Jeff Jacoby

LATE LAST MONTH, President Obama announced new automobile fuel-efficiency standards that will require cars to achieve an average of 54.5 miles per gallon by 2025. Vehicle fleets currently average 27 miles per gallon, so the new target would boost fuel efficiency by an unprecedented 100 percent within 14 years. But barring an engineering miracle, that's probably pie in the sky. After all, from 1975, when the first federal mileage rules for new cars were enacted, it took more than 30 years to improve automobile efficiency by just 60 percent. And the easy gains were achieved early on; since 1980, fuel economy has climbed by only about 1 percent a year.

In truth, there is less to the new standards (known as CAFE, for corporate average fuel economy) than meets the eye. Writing for The Hill, John German of the International Council on Clean Transportation, a former Chrysler powertrain engineer, points out that "automakers will be graded on a curve." That means "an automaker that builds mostly larger cars, SUVs, and trucks will have lower mileage goals than a competitor that builds mostly compact and subcompact cars."

A mandate of 54.5 mpg may generate arresting headlines, but down in the fine print, the numbers aren't nearly as striking. "Even if the auto industry manages to meet the new standards," reports The New York Times, "it is unlikely car buyers will see many fuel-economy stickers with such high mileage." Thanks to an array of "credits," discounts, and testing procedures built into the CAFE system, 54.5 mpg will really be more like 40."It is unlikely car buyers will see many fuel-economy stickers with such high mileage

But the fuzzy mileage numbers aren't nearly as dubious as the endlessly repeated claim that greater fuel efficiency will mean lower fuel consumption, and in turn reduce American dependence on foreign oil.

"This agreement on fuel standards," declared the president at his CAFE press conference, "represents the single most important step we've ever taken as a nation to reduce our dependence on foreign oil. Think about that."

Jeff Jacoby

Jeff Jacoby is an Op-Ed writer for the Boston Globe, a radio political commentator, and a contributing columnist for