But at the same time, the Democrats are pushing their cap-and-trade scheme -- the Waxman-Markey climate bill -- through Congress, and it surely won't work.

The Apollo engineers' motto was "Waste anything but time." Waxman-Markey seems to do that one better, promising to waste everything, including time. It's a legislative blunderbuss that fails any remotely honest cost-benefit analysis, as Jim Manzi painstakingly demonstrates in the current issue of National Review. Under the bill, the government would sell or give away waivers -- call them ration cards -- for carbon emissions, worth tens of billions of dollars. The system is destined to become politicized. Waivers will be granted to favored industries and donors in states with political clout.

If everything worked exactly according to plan, it would cost the economy trillions of dollars over the coming decades. Meanwhile, climatologist Chip Knappenberger -- administrator of the World Climate Report, an avowedly global-warming-skeptical blog -- uses standard climate models to show that the payoff would be to reduce global temperatures by about 0.1 degree Celsius by 2100. Sponsors of the legislation haven't offered a competing analysis.

"The costs would be more than 10 times the benefits," writes Manzi, "even under extremely unrealistic assumptions of low costs and high benefits." All the while, China, India and other countries are simply scoffing at the suggestion they curtail their carbon emissions.

Now, I am more skeptical about the threat of global warming than Manzi is, never mind the Al Gore chorus. But let us assume the chorus is right and it is the moral equivalent of a war for our very survival as a civilization. The question remains: Why? Why this approach? Why see global warming as an excuse to expand government regulation and taxation rather than invest in problem-solving?

The U.S. government could spend trillions on research into scrubbing carbon from the air, bioengineering organisms to eat greenhouse gases or crafting substances to reflect more heat back into space. We could establish prizes for development of long-life batteries or clean coal technologies. And if any of these investments paid off, decades from now the benefits would still dwarf Waxman-Markey at a fraction of the cost. It hardly takes a rocket scientist to see that.