Environmentalists are used to wallowing in misery–in fact, it makes them happy–but the 40th anniversary of Earth Day this week should offer up an extra helping of woe, for the movement has lost its mojo. Opinion surveys show not only that public belief in and concern for global warming is plummeting, but that environmentalism in general is falling out of favor. They have no one to blame but themselves.

The first Earth Day in 1970 was a sensation, amounting to a coming out party for a major new social and political force, and for the next decade the environmental movement became arguably the most rapidly successful social movement in U.S. history, with a string of landmark national statutes passed in quick succession with large bipartisan majorities, such as the Clean Air Act, the Clean Water Act, the Endangered Species Act, and culminating in the Superfund toxic cleanup act in 1980. But the field has been stagnant ever since, with environmental issues becoming highly polarized on ideological lines resulting in a complete stalemate on new legislative policy initiatives (though environmentalists are still thriving in the courtroom and in the bureaucracy).