When the dog actually caught the bus

Short Answer: Next time Dems are in charge, implement a tailpipe CO2 emission limit, like we do for other pollutants. I believe with the SCOTUS decision that CO2 is a pollutant under the Clean Air Act, the President could do this unilaterally via regulation. Automakers had their chance to work collaboratively to combat climate change and they spurned it. Now they get the stick.

 

The amount of emitted carbon dioxide is directly tied to the amount of fuel burned. The measuring of CO2 from the tailpipe during emission testing is how they measure the amount of fuel used.

That would be no different a fuel economy limit with added complications. The emission bin ranking system for passenger cars is not tied the vehicle weight or size; it would have to be for CO2 for this to have a chance of working.

The CAFE system does work. The fault is in the fact that there is no incentive for car buyers to get efficient cars. Gas prices go down, and they go back to less efficient cars. Then the car companies have to buy CAFE credits from another company, or deeply discount their efficient offerings. If meeting CAFE didn't directly hurt their profits, they wouldn't fight it as hard.

PS: One critique of the article. It made some basic mechanics of how CAFE always worked sound like it Obama was responsible for.