Washington ? In today’s segmented America, Michael Crichton’s new novel, “State of Fear,” might seem to be just reading for red states. Granted, a character resembling Martin Sheen — Crichton’s character is a prototypical Hollywood liberal who plays the president in a television series — meets an appropriately grisly fate. But blue states, too — no, especially — need Crichton’s fable about the ecology of public opinion.

“State of Fear,” with a first printing of 1.5 million copies, resembles Ayn Rand’s “Atlas Shrugged” — about 6 million copies sold since 1957 — as a political broadside woven into an entertaining story. But whereas Rand had only an idea — a good one (capitalism is splendid), but only one — Crichton has information. “State of Fear” is the world’s first page-turner that people will want to read in one gulp (a long gulp — 600 pages, counting appendices) even though it has lots of real scientific graphs, and footnotes citing journals such as Progress in Physical Geography and Transactions — American Geophysical Union.

Crichton’s subject is today’s fear that global warming will cause catastrophic climate change, a belief now so conventional that it seems to require no supporting data. Crichton’s subject is also how conventional wisdom is manufactured in a credulous and media-drenched society.

Various factions have interests — monetary, political, even emotional — in cultivating fears. The fears invariably seem to require more government subservience to environmentalists, and more government supervision of our lives.

Crichton’s villains are environmental hysterics who are innocent of information but overflowing with certitudes and moral vanity. His heroes resemble Navy SEALs tenured at MIT, foiling the villains with guns and graphs.

The villains are frustrated because the data do not prove that global warming is causing rising sea levels and other catastrophes. So they concoct high-tech schemes to manufacture catastrophes they can ascribe to global warming — flash floods in the American West, the calving of an Antarctic iceberg 100 miles across and a tsunami that would roar at 500 mph across the Pacific and smash California’s coast on the last day of a Los Angeles conference on abrupt climate change.

The theory of global warming — Crichton says warming has amounted to just half a degree Celsius in 100 years — is that “greenhouse gases,” particularly carbon dioxide, trap heat on Earth, causing … well, no one knows what, or when. Crichton’s heroic skeptics delight in noting things like the decline of global temperature from 1940 to 1970. And that since 1970 glaciers in Iceland have been advancing. And that Antarctica is getting colder and its ice is getting thicker.

Last week Fiona Harvey, the Financial Times’ environmental correspondent, fresh from yet another international confabulation on climate change, wrote that although the Earth’s cloud cover “is thought” to have increased recently, no one knows whether this is good or bad. Is the heat-trapping by the clouds’ water vapor greater or less than the sun’s heat reflected back off the clouds into space?

Climate-change forecasts, Harvey writes, are like financial forecasts but involve a vastly more complex array of variables. The climate forecasts, based on computer models analyzing the past, tell us that we do not know how much warming is occurring, whether it is a transitory episode, or how much warming is dangerous — or perhaps beneficial.

One of the good guys in “State of Fear” cites Montaigne’s axiom: “Nothing is so firmly believed as that which least is known.” Which is why 30 years ago the fashionable panic was about global cooling. The New York Times (Aug. 14, 1975) saw “many signs” that “Earth may be heading for another ice age.” Science magazine (Dec. 10, 1976) warned about “extensive Northern Hemisphere glaciation.” “Continued rapid cooling of the Earth” (Global Ecology, 1971) could herald “a full-blown 10,000 year ice age” (Science, March 1, 1975). The Christian Science Monitor reported (Aug. 27, 1974) that Nebraska’s armadillos were retreating south from the cooling.

Last week, The Washington Post reported that global warming has caused a decline in Alaska’s porcupine caribou herd and has lured the golden orange prothonotary warbler back from southern wintering grounds to Richmond, Va., a day earlier for nearly two decades. Or since global cooling stopped. Maybe.

Gregg Easterbrook, an acerbic student of eco-pessimism, offers a “Law of Doomsaying”: Predict catastrophe no later than 10 years hence but no sooner than five years away — soon enough to terrify, but far enough off that people will forget if you are wrong. Because Crichton remembers yesterday’s discarded certitudes, millions of his readers will be wholesomely skeptical of today’s.

— George Will is a columnist for Washington Post Writers Group.