Levittown, brainchild of the brilliant, doomed real-estate developer William J. Levitt, was the opening act of a great American tragedy—the postwar explosion of suburban sprawl that turned us into a nation of motorists and plunged our cities into a bitter cycle of disinvestment and decline.

Levitt, who served with the Seabees during World War II, foresaw a huge demand for housing once the war ended. In 1946, he and his family began buying up vast tracts of farmland in Hempstead, Long Island; the …