SIOUX CITY, Iowa -- Richard Gephardt tours the frozen steppes of Iowa in a metaphorical $48,000 Chrysler K car -- what he says that humble American vehicle would cost in South Korea after it's customized by tariffs. It's an outlandish car, sporting tariffs and fees, flying a foxtail of Yellow Perilism, protectionism and just plain rank politics. Nevertheless, it's taken Gephardt a long way.

The nonexistent car clearly strikes a chord here in Iowa -- and drives Gephardt's Democratic rivals to distraction. There is nothing they hate as much as the ridiculous K car -- an automotive cheap shot, a political simplicity, but a telling metaphor for the economic anxiety that is felt across America. Gephardt has introduced something new into the Democratic presidential contest: unabashed politics.

On the face of it, the Gephardt argument is both facile and ridiculous. His K car may well cost $48,000 in Korea, but even if it were stripped of its fees and tariffs and sold in Korea at $10,000, it's not likely Koreans would buy it. Off the stump, Gephardt concedes as much. He has always said that America's competitive problems are internal -- that tariff barriers represent less than 20 percent of the trade deficit.

But on the stump, it's a different matter. Here the car is tooled out in all its repugnant glory, and Gephardt vows revenge. As president he would force the Koreans to lift their tariffs on American cars or face the consequences for their Hyundai: ''If they refuse, they are going to leave the table wondering how they are going to sell a Hyundai in America for $48,000 a car.'' The line brings down the house.

Protectionism? Yes. An answer to America's trade problems? No. But an example of imaginative political packaging? Yes. The other candidates talk the language of economic crisis -- the federal deficit, the stock market collapse or, here, the plight of the family farmer. Yet the fact remains that America is not in crisis.

Seven years of Ronald Reagan has left American politicians bereft of hard, emotional issues. The nation is not at war. There is nothing to match the Watergate scandal, soaring inflation -- not even a missile gap, real or otherwise. The federal budget deficit is a concern, but not -- it seems -- an immediate threat, and the trade deficit is humbling but almost an abstraction. Unemployment, after all, is only 5.8 percent.

What there is, though, is unease -- a sense that standards of living are slipping. It's harder and harder for young people to live as well as their parents did or do. Home ownership is on the decline for the first time since the 1930s. Employment figures are high, but the well-paying blue-collar jobs of heavy industry have been replaced by those in service industries -- lower paying and often part-time.

Young people know that something is wrong, but so do older people. And the American automobile, once supreme and unassailable, has come to represent the American malaise. Imports rule the road -- everything from the utilitarian Toyota to that favorite of the fern bar, the BMW. Down this road, horn blaring, comes the Gephardtmobile -- a stark metaphor for what used to be and what is now manifestly wrong.

Whether the tactic will work for Gephardt remains to be seen. But he has taught the other candidates a lesson. Massachusetts Gov. Michael Dukakis, for instance, said in an interview that Gephardt has simplified the complex trade issue. It is not in Dukakis' nature to simplify anything, and he has the expert's disdain for the amateur.

But Dukakis has yet to learn how to boil down his own message -- how to concoct the theme that will strike a chord in Americans. A measure of Dukakis' problem is that the ultimate charge against him is that he's a technocrat -- a manager of details.

The issue-less nature of the Democratic race explains why, at the moment, Gephardt, Dukakis and Paul Simon are bunched so close. The last two are the Grand Tinkerers of the campaign. They have programs galore but no overriding theme. A Gephardt campaign worker tells the tale of Iowa. She was originally for Simon, moved to Gephardt, but reports her mother has gone the other way -- to Simon.

The first time I saw Gephardt use the trade issue on the stump was months ago in New Hampshire. It seemed to work there, and it has worked here too. Back then, Gephardt toured New Hampshire in a vintage Studebaker. He's replaced it with the $48,000 K car. Soon, most of the Democratic candidates will be driving one.