One of the easiest "fixes" is to redo CAFE standards/law and remove the "two fleet" rule.

"Nor would it have to repeal the CAFE rules that are now a sacred cow. It would simply have to allow auto makers to meet the fuel economy standards with any mix of autos made in domestic or overseas factories.

Under the nonsensical "two fleet" rule that now applies, manufacturers meet the standards separately with their "domestically" and "nondomestically" produced fleets. What does this have to do with making sure U.S. consumers get good mileage? Nothing. It's a naked handout to the UAW at the expense of the companies and their customers."

The entire article can be found here. It is a free read.

http://online.wsj.com/article/SB122584326266699163.html

High-efficiency diesel ...

I could only support new diesel applications if we can save a comparable volume of diesel fuel from other apllications. The reason is that the relative amount of diesel versus gasoline (and other distillates) is largely invariant (i.e. we can't change it much), and diesel is already in relative scarity. So while diesel engines are thermodynamically more efficientl than say gasoline engines, overall the relative consumption of the two fuel types cannot vary by much. Even without created new diesel demand in the car market, demand reduction for diesel is more important for the overall system balaance than demand reduction for gasoline.

Now, if we can aggressively reduce diesel demand, by such actions as improving trucking aerodynamics, electrifying trains, producing hybrid construction equipment, and buses etc, then perhaps we can free up enough diesel to pursue your solution.