Weight does not necessarily equate to strength. Titanium is lighter and stronger than steel — it is also more expensive. Carbon fiber is lighter and stronger than aluminium — it is also more difficult to work. The current internal combustion petrol engines are not the most efficient way to convert fuel into motion — they are heavy and wasteful.
A better, lighter, stronger, safer, faster car is out there somewhere, and it will be cheap enough to render our existing automobile stock obsolete in a matter of a couple years after it is introduced.
But it isn’t going to be invented by Gummint fiat: just because Obama stamps his foot. And it isn’t going to happen from a Gummint-run GM or Chrysler who remain captives of the auto trade unions.
It will happen as a result of innovation. That happens best in the Free Market: something Obama wouldn’t understand if it jumped up and bit him on his arse.
Correct, but it does determine how abruptly the car will come to a stop in a collision. More weight means the car can use up some of its kinetic energy in shoving the other car. Coming to a stop in 15 feet instead of 5 feet can easily be the difference between life and death. Lightweight cars can subject the body to lethal G forces.