At last, conditions appear almost ideal for Congress to demand substantially greater fuel efficiency from cars and light trucks.
Longtime advocates of such policy are in power, foreign and domestic sources of oil are increasingly fragile, evidence of transportation's role in global warming is indisputable and the average pump price of gasoline is creeping again toward $3 a gallon.
Yet overcoming the combined resistance of automakers and autoworkers and their congressional allies in both parties remains difficult. Democratic leaders, who control the agenda, should declare breaking this two-decade-long stalemate a top priority.
Auto executives, led by Detroit's Big Three, are singing for Congress their same old song about why requiring better fuel efficiency would be ruinous to the industry: Changing technology costs too much; jobs would be lost; cars would have to be smaller and less safe; no one will want them.
But Detroit's failure to move aggressively on its own with the available technology to develop cars and small trucks that are sporty, practical and able to get 35 miles or more on a gallon of gas is what has all but ruined the U.S.-based industry. It can't match foreign competitors. Mandates from Washington might be all that can save Detroit at this point.
It's encouraging that fuel efficiency proposals are sprouting up all over Capitol Hill, some from unlikely sources, including President Bush. The most promising plan so far is that offered by Massachusetts Democrat Edward J. Markey, who would demand a 4 percent increase in fuel efficiency annually up to a per-gallon goal of 35 miles, from the current 24.9, by 2018 - a target scientists say can be met without resorting to half-electric hybrid engines. After 2018, annual increases would be required if the technological improvements are within reach.
Mr. Bush's plan is based on a similar 4 percent annual increase, but it does not contain any specific target and leaves it up to the National Highway Traffic Safety Administration to design the regulations.
Most threatening to the enactment of meaningful legislation is the regional coalition of lawmakers whose districts include autoworkers, making them more susceptible to threats that jobs will be lost. Chief among those is Rep. John D. Dingell, a Michigan Democrat who chairs the House committee with the most influence over the issue.
Even so, for the first time since 1975, when Congress last imposed fuel efficiency standards, the moment for updating them may have arrived. Mr. Markey has offered versions of his bill for six years straight, picking up more support each time, until last year when the Republican-led House wouldn't take a chance on allowing it a vote.
Automakers would be smart to embrace the move toward cleaner, lower-cost cars and help Congress save them from themselves.