Aye. There's the rub.

I heard a few years ago that the main reason for the boom is SUV's was the Gas guzzler tax in California. Cars were taxed extra based upon gas consumption and truck and SUV's were not. Therefore consmers and manufacturers flocked to trucks and SUV's. A 5,000 pound SUV is still going to consume more fuel in driving and more materials in the construction than a 2,500 pound car. If America were to encourage more people to switch to fuel efficient cars as of today. It would still loose out because foreign companies dominate the low end of the market. Jobs would be exported the economy would suffer. Switch to public transport? Almost impossible to do with the current infrastructure and lifestyles in spread out Cities like LA , in the smaller cities and in the suburbs.

It would take a complete change in outlook for millions of people. Can the government legislate this? Can they commit to it in international treaties?