Despite their best efforts and those of their political and academic allies, the well-funded Green Movement is being marginalized — and this decline is likely to continue.

In fact, the Green movement has found itself in a bit of an environmental crisis. According to Gallup’s annual Earth Day Poll, environmental issues are next to last on the list of people’s major concerns, finishing just above race relations. More telling, 44 percent of those polled said that the economic concerns should take precedence over protection of the environment. That figure has risen from 23 percent in 2000 and 19 percent in 1990.

It’s not that the environmental movement has been hampered by lack of funds. Consider these budgets: $44.6 million for the Environmental Defense Fund; $4.8 million for Friends of the Earth; $9.2 million for the Union of Concerned Scientists; $46 million for the Natural Resources Defense Council; $10 million for Public Citizen; $15 million for the Center for Science in the Public Interest; $20 million for Greenpeace.

That’s a total of $150 million.

To understand the declining of the Greens, let’s examine the four primary reasons.

First, and most significantly, many of the initial goals of environmentalism have been achieved.

Just consider the traditional goals of the Green movement, and the progress towards those goals that have been achieved in recent years. We have cleaner air, cleaner water, and a more responsible attitude towards dangerous industrial byproducts. Gregg Easterbrook, writing in the Brookings Review says, “Arguably the greatest post-war achievement of the U.S. government and of the policy community is ever cleaner air and water, accomplished amidst population and economic growth.”

For example, Steve F. Hayward, a resident scholar at the American Enterprise Institute, points out that “in the United States, we have reduced every form of air pollution from 30 percent to 99 percent over the past 30 years. [O]zone has increased slightly, although emissions of pollution continue to fall. Because of a quirk in ozone chemistry, ozone levels can rise, even as emissions fall, but this will prove temporary — ozone levels will be lower 10 years from now. Developing nations are showing signs of following the U.S. model; air pollution in...