The year 2020 marks several golden anniversaries in U.S. environmental policy. On July 9, 1970, President Richard Nixon signed an administrative reorganization plan that created the U.S. Environmental Protection Agency (EPA). Prior to that point, federal responsibilities for activities such as pollution control and chemicals regulation were limited in scope and scattered throughout different parts of the federal bureaucracy. The new EPA consolidated numerous existing federal authorities, including the National Air Pollution Control Administration, the Bureau of Water Hygiene, the Bureau of Solid Waste Management, and the Bureau on Radiological Health, from the Department of Health, Education, and Welfare, the Federal Water Quality Administration from the Department of the Interior (DOI), and three separate agencies responsible for pesticides control, including operations within the Department of Agriculture that had managed pesticide registrations (Williams 1993). This reorganization combined what had been disparate agencies, housed in different cabinet departments with varying organizational cultures, into a fledgling agency with a new shared mission to protect human health and the environment. It is also the 50-year anniversary of several legislative achievements in the area of environmental protection and natural resource management. On January 1, 1970, President Nixon signed the National Environmental Policy Act (NEPA) into law. This statute, inspired by the work of an Indiana University political scientist, Lynton Caldwell, created the White House Council on Environmental Quality to coordinate federal policy on the environment, and required federal agencies to prospectively consider the environmental impacts of their major decisions (Wertz 2014). By requiring agencies to evaluate the environmental impacts of their actions, Congress signaled to the vast federal bureaucracy that agency decisions must at least be conscious of their environmental impacts. Later the same year, Congress passed the landmark federal Clean Air Act (CAA) of 1970. This statute, which former EPA Administrator Gina McCarthy recently referred to as "one of the most successful public health laws ever enacted" (McCarthy and Burke 2017), systematically reshaped the U.S. approach to air pollution control. Responsibility for air quality before the 1970 CAA rested with state and local government authorities, most of which lacked the requisite institutional and financial capacity and/or the political will to meaningfully address increasingly severe air quality issues (Davies 1970). The CAA gave the federal government, and specifically the EPA, the authority to regulate air emissions from stationary (e.g., power plants, refineries, factories, etc.) and mobile (e.g., cars, trucks) sources of air pollution through a combination of prescriptive ambient and technology-based standards. Fifty years later, the EPA's use of the CAA still creates controversy, and regularly meets staunch opposition from many industry groups, but its programs have proven re...