The Interstate Highway System was authorized by the Federal-Aid Highway Act of 1956 for the PRIMARY purpose of helping strengthen our national defense by creating an easier means of transporting people and goods in an emergency.
The Interstate Highway System, oficially called the Dwight D. Eisenhower National System of Interstate and Defense Highways constitutes a network of controlled-access highways that are part of the National Highway System in the United States. Its construction was authorized by the Federal Aid Highway Act of 1956.