This is not a suggestion. This will happen. Full story here.
The Obama administration announced strict new fuel-efficiency vehicle standards Tuesday, requiring the U.S. auto fleet to average 54.5 miles per gallon by 2025, an uncontroversial move that, unlike other administration energy policies, was endorsed by industry and environmentalists alike.
[will] expand on existing standards requiring American-made cars and light trucks to average 34.5 mpg by 2016. They will significantly cut U.S. oil consumption and greenhouse gas emissions by the time they are fully implemented, according to EPA.