WASHINGTON – Last week I got involved in one of those arguments that can happen only in Washington. It began innocently enough, with an attempt to ascertain whether the executive branch of the American government has the right to set fuel mileage standards – corporate average fuel economy standards, in Washington speak – for cars. While touring Biloxi, Miss., President Bush had declared that he would like Congress to “give me a capacity to raise CAFE standards.” That implied, of course, that Bush could not require manufacturers to produce more fuel-efficient cars unless Congress allowed it.

On the face of it, this seems odd. Certainly the president had such a capacity in the past, since these requirements were changed a couple of times in the 1980s. Certainly Congress was under the impression that the president could require cars to get better mileage in the 1990s, since it went out of its way, using annual spending legislation, to prevent President Clinton from doing so. So I asked someone in Congress and someone in the White House to clarify.

Boy, was I sorry. Marshaling their lawyers, their experts and all of their vast institutional knowledge, both set out to prove their point. Zing! Here’s Title 49, United States Code, Subtitle VI, Part C, Chapter 329, which shows that the administration needs congressional approval to require that cars get more than 27.5 miles per gallon. Ka-ching! Here’s a copy of Fed. Reg. 2912 n.2 (Jan. 22, 1986), which shows that the Reagan administration believed it did not need congressional approval to change fuel economy standards. Zap! Here’s a D.C. Circuit appeals court ruling that authorizes the Transportation Department to modify fuel standards. Bam! Here are quotes from the Transportation Department Web site that seem to prove both points simultaneously.

Although it was hard to say who really won, at least one indisputable conclusion did emerge: Neither the president nor Congress nor anyone else has really been interested in this subject for about 30 years, and particularly not for the past five. That isn’t to say individuals haven’t tried to change the standards; year in and year out some senator plaintively tries to add a CAFE measure to an energy bill. But the political culture, on the whole, hasn’t supported it. Politicians from Michigan oppose higher fuel economy standards because the automakers say their costs will go up. Politicians from rural areas oppose gas taxes – the logical, simpler alternative to fuel economy standards – because they hurt their constituents most. Politicians from Alaska push more oil drilling in lieu of an energy policy. Politicians from everywhere helped write laws that resulted in no policy at all.

But the consumers, who are also voters, have helped, too. The truth is that the advantages of big, gas-guzzling cars have, at least until recently, been large. Big cars are convenient. They are comfortable. They use more gas, but gas, even at $3 a gallon, is still historically cheap when you adjust for inflation. They feel safer – bigger, wider – even if they aren’t. They make it possible to live on larger plots of land, farther away from smog. Above all – and this is the factor too many analysts overlook – they make it easier to transport large numbers of children. Speaking as someone whose car can hold only three small children in car seats (or four large children with one in front), I can testify to the fact that my car is inadequate to the requirements of the modern, four-family carpool. The fear that she’d be left out of the four-family carpool in her neighborhood recently inspired a friend to ditch her compact for a new sport-utility vehicle that seats seven.

By contrast, the arguments against big cars are either very long-term, very diffuse or involve places very far away. In daily life, one isn’t really affected by climate change that will take place sometime in the next century, or by the fact that petro-dollars are being used to build radical mosques in London. Fear that high oil prices increase the power of nasty dictators in the Middle East or South America isn’t something that easily computes into the average SUV buyer’s decision-making.

Breaking the logjam – convincing Americans that it’s in their real interest to buy fuel-efficient cars, or forcing manufacturers to make them, or forcing everybody to pay higher prices for fuel, or creating a distribution system for alternative fuels – will require more than a he-said, she-said exchange between Congress and the White House, more than a tiff between political parties, more, even, than a bit of fingerpointing at oil companies or SUV drivers. What is needed is not just an economic but a political change, even a cultural change. But do we have a political class capable of carrying it off?