Earth Day came and went and it seems that hardly anyone noticed. The Washington Mall was nearly empty despite a Herculean attempt by the environmental movement to make this year’s Earth Day the biggest ever. Leonardo DiCaprio’s much- ballyhooed special on ABC Saturday night was the lowest-rated prime-time show of the week (it even got soundly thrashed in its time slot by a rerun of “The Pretender”). The number of usual “end is near” stories in the press was at an all-time low (“ABC World News Tonight” even gave E‑Day a kick in the teeth the night before by featuring a story trashing recycling), and politicians — highly attuned to even the slightest political vibrations — for the most part went about their business with a minimum of hysterics. Make no mistake: There is no joy in Green-ville.

Here’s the puzzle: an overwhelming majority of Americans identify themselves as “environmentalists,” and a clear majority tell pollsters that they sympathize with the environmental lobby’s agenda. Yet they refuse to march, refuse to tune-in and, for the most part, refuse to take electoral orders from the environmental high command.

The public’s environmental commitment is a mile wide and an inch deep. For instance, they vaguely want government to “do something” about global warming but scream bloody murder when gasoline prices temporarily go up a quarter or two. You can’t, however, reconcile low energy prices with a serious global warming action plan. Meanwhile, fuel-efficient cars grow cobwebs on lots and sell like snow cones in Siberia while SUVs and gas-guzzling luxury cars are hotter than July.

There are several factors at work here. First, environmental politicians have for so long pandered to popular opinion that they’ve put themselves in a policy cul-de-sac. The environmental leadership discovered long ago that any direct confrontation with American affluence and our modern lifestyle was doomed to failure. So instead it preached pain-free policy pabulum. For example, it argues that we don’t need to increase the price of energy to reduce greenhouse gas emissions; rather, we need to increase the efficiency with which we use energy. But a little Econ 101 will tell you that if you reduce the marginal cost of using energy (which is what happens when you increase the energy efficiency of, say, your air conditioner), the more energy people are going to consume. That helps explain why energy efficiency improved by 57 percent since 1949 but energy consumption increased by 323 percent over that same period.

Instead of blaming consumers for wanting more and better “stuff,” the environmental leadership blames Madison Avenue for brainwashing us into consumption. Sure, marketers attempt to discover potential consumer wants even before consumers know they “want” what’s being sold, but only the deluded think that corporate America is leading, and not responding, to discernable or latent consumer desires.

Second, environmental advocacy has become increasingly less serious, and Americans are reacting by taking it less seriously as well. If you’re serious about alerting the public to the supposed dire consequences of global warming, you don’t put SUV-driving, consume-in-a-day-more-than-entire-3rd-World-countries-consume-in-a-week celebrities like Leonardo DiCaprio front and center. After all, Martin Luther King led the civil rights movement, not Diana Ross.

Third, Americans are growing numb to the constant cries of wolf. Back in the 1960s, environmentalists told us the population explosion would cause civilizational collapse by 1990. It never happened, and even 3rd-World people are living longer, better-fed lives than ever before. In the 1970s, environmentalists told us that we would run out of oil and most other valuable resources by the turn of the century, plunging us into a new Dark Age. It never happened, and resources are cheaper today (that is to say, more abundant) than ever before. Later in the 1970s, the environmentalists told us that a new Ice Age was upon us unless we took drastic action to reduce pollution (which, we were told, clouded the skies, blocking the sun).

Now we’re told that it’s warming, not cooling, that’s the threat and that the four horsemen of the apocalypse are about to descend upon us. Yet during all this warming, crop yields are at record levels, the economy is humming along quite nicely and human welfare has never been better.

If everyone’s an environmentalist, then no one’s an environmentalist. And that’s fine with me. The environmental lobby, while it has its good points, is all too filled with pseudo science, quasi-paganism, self-righteousness and anticapitalist fervor for me to spill tears over its troubles. Its childish morality plays and economic know-nothingism too often get in the way of serious discussion about real environmental issues. Perhaps Earth Day’s flop last week means that we’ve matured enough to have that discussion.