CalCars has displayed this 100+ miles per gallon Plug In Hybrid adaptations for the last few years: this picture was from April 2007: people are driving these around. Detroit can build Plug In Hybrids (PHEVs) and electric cars (EVs) now.
So they can make them.
But they won't....yet.
Well, first, we must use up all the oil.
They don't want to do it right yet...
So: whats a way to get these off the drawing board? Now?
Place deposits on them. Put together a large enough group - including the million or so fleet buyers who need efficient fleets:
You have a $50 Billion Plan to Jumpstart Detroit
Taxpayers have already paid for (via Section 136 innovation funding in the 2007 Energy bill) almost $800 million to G.M. to develop the Chevy Volt electric car.
Ford also developed a Plug In version of the Ford Escape Hybrid, that's been driving for a year tested by Southern California Edison - and gets well over 100 miles per gallon. All Plug In Hybrids can do that. People pay to get Prius's converted to Plug ins.