This is maybe a stupid question, but why are you arguing against cars, especially in a place like Anchorage? Mike is right in another post where he points out that some place like Portland (or DC, or NYC, or SF, or Boston) is going to have support for a comprehensive public transit system by virtue of the type of people living in those cities. I would suspect that, despite potential environmental gains to be had, most Alaskans would still choose to drive over public transit, if only because Alaskans are stubborn and like their freedom from other people's schedules.