Washington ? Markets are mechanisms for generating and disseminating information. The term “market failure” denotes instances when markets behave inefficiently, preventing optimal outcomes because of barriers that prevent new products from competing, or because consumers receive insufficient info about competing products. Iowa’s political market, called caucuses, where barriers to entry were negligible and information was abundant, worked well.

Like some other American arrangements (e.g., the Electoral College, judicial review), no deliberation planned Iowa’s system to function as it now does. But Monday night the nation’s vetting of Democratic candidates began efficiently because a critical mass of information about Howard Dean, most of it impulsively and imprudently supplied by him, had reached that state’s Democratic consumers. They responded by slowing the slide of the world’s oldest party toward nominating a political novelty unsuited to the national market.

Dean is a problematic product because the fuel that launched his rocket — a combustible brew of anger, pugnacity, moral vanity and intellectual condescension — severely limits the apogee of his trajectory. Television enforces intimacy with candidates and presidents — they are in America’s homes nightly. Many intense Democrats have had the fun of picnicking on Dean’s ideological red meat but are now flinching from the prospect of having, or of asking less-partisan Americans to have, prolonged intimacy with Dean’s sandpapery personality and equally abrasive agenda.

Gratuitously abrasive. Not only does he promise to raise middle-class taxes, he breezily acknowledges that because of his protectionism, “prices will go up at your local Wal-Mart.”

The evidence from Iowa is sobering news for the White House. It is that the Democratic nominating electorate is serious about replacing George W. Bush. It understands that, come November, there would be many more Bush Democrats than Dean Republicans. In 2000, only about 10 percent of Democrats voted for Bush. Dean would be the Democratic nominee most apt to drive up that number.

In 1964, Goldwater supporters had the theory of “conservatives in the woodwork.” It was that millions of potential Republican voters stayed home in presidential elections because the conservatism of Republican nominees was too tepid. Offer “a choice, not an echo” and voters would pour out of the woodwork. They did not in 1964. But this year Dean’s theory is — was — that lots of liberals are lurking in the woodwork, waiting for a candidate as furious as they supposedly are.

Dean will not get to test his theory in November, because the future is like the past only up to the time when it isn’t. In the last five presidential elections, since 1984, the candidate with the most money in the year before the election won the nomination. Last year that was Dean. But the Edsel was backed by all the marketing muscle of the Ford Motor Co.

Iowa severely damaged the angriest candidate, Dean, who led there almost until the moment it mattered. Iowa destroyed the oldest candidate, Dick Gephardt, 62, winner of the 1988 caucuses.

Gephardt, the last practitioner of Franklin Roosevelt’s politics, is a good man and gallant campaigner. But because of the expansion of the middle class and social security — the condition, not the program — that FDR accelerated by means of broadened unionization, home ownership and Social Security, the blue-collar core of Gephardt’s support is too small a lever to move an election.

The growing, aggressive portion of organized labor consists of white-collar government workers — government as interest group, another New Deal legacy. They never warmed to Gephardt, but will have no trouble shifting to Kerry, or to the sunniest candidate — John Edwards, the unDean, all smiles and no snarl.

Wesley Clark, who did not discover his Democratic allegiance until last September, is another matter. Clark awaits in New Hampshire. But with two real Democrats, Kerry and Edwards, showing strength — one of them with serious foreign policy and military experience — what rationale remains for Clark’s candidacy?

Kerry and Edwards, two of the Washington “cockroaches” that Dean disdains, together won nearly four times Dean’s vote. His anti-Washington rhetoric would seem stale and puerile even among mainstream conservatives, who have long since come to terms with the fact that Americans want to augment Washington’s power to assuage two of life’s great fears — illness and old age.

Because Americans of all political persuasions demand vital and complex services from Washington, Clark, the next novelty to receive tardy scrutiny, will face doubts of the wisdom of treating the presidency as an entry-level political job. Now he has most to fear from the fact that the market generating and disseminating political information is working efficiently.

George Will is a columnist for Washington Post Writers Group.