The average U.S. price for a gallon of gas is $3.144, down about 20 cents from a year ago, reports AAA. They’re paying $2.87 in Missouri, according to, and eight states are below the magical $3 a gallon. Great, right? Actually, no.

gas price chart

Here’s why low gas prices are bad:

1. They encourage more driving. We measure America on wheels through a metric called Vehicle Miles Traveled (VMT), and VMT was on a steady rise in the postwar period until around 2004, when it reached a likely peak and began to decline. High gas prices (along with congestion) discouraged driving. Remember the $4-a-gallon gas that went along with the 2008 recession?

2. They discourage green car buyers. There’s a straight line between interest in green cars, especially electrics, and high gas prices. I wrote in 2011, “When gas prices drop below $3 a gallon, consumer interest in fuel economy wanes.” According to Consumer Reports, “In a troubled economy, with gas prices relatively low, green in the wallet trumps environmental concerns for many.” There’s another way of looking at it, though, electrics cost 3 cents a mile to drive, and gas cars at least 12 cents. That argument would get further if EVs and hybrids didn’t cost more.

A gas station in Henderson, Nevada in the late 1980s.

This is what they paid for gas in Henderson, Nevada in the late 1980s. Yes, that's 89 cents a gallon — and they probably thought it was high at the time. (Photo: Roadside Pictures/flickr)

3. They cause more smog. According to the Federal Highway Administration, Los Angeles residents drive an average of 23 miles per day, compared to 17 miles in New York (where almost half the people don’t own cars). In 2012, the average Angeleno (now encountering more congestion than ever, due partly to lower gas prices and the improving economy) wasted 59 hours in traffic, and breathed some of the worst air in the U.S. In 2013, LA topped the American Lung Association’s air quality report card for ozone pollution, aka smog. Reports Reuters, “A major source of ozone pollutants is tailpipe emissions from automobiles, which in turn account for Los Angeles' No. 1 ranking this year as the nation's most traffic-clogged city.” Cheaper gas makes the problem worse, and of course it mightily aggravates global warming, which could be a sixth bullet point.

This traffic jam is in Miami, but it could be anywhere in major metro America.

This traffic jam is in Miami, but it could be anywhere in major metro America. (Photo: jose/flickr)

4. They lead to more accidents. High gas prices discourage driving — people take transit if it’s available instead, which is why transit rides are up sharply. But let’s take a step back. Remarkably, although the number of cars on the road is up, annual traffic deaths in the U.S. has held steady — thanks to much safer cars, with equipment such as traction control, multiple airbags and lane departure warnings. In 2012, the most recent year for which I have data, there were 33,561 deaths, about the same as 1940, when there were only 132 million Americans (now there are 319 million). “A state’s population has an obvious effect on the number of motor vehicle deaths,” says the Insurance Institute for Highway Safety, but VMT is even bigger. It’s fairly simple math: Put more cars on the road, even safer ones, and the statistics will tick up.

5. They support the bad guys. It’s not just Al Qaeda. It's ISIS, too. This is from Business Insider last month: “In an oil field in northeastern Syria, trucks line up daily to load crude sold cheaply by Islamic State militants who have hijacked parts of the country’s energy industry in their bid to build a caliphate.” And this from Reuters last July: “The UN Security Council expressed grave concern on Monday over reports that radical militants have seized oilfields and pipelines in Syria and Iraq and warned that anyone caught trading in oil from the ‘terrorist groups’ could face sanctions.” The U.S. imports only 33 percent of its oil now, the lowest amount since 1985, but we’re still buying a ton of it from the Middle East. Saudi Arabia is our second-largest oil trading partner.

Are oil companies manipulating the price to keep us addicted to oil? No smoking gun here, but cheap gas is a smart Big Oil strategy right now. If you doubt the equation between low gas prices and more driving, just watch this video, in which a happy motorist says, "Gas prices go down and I'm hitting the road!"

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Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.