Three years ago, when I first moved to D.C. and started writing for liberal magazines, it was considered hopelessly niche to care about decreasing Americans' reliance on cars. Supporting ideas like gas taxes and smart growth suburban development got you labeled an urban-triumphalist with little understanding of how most Americans "chose" to live their lives. As someone who grew up in a small town before living in several large cities, I'm well aware that in most American places, the simplest tasks -- from buying food to taking one's child to the doctor -- are impossible without an automobile. But a potent combination of environmental and economic concerns have completely changed the tone of the public debate around these issues. In a New York Times "Room for Debate" forum today on the topic of a "car-free America," every single contributor agrees that moving quickly toward less car dependence is a good idea. The debate is not between car-defenders and car-haters, but rather between those, like J.H. Crawford, who believe cities should follow the Venetian model and be totally car-free, and those, such as Witold Rybczynski, who urge "car-appropriate" lifestyles. Rybczynski claims that only six American cities have downtowns dense enough for a mass transit-dependent lifestyle: New York (midtown and downtown), Boston, Philadelphia, Chicago, and San Francisco. This will come as news to those of us who live in Washington, D.C. and Brooklyn without cars, just to name two communities in which I've spent a lot of time. But while the childless lifestyle without a car is rather easy in a number of mid-sized cities, things get substantially more complicated when you're responsible for ferreting a small, fussy person around to all their activities, while still being on time yourself. Any parents out there have experience with the car-less lifestyle outside of Manhattan? Any childless people who are making car-lessness work in cities other than the ones I've discussed here? --Dana Goldstein