I'm of the opinion that everyone gets radicalized about something. For me, a native of Southern California, that was the realization that the physical landscape of my community was sculpted to encourage, ease, and incentivize car usage and ownership, at all costs. In my early years as an undergraduate in Ann Arbor, Michigan, I, for the first time, lived in a community where I could just... walk to places. I didn't need to drive, I didn't need to park, I didn't need car insurance, I didn't need to buy gas, I didn't need to sacrifice at least an hour of every day to the agitation and danger of automotive commuting.
Don't get me wrong; cars are both private (mostly) and flexible. There is good reason why so many people would prefer to drive, or be driven. But there is a serious cost to car ownership, especially for those that drive alone. Per mile driven, even with American cities festooning the landscape with free parking, abundant freeways, and sprawling neighborhoods, cars are expensive, inefficient, and dangerous. However, this trade-off is not adequately represented in American cities and society.
Systematic neglect, or outright demolition, of alternative transportation intrastructure, such as for trains, buses, streetcars, etc., has gone on long enough that most Americans don't seem to consider, or, if they do, think very highly of, any alternatives to the entrenched method of "Build more parking lots; add more lanes to the freeway; sell more cars; raise taxes on the inner city to pay for it." This has made American transportation more dangerous, more polluting, and less efficient than it could be, enforced by a tapestry of local and state governments over-regulating zoning and land use. In many neighborhoods communities, it's literally illegal to do something as simple as converting a single-family home into a duplex. Red tape prevents working Americans from expanding the housing supply, or making it denser, keeping our rents high and our commutes long.
It's one thing to tolerantly (and skeptically) read the rantings of a self-confessed radical. It's another thing to see the full costs of American car ownership for yourself, laid out by publicly available data, including from sources deeply friendly to the automotive industry. It is my sincerest hope that the average American (and those that may idolize our car-dominant urban planning) might see what we are doing and come to believe that there must be a better way.