# Highway Needs of the National Defense/The Interstate Highway System and Its Relation to National Defense

Layout 2
Washington, DC: United States Government Printing Office, pages 70–72
THE INTERSTATE HIGHWAY SYSTEM AND ITS RELATION TO NATIONAL DEFENSE
In the period between the First and Second World Wars the Public Roads Administration had at various times sought the advice of the War Department as to which of the many highways composing our total 3,000,000-mile system might be considered to be of principal strategic importance in the event of war.
The first of these inquiries was made in 1922. At that time the State highway departments and the Bureau of Public Roads were engaged in the selection of routes to comprise the Federal-aid highway system, designation of which had been required by the Federal Highway Act, then recently enacted. That act had made it clear that the contributions of the Federal Government to highway improvement would thereafter be confined to a system of principal highways, mainly interstate in character, and limited initially in each State to a mileage not exceeding 7 percent of the State’s total road mileage.
THE PERSHING MAP
The rural roads of the United States were then in large part unimproved. It was evident that the selection of certain roads for improvement with Federal aid would result in the earlier improvement of those roads. If there were some roads which were, in greater degree than others, important from the viewpoint of national defense, it was obvious that they should be included in the system then in process of designation, because such inclusion would assure their earlier improvement. Moreover, a basic reason for any concern of the Federal Government with the improvement of highways was the desirability of the improvement for the better discharge of particular Federal responsibilities, including the responsibility of national defense.
To the request of the Bureau of Public Roads for its indication of the most important strategic highways, for inclusion in the system to be improved, the War Department responded by supplying a map of the United States on which were shown the highways so regarded. This map, approved by General Pershing, has since been known as the Pershing map (fig. 9). The highways on it were included in the Federal-aid system as it was designated, and all of them have since been substantially improved.
THE STRATEGIC NETWORK
​ these further reviews coincided with those of the Pershing map, but there were some additions, and the latest of these were shown on a map, revised to May 15, 1941, and approved by the Secretary of War. It was the system shown on this map and referred to specifically as such in the Defense Highway Act of 1941 that became known as the strategic network (fig. 5).
The total length of the highways included in the strategic network is approximately 78,800 miles. Within a system of this extent, there naturally are differences of importance among the roads included, even while as a whole the system comprises the most important highways. In its review in 1941, the War Department indicated such distinctions among the routes included in the network. In general, it found that the routes of greatest importance coincided with those that had previously been chosen by the Bureau of Public Roads as desirable of inclusion in a system of interregional highways. This system had been proposed by the Bureau as constituting the principal trunk highways of the United States that should be preferentially developed as such with road-user revenues and Federal aid as an alternative to the construction of a smaller system of national toll roads.
STUDY OF INTERREGIONAL HIGHWAYS
His interest stirred by the suggestion of the Bureau, President Roosevelt, on April 14, 1941, had appointed a National Interregional Highway Committee to review the surveys and data upon which the suggestion had been based and to recommend a limited system of national highways designed to provide a basis for improved interregional transportation.
The report of this committee, entitled “Interregional Highways’, rendered to the Federal Works Administrator January 1, 1944, was forwarded to the President and by him, on January 12, 1944, was transmitted to the Congress with his favorable recommendation, in fulfillment of a request for such a report which had been made by the Congress 6 months earlier.
CONGRESSIONAL ACTION
Acting upon the recommendations of this report, the Congress, in section 7 of the Federal-aid Highway Act of 1944, approved December 20, 1944, directed that—
There shall be designated within the continental United States a National System of Interstate Highways not exceeding 40,000 miles in total extent so located as to connect by routes, as direct as practicable, the principal metropolitan areas, cities, and industrial centers, to serve the national defense, and to connect at suitable border points with routes of continental importance in the Dominion of Canada and the Republic of Mexico. The routes of the National System of Interstate Highways shall be selected by joint action of the State highway departments of each State and the adjoining States, as provided by the Federal Highway Act of November 9, 1921, for the selection of the Federal-aid system. All highways or routes included in the National System of Interstate Highways as finally approved, if not already included in the Federal-aid highway system, shall be added to said system without regard to any mileage limitation.
* ↑ Toll Roads and Free Roads, H. Doc. No. 272, 76th Cong., Ist sess.
* ↑ Interregional Highways, H. Doc. No. 379, 78th Cong., 2d sess.
* ↑ Amendment of the Federal Highway Act, July 13, 1943 (57 Stat. 560).
SELECTION OF THE INTERSTATE SYSTEM
Complying with this congressional direction, routes for inclusion in the authorized National System of Interstate Highways were selected by the several State highway departments, and a system composed of the routes selected, with minor modifications required to effect interstate continuity, was approved by the Federal Works Administrator, August 2, 1947.
The system then approved was composed of 37,681 miles. There remained at that time, within the 40,000-mile limitation fixed by the law, the authority to designate an additional 2,319 miles, which it was expected would be largely composed of desirable circumferential and distributing routes in urban areas.
Since the original approval of the system, a few changes have been made; and the system as presently designated, totaling 37,800 miles, is that shown in figure 1. The condition of the system so constituted was the subject of the study reported in the first part of this report. The balance of 2,200 miles within the 40,000-mile limitation is still reserved mainly to be comprised, after further detailed study, of essential circumferential and distributing routes in urban areas.