National System of Interstate and Defense Highways

The modern American interstate system, so crucial to the development of suburbs and the internal mobility of Americans, had its origins in defense. In 1919, Dwight Eisenhower, then a lieutenant colonel, participated in the Transcontinental Motor Convoy, designed to test how readily the Army could move military resources overland from one coast to another. The convoy took 62 days to travel 3,251 miles from Washington, D.C., to San Francisco. Covering fewer than 60 miles per day, they arrived at their destination five days behind schedule. The convoy spent half its time on unpaved roads and experienced more than 230 accidents, most caused by poor roads or bridges that could not withstand the strain of the heavy Army vehicles.

To a logistically minded officer like Eisenhower, the convoy was a clear warning that the nation's road network was a logistical nightmare and vulnerable to sabotage. If agents of a foreign power managed to infiltrate the United States, they could virtually disable the nation's overland transportation network by demolishing a relatively small [Page 573]number of essential bridges and tunnels. Indeed, the designers of the convoy experiment had imagined just such a case and assumed that in wartime the trip would have taken even longer. Eisenhower later wrote that the Transcontinental Motor Convoy started him thinking about the creation of a much less fragile national network of two-lane highways to facilitate the movement of men and matériel.