Did we make a cultural mistake popularizing the car?

[Anomalocaris]

I suspect that the construction of the U.S. highway system toward the end of enabling more interstate commerce via trucks did as much to lead to the popularization of automotive transport as anything.  I don't know the story in other countries, but in the U.S., that and the replacement of intra-city rail lines with buses did a lot to drive the development of automotive technology.  Personal transport may have simply come along for the ride as a consequence of the scale of, and improvement in technology employed in the above.   A war in which motorized transport was critical probably didn't hurt either.

During early days of the Cold War the nuclear threat to the survival of the state is believed to consist largely of a relatively modest number (hundreds,  not tens of thousands) of inaccurate nuclear bombs that are exrremely powerful in order to obliterate soft and easy-to-hit targets like cities. The very extensive and capacious interstate highway system and omnipresence of personal automobiles was to a substantial extent seen by the Eisenhower administration as a strategic necessity during the early days of Cold War.   It was seen as the only way to swiftly evacuate major population centers in time of international tension.  

The ability to build such a highway system and populate it with enough cars to evacuate large cities was also seen as a something that would be far more difficult for the USSR to match than bombs, bombers and missiles. So the highway system and personal cars was seen as giving the US a critical but non-military advantage over the USSR in case of a nuclear war.