Yet 300 to 500 polar bears could be saved every year, Lomborg says, if there were a ban on hunting them. What's cheaper - trillions to trim carbon emissions, or a push for a ban on polar bear hunting?

Plastic grocery bags are being banned, even though they require less energy to make and recycle than paper ones. The country is being forced to subscribe to a modern version of transubstantiation, whereby corn is miraculously transformed into sinless energy even as it does worse damage than oil.

Conservation, which shares roots and meaning with conservatism, stands athwart this mass hysteria. Yes, conservationism can have a religious element as well, but that stems from the biblical injunction to be a good steward of the Earth, rather than a worshiper of it. But stewardship involves economics, not mysticism.

Economics is the study of choosing between competing goods. Environmentalists view economics as the enemy because cost-benefit analysis is thoroughly unromantic. Lomborg is a heretic because he treats natural-world challenges like economic ones, seeking to spend money where it will maximize good, not just good feelings among environmentalists.

Many self-described environmentalists are in fact conservationists. But the environmental movement wins battles by blurring this distinction, arguing that all lovers of nature must follow their lead. At the same time, many people open to conservationist arguments, like hunters, are turned off by even reasonable efforts because they do not want to assist "wackos."

In the broadest sense, the environmental movement has won. Americans are "green" in that they are willing to spend a lot to keep their country ecologically healthy, which it is. But now it's time to save the environment from the environmentalists.