The freedom to go anywhere and become anyone has profoundly shaped our national psyche. Transforming our sense of place and identity--whether in terms of social and economic status, or race and ethnicity, or gender and sexuality--American mobility is perhaps nowhere more vividly captured than in the image of the open road. From pioneer trails to the latest car commercial, the road looms large as a form of expansiveness and opportunity.

Too often it is the celebratory idea of the road as a free-floating zone moving the traveler beyond the typical concerns of space and time that...