[ssiguy]

It has way more to do with simple car ownership rates. The US has a dynamic which Europe/Aus/NZ/Can didn't and still don't have to deal with...........race. Slavery and it's long legacy still plagues the US and this is evident in it's urban design. In the 50s, 60s, and ,to a lesser extent, 70s every single US city without exception suffered from "white flight"............the whites fled the increasingly violent inner cities and the blacks they didn't want to live beside or want their kids to go to school with. The times of white flight and "integration" go hand-in-hand.

The whites fled and took their jobs, spending power, tax base, and political influence with them to the suburbs leaving the inner cities much poorer, a rapidly declining tax base, a plunging population, and politically impotent. This backed up by a huge highway expansion program including riping thru inner cities uniformally being the black areas that were torn down and a powerful GM lobby that encouraged the destruction of streetcar lines, and you have a recipe for urban disaster.