For all the talk about the Gusher in the Gulf, one fact has received remarkably little attention: the relatively small part of our oil consumption that's met by offshore drilling. The U.S. consumes about 5.2 billion barrels of oil a year (about two-thirds imported) with about 530 million barrels produced through U.S. offshore drilling - in the Gulf of Mexico, off the West Coast, and in Alaska. In other words, only about 10% of the oil we consume each year comes from wells drilled off the U.S. coast. Or, to put it another way: We could shut down every U.S. offshore well -- if we could, in fact, shut them down -- and not feel the loss if we would just cut our oil consumption by 10%.

10% isn't so much to ask, is it? I had this thought in mind while planning a trip from from Madison, Wisconsin to visit my mom in Urbana, Illinois, a drive along 270 miles of some of the least-scenic highway in the United States (On your left: corn, beans, beans, corn. On your right: beans, corn, corn, beans.) I'd complained as loudly as anyone about BP's criminal negligence, I'd seen the pictures of oil-coated sea birds, but was I willing to change my own oil-consumption habits in response?

A little research confirmed that if I simply cut my highway-driving speed from my usual 70-75 mph (I really hope no one from the Illinois Highway Patrol is reading this) to a Jimmy-Carteresque 55 mph, I could reduce my fuel consumption by 15% or more, enough to eliminate my share of the dirty and dangerous 10% we get offshore.

Before my trip, in an attempt to communicate a message (and also to keep myself honest) I taped a single four-foot-long bumper sticker over my trusty "Wisconsin Green Party" and "Bring Our Troops Home" bumper stickers. In large black letters on a bright construction-zone-orange background, it said:

55 mph = 15% less gas used = no offshore drilling needed

I then pointed my 21 year old Honda Accord southward, and committed myself to six hours of life in the slow lane. I have no dramatic experiences to report, no one tried to run me off the road or even sent a rude gesture my way. Hundreds and hundreds of cars and trucks passed me (a pointer for those who want to communicate by car bumper: more people see your message if you go much slower than the prevailing traffic.) On the other hand, no one pulled in behind me and decided to join in my 55 mph crusade, except for a couple of stretches when we were all slowed to 55 for road construction (Thanks for the helping hand, Illinois Department of Transportation!) and one long convoy of camo-painted Humvees, likely from the Illinois National Guard, who followed me down I-74, speed-limited under some obscure military regulation (Or could it be that soldiers who've fought in our oil wars know better than most the true cost of a gallon of fuel?)

Here are the numbers: 270 miles on 6.9 gallons of gas, or 39 miles per gallon. That's 22% better than the 32 mpg I usually get on my Madison-Urbana route.

Of course, the oil-consumption story is a bit more complicated than an equation on a big orange bumper sticker. About two-thirds of U.S. oil consumption is used for transportation, so we'd really need to cut all transportation use by 15% to get a 10% overall cut in consumption. And what percentage of transportation use is personal automobile transportation, as opposed to shipping, public transportation, and air travel? A good estimate can be gotten by noting that about three-fifths of transportation fuel sold is gasoline (as opposed to diesel or aviation fuel). Neglecting the relatively small number of diesel cars, let's take 60% as the share of oil consumption from personal cars, SUV's, etc. This class of drivers would actually need to reduce their fuel consumption by 25% to eliminate the need for those 530 billion barrels per year of offshore oil.

No, that's not going to come from just slowing to 55, but you already knew that, didn't you? Lots of things need to happen if we're going to break our national oil addiction and limit the damage from catastrophic climate change (reducing the average 1500 miles that the average meal travels from farm to plate, for example.) Right now, I'm imagining a solution in which "slow food" meets "slow cars." The Farmer's Market, Community Supported Agriculture, a garden, and something new, for me: I'm keeping my big orange bumper sticker and joining the "drive 55" movement.