawl. At the same time, displacement, and its associated loss of “authenticity” is widely recognized as a bad thing. Even attempts to reconcile urbanism and social justice can be problematic, given a landscape of gentrification. Cities seeking to simultaneously expand transit usage for ecological reasons and promote social equity may deliberately build infrastructure through traditionally poorer neighborhoods, in order to promote mobility, transportation equity, and greater economic opportunity. The realization of urbanist goals, however, requires that the infrastructure catalyzes denser development, and thus some degree of displacement, whether directly or via rising rents.