Earth Day and the Environmental Movement

In the context of the environmental movement in the United States during the period of 1945 to 1980, significant legislation and activism emerged to address environmental degradation. In 1970, the National Environmental Policy Act (NEPA) was enacted, which mandated federal agencies to prepare detailed environmental impact statements (EIS) for projects. This legislation marked a pivotal moment in federal environmental policy. Which of the following events or movements directly contributed to the public support for NEPA and the broader environmental movement?