I'm not a global warming believer. I'm not a global warming denier. I'm a global warming agnostic who believes instinctively that it can't be very good to pump lots of CO2 into the atmosphere, but is equally convinced that those who presume to know exactly where that leads are talking through their hats.

Predictions of catastrophe depend on models. Models depend on assumptions about complex planetary systems — from ocean currents to cloud formation — that no one fully understands. Which is why the models are inherently flawed and forever changing. The doomsday scenarios posit a cascade of events, each with a certain probability. The multiple improbability of their simultaneous occurrence renders all such predictions entirely speculative.

Yet on the basis of this speculation, environmental activists, attended by compliant scientists and opportunistic politicians, are advocating radical economic and social regulation. "The largest threat to freedom, democracy, the market economy and prosperity," warns Czech President Vaclav Klaus, "is no longer socialism. It is, instead, the ambitious, arrogant, unscrupulous ideology of environmentalism."

If you doubt the arrogance, you haven't seen that Newsweek cover story that declared the global warming debate over. Consider: If Newton's laws of motion could, after 200 years of unfailing experimental and experiential confirmation, be overthrown, it requires religious fervor to believe that global warming — infinitely more untested, complex and speculative — is a closed issue.

But declaring it closed has its rewards. It not only dismisses skeptics as the running dogs of reaction, i.e., of Exxon, Cheney and now Klaus. By fiat, it also hugely re-empowers the intellectual left.

For a century, an ambitious, arrogant, unscrupulous knowledge class — social planners, scientists, intellectuals, experts and their left-wing political allies — arrogated to themselves the right to rule either in the name of the oppressed working class (communism) or, in its more benign form, by virtue of their superior expertise in achieving the highest social progress by means of state planning (socialism).

Two decades ago, however, socialism and communism died rudely, then were buried forever by the empirical demonstration of the superiority of market capitalism everywhere from Thatcher's England to Deng's China, where just the partial abolition of socialism lifted more people out of poverty more rapidly than ever in human history.

Just as the ash heap of history beckoned, the intellectual left was handed the ultimate salvation: environmentalism. Now the experts will regulate your life not in the name of the proletariat or Fabian socialism but — even better — in the name of Earth itself.

Environmentalists are Gaia's priests, instructing us in her proper service and casting out those who refuse to genuflect. (See Newsweek above.) And having proclaimed the ultimate commandment — carbon chastity — they are preparing the supporting canonical legislation that will tell you how much you can travel, what kind of light you will read by, and at what temperature you may set your bedroom thermostat.

Just Monday, a British parliamentary committee proposed that every citizen be required to carry a carbon card that must be presented, under penalty of law, when buying gasoline, taking an airplane or using electricity. The card contains your yearly carbon ration to be drawn down with every purchase, every trip, every swipe.

There's no greater social power than the power to ration. And, other than rationing food, there is no greater instrument of social control than rationing energy, the currency of just about everything one does and uses in an advanced society.

So what does the global warming agnostic propose as an alternative? First, more research — untainted and reliable — to determine (a) whether the carbon footprint of man is or is not lost among the massive natural forces (from sunspot activity to ocean currents) that affect climate, and (b) if the human effect is indeed significant, whether the planetary climate system has the homeostatic mechanisms (like the feedback loops in the human body, for example) with which to compensate.

Second, reduce our carbon footprint in the interim by doing the doable, rather than the economically ruinous and socially destructive. The most obvious step is a major move to nuclear power, which to the atmosphere is the cleanest of the clean.

But your would-be masters have foreseen this contingency. The Church of the Environment promulgates secondary dogmas as well. One of these is a strict nuclear taboo.

Rather convenient, is it not? Take this major coal-substituting fix off the table and we will be rationing all the more. Guess who does the rationing?

Charles Krauthammer is part of The Washington Post Writers Group. Reach him at letters@charleskrauthammer.com.