Down a Ribbon of Highway

Throughout the 1960s, the Government marshaled extraordinary resources to accomplish a pair of Promethean feats: Americans were dispatched to the moon, and the country was overlaid with a brand-new web of nonstop superhighways. The space program remains a source of national pride. The Interstate Highway System? Most people take it for granted, except when they hit an unfinished stretch and find themselves rerouted along old, slow roads. Yet the Interstate has had a singularly profound effect on the way Americans live.

A comprehensive system of national highways was clearly necessary by the 1930s. In 1944, Congress, recognizing that a high-speed federal...