Politicians say some really stupid things, and most people, including interviewers on TV are unaware of it. For example, Democrats are currently saying that it would do no good in terms of reducing gasoline prices to drill for more oil, or to develop shale oil, etc. because it would take ten years for the new oil to reach the market. (This is not true, but never mind that.) Instead the Democrat's want to implement new higher automobile gas mileage requirements. The Democrats seem oblivious to the amount of time it would take for higher mileage standards to reduce gasoline consumption. It takes three or four years to design the higher mileage cars and get them to market. Then, consider that there are about 250 million cars on the road in the USA, with about 17 million new cars coming on the road each year. So, it would take at least 17 years to replace the entire fleet. (I assume that not even the Democrats want to just destroy all of the existing cars representing about $2.5 trillion in capital; but, on reflection, maybe they do.) Obviously it will take a long time for the higher mileage cars to make a significant reduction in fuel consumption.

Another question that no one asks is this: the two courses of action are not mutually exclusive, so why don't we both improve mileage and increase supply?