At the turn of the century a few thousand people owned cars; in 1922 about 10 million did, and that number more than doubled in the next few years. Sharing their need for decent roads were fast-growing fleets of trucks and buses. And the federal government was thinking big. Congress had just authorized funds to help states create a 200,000-mile web of smooth-surfaced roads that would connect with every county seat in the nation.

It was just a beginning. Ahead lay engineering feats beyond anything Durant could have foreseen: the construction of conduits that can safely handle thousands of cars an hour and endure years of punishment by 18-wheel trucks, expressways and beltways to speed traffic in and around cities, swirling multilevel interchanges, arterial tunnels and mighty suspension bridges. Ahead, as well, lay a host of social and economic changes wrought by roads—among them, spreading suburbs, the birth of shopping malls and fast-food chains, widened horizons for vacationers, a revolution in manufacturing practices, and a general attuning of the rhythms of daily life, from errands to entertainment to the personal mobility offered by the car. Expansion of the network would also bring such indisputable negatives as traffic congestion and air pollution, but the knitting together of the country with highways has barely paused since the first automobiles rolled forth from workshops about a century ago.

Rails ruled the transportation scene then. Like other developed nations, the United States had an intricate system of railroad tracks reaching to almost every sizable community in the land. Virtually all long-distance travel was by train, and electric trolleys running on rails served as the main people movers in cities. The United States also had more than 2 million miles of roads, but practically all were unsurfaced or only lightly layered with broken stone. A "highway census" performed by the federal government in 1904 found a grand total of 141 miles of paved roads outside cities. In rainy weather, travel in the countryside became nightmarish, and even in good conditions, hauling loads over the rough roads was a laborious business; it was cheaper to ship fruit by rail from California to an urban market in the East than to deliver it by wagon from a farm 15 miles away. As for anyone contemplating a lengthy drive in one of the new horseless carriages, an ordeal was in store. The first crossing of the continent by car in 1903 required 44 days of hard driving. By train the trip took just 4 days.