The auto industry (and the senators from Michigan) continue to do one thing and say another about trying to improve the sustainability of their products.

The usually politically-neutral Popular Mechanics has weighed in, pointing out the inconsistency between auto companies saying they'll do something about greenhouse gas emissions and their opposition to CAFE standards and California's tough emission standards.

While CAFE isn't the only path to controlling emissions, using less fuel per mile is the most direct way to more sustainable motor vehicle transportation. The auto industry is paranoid that if cars cost a few thousand more dollars per year that people would stop buying, but that is simply not true. Thousands of premium cars are sold every day that provide additional power, and a growing audience of consumers car about their carbon footprint. It's another feature.

Also, unlike adding horsepower or torque, fuel efficiency puts money back in their wallets, and rising gas prices only increase the attractiveness. While I'm a firm believer in the free market, the auto industry has been limiting choice for decades -- try to for a family-sized vehicle that gets better than 35 mpg. Unfortunately legislation is needed because the auto industry has been resisting a necessary change for decades.

A bill in the senate would deprive the states of the ability to regulate emissions for autos. States should continue to have this right because forward thinking states recognize the benefits of cleaner-burning vehicles to their citizens and economies.