The federal government has long played a crucial role in connecting American cities to each other. But prior to the 1930s, most infrastructure projects within cities were carried out by local governments. Municipalities used tools such as franchise grants, special assessments, and eminent domain to work collaboratively with private investors. In the late 19th and early 20th centuries, cities developed an impressive capacity to plan, finance, and carry out projects themselves; after World War I, new public-benefit corporations took over some of these functions. Cities built roads, bridges, tunnels, water systems, electrical grids, and mass transit systems—all with relatively little help from the federal government. Washington and the states only helped by linking localities through interregional transportation and the Postal Service.

It was during the Great Depression that the federal government and cities began to collaborate in the development of urban infrastructure. In 1933, Congress and President Franklin Roosevelt created the Public Works Administration, which offered local governments grants-in-aid for large, capital-intensive construction projects; two years later, Roosevelt established the Works Progress Administration, which paid unemployed Americans to work on projects designed by local governments.

The success of both initiatives depended on the capacity and the imagination of both local and national officials; working together, cities and the federal government could do things that neither was capable of on its own. “We would have been awful damned fools,” WPA Director Harry Hopkins remarked, “if we thought for a minute that we have either the power or the ability to go out and set up 100,000 work projects ... without the complete cooperation of local and state officials. We couldn’t do it if we wanted to.” For enterprising local leaders—like New York City Mayor Fiorello La Guardia and public-works czar Robert Moses, both of whom built their towering reputations with the aid of New Deal spending—the New Deal represented, as one official put it, “a challenge and an opportunity ... to have done those things which make our cit[ies] more beautiful and useful, and which [we] on [our] own behalf would hardly ever be financially able to do.” In the span of a few years, the PWA and WPA helped build a staggering amount of infrastructure: airports, bridges, tunnels, subway extensions, parkways, schools, public beaches, college campuses, health centers, and public-radio broadcast facilities.

The initiatives of the 1930s established a new model of collaboration between the federal government and local authorities. In the postwar years, Congress replaced the New Deal agencies with a variety of targeted grant-in-aid programs—notably, to support the construction of hospitals and airports. The federal government also took on the role of supporting the nation’s water systems through regulation, quality assurance, and assistance, and in the 1960s it began to support the development of mass transit.