I think it all boils down to how much oil is left? How much gas will India and China use ten years from now? How much pollution will we accept to squeeze traces of oil from rock and sand? My son is an engineer for an oil company and he tells me they're not worried. Many Americans are willing to put up an oil rig in their back yard if necessary to keep driving their car three blocks to the grocery store. A society based on increased consumption of a limited resource has predictable results eventually. Until we make a conscious choice in city / road planning like they did in the Netherlands, to most Americans, bicycles will always be either a toy or a sport, ... not a transportation alternative.