I personally don't think that idea is the answer to the problem.

I don't see gas prices really affecting the distances or frequency that people drive, especially in the US. A significant, sustained increase in gas prices may affect which cars people purchase though. The US has been on a 10-year SUV craze. Maybe the fad will change and everyone will be driving diesel wagons in the near future. They can be the soccer-mom car for the 2010's. All we need now is someone to make it cool. Are you listening Leonardo?

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Profeshenal spellar