[idle_zealot]

There is a positive spin on this: the majority of Americans already live in or near dense urban centers. If we had solid public transportation only within these centers and to adjacent suburbs we would eliminate most car trips. That's bot much physical area to cover.

[lenerdenator]

Depends on what you consider "in or near".

I live "in" a major American city. Well, a reasonably major Midwestern city. It's roughly a third the size of Rhode Island. It has half a million people in it.