The history of America is a series of migrations from rural/suburban to city centers and back again.

Businesses and good jobs start to concentrate in urban downtowns, then the city gets too dense or polluted or expensive, people migrate for a better life to raise kids in a commutable distance based on the tech available (street cars, railways, cars), they go too far for the kids to find a job nearby when they are of working age, and then the kids move back to the city.. and the cycle restarts anew.