Thanks to David Roberts for highlighting an article in the current Washington Monthly, "The Emerging Environmental Majority" (by yours truly).
Here's the quick version: Each time in American history that environmental concerns rose to the top of the national agenda, support for ambitious government action came from a broad array of groups responding to an impending sense of crisis.
Having spoken to activists, historians, and politicians of the 1960s and 1970s, I believe there are parallels between today's mounting public concern over global warming and the prelude to our nation's last great era of environmental reform. In the decade before "Earth Day," city-based citizen groups across America worked to control pollution, union chapters focused on mining safety, sportsmen's groups worried about watersheds, and women's organizations highlighted the connection between pollutants and fetal health. These groups had diverse focuses, but the broad chorus for reform made green concerns impossible to ignore. In the early 1970s, Washington produced the Clean Air Act, Clean Water Act, and Endangered Species Act, among other landmark laws.
Today public concern about global warming is approaching another tipping point. Climate-change campaigns are taking root among a widening spectrum of groups, from environmentalists to evangelicals, hunters to insurance companies, farmers to politicians. For ambitious measures to pass muster in Washington, global warming has to be seen, not as an issue for partisans, but as an issue affecting everyone.
Now, my original point was that David is one smart cookie (don't you agree?), and he raises some pertinent questions that I take a whirl at answering below.