The Trump administration has undertaken an assault on the Environmental Protection Agency (EPA), an agency critical to environmental health. This assault has precedents in the administrations of Ronald Reagan and George W. Bush. The early Reagan administration (1981-1983) launched an overt attack on the EPA, combining deregulation with budget and staff cuts, whereas the George W. Bush administration (2001-2008) adopted a subtler approach, undermining science-based policy. The current administration combines both these strategies and operates in a political context more favorable to its designs on the EPA. The Republican Party has shifted right and now controls the executive branch and both chambers of Congress. Wealthy donors, think tanks, and fossil fuel and chemical industries have become more influential in pushing deregulation. Among the public, political polarization has increased, the environment has become a partisan issue, and science and the mainstream media are distrusted. For these reasons, the effects of today's ongoing regulatory delays, rollbacks, and staff cuts may well surpass those of the administrations of Reagan and Bush, whose impacts on environmental health were considerable.