It was entirely political. You will remember that Ronny Reagan took over after Carter. One of the first things he un-did was to repeal the gas mileage standards Carter had set in place back in 1976. By now, if they were left in place, we should all be getting at least 40 mpg. in every car produced. The big auto manufactures and the oil companies didn't like that. So here we are, 30 years later, getting 20 mpg, or only 10 on a F350 dualie-diesle. Seen all the Mom's in Hummers in the school pickup lines? Brilliant.