President Bush has signed a new "fuel efficient" energy bill, and the chattering classes are weighing in. Some are seeing the gas tank half-full, some half-empty. The tongue-cluckers believe the bill is all "show" and no "go," that it will not only do little to stem the flood of gasoline, but will let politicians off the hook so they can crow about the legislation without having to act on more meaningful energy reforms.

The sunnier observers feel a drop in the bucket is better than nothing. And though the bill is a symbolic gesture, it is an important symbol.

In short, the bill calls for a big increase in the use of ethanol as a motor fuel and requires companies to make cars, SUVs and small trucks that will get 35 miles per gallon by 2020. Refineries also must increase their use of ethanol. Democrats say the bill will eventually save motorists $700 to $1,000 a year in fuel costs. Naysayers say the public will simply drive more when they find they are saving more.

But amid the bickering, the only ones who can really drive fuel efficiency home, of course, are the American voters — not just by voting for candidates who favor burning less petroleum, but by turning the tide and making gross waste a social faux pax. That is what happened with recycling. There was a time when no one recycled cans and newspapers, but now the scowls when someone tosses soda cans in the garbage instead of the recycling bin keep most people on their toes. The same with tobacco. Once secondhand smoke became a public health issue, "smokers rights" went out the window in a big puff.

Eventually, the same might be said of driving fuel efficient vehicles. So far, there has been a bit of a backlash against "gas guzzlers," but nothing that undermines the status of driving a $20,000 machine. In time, however, when wasting fuel becomes a true stigma, attitudes will adjust.

Whatever real effects the new energy bill has on consumption, just the fact it passed with such fanfare makes it a worthwhile symbol for a society that can't seem to kick the petroleum habit.