It's a truism of new-car sales: Gas prices go up, buyers focus more on gas mileage. Gas prices go down again, people forget all about fuel efficiency.

Well, here's a gentle reminder about why you may want to focus on cars with high EPA ratings for gas mileage.

As The New York Times reported, on Tuesday a senior Iranian government official said the country would retaliate against proposed U.S. sanctions on the country by closing the Strait of Hormuz, the bottleneck through which roughly one-fifth of the world's oil supply is shipped.

The strait has long been viewed as a possible choke point for oil shipments. It sits between Iran on the north and the United Arab Emirates to the south.

Energy security experts have proposed that either barricading the strait, as Iran threatens, or--even worse--sinking one or more ships in it could throttle the globe's continuously growing appetite for crude oil.

And THAT would likely cause oil prices to soar, at least for a while. Which would, in turn, boost gasoline prices by unknown amounts.

Because, while U.S. gasoline consumption peaked five years ago and is now falling, U.S. drivers are still subject to global oil prices--no matter how much or how little gas they consume.

Meanwhile, Iran has racheted up its threats, the Times said yesterday, with Iranian rear admiral and naval commander Habibollah Sayyari saying on Press TV, an official news site for the country, that, “Closing the Strait of Hormuz is very easy for Iranian naval forces."

He also claimed that his country "has total control" over what he rightly termed a "strategic waterway."

So if you're in the market for a car, you may want to consider buying the model that meets your needs best--and has the highest EPA rating among your options.

Gas pump

Gas pump

Need a crossover or tall wagon, for example? Over the long weekend, we're testing the 2012 Toyota Prius V wagon. It's rated at 44 mpg city, 40 mpg highway, for a combined EPA rating of 42 mpg.

We're consistently getting 40 mpg so far, including hauling heavy boxes over hilly terrain at high speed (not a hybrid's most favorable duty cycle).

Iran may not make good on its threat. The country may just be posturing to delay or avert U.S. sanctions on its oil exports.

And the world's petroleum supply system will, sooner or later, find alternatives and ways to "route around the damage," as computer systems architects say.

It's just that you have no idea what gasoline will cost next week, next month, next year, or over the life of your car. You can guess, of course, as we all do. But .... what if you guess wrong?

We're just sayin'....


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