The DU Lounge

Edwin Moses, the infamous "master builder" of NY, was responsible for the early proliferation of parkways, intended to make driving a pleasure for the leisure class. Bridges were deliberately bulit low to keep buses (which were packed with "undesirables", in Moses' view) out, and to keep those nasty urban folk away from the beaches. The construction of transportation infrastructure in NYC, and in many other areas influenced by Moses and his "disciples" acting as consultants, favored private cars over public transport, and many potentially congestion-relieving mass transport lines were blocked from development in favor of parkways and freeways.

Caro's book is an amazing read; much of the political aspect is succinctly summarized in the Wiki article.