Would you mind putting in concrete examples the sentence "most Americans do not live in areas where you could reasonably live without a car". It's not a critique, I'm not american so I don't understand how could this be, given the level of development of the country and the proliferation of cities that you are supposed to have.
* The stores are generally large big-box stores that is often kilometers from ones' house; there are no small corner shops and restaurants, because they are illegal.
* If you're still determined to walk, you probably need to cross large, high-speed roads with short crossing times, and your origin and destination are probably separated from the road by a large parking lot. And you may not even have sidewalks or crossing facilities. Example: https://www.google.com/maps/dir/Panera+Bread,+143+Alexander+...
* Public transit in American suburbs is a joke. Because it's so hard to walk around, ridership is very low, making frequency hard to justify, causing even lower ridership. And this is before you consider that
Americans are anti-tax
American suburbs have an associated history with white flight post-segregation, so people often object to transit because it'll let "criminals" in