suburban sprawl planning was originally a cold war “civil defense” response

In 1945, the Bulletin of the Atomic Scientists began advocating for “dispersal,” or “defense through decentralization” as the only realistic defense against nuclear weapons, and the federal government realized this was an important strategic move. Most city planners agreed, and America adopted a completely new way of life, one that was different from anything that had come before, by directing all new construction “away from congested central areas to their outer fringes and suburbs in low-density continuous development,” and “the prevention of the metropolitan core’s further spread by directing new construction into small, widely spaced satellite towns.”

https://www.treehugger.com/why-sprawl-was-caused-nuclear-arms-race-and-why-matters-more-ever-today-4854403