There's a great opportunity out there for science to move toward new ways of creating energy. Obviously much more work needs to be done to make hydrogen more efficient and useful as an energy source, but the technology is growing and becoming more and more viable every week. I can see a huge industry growing out of alternative energy - one that can eventually compete with the oil companies. There's the possibility of economic growth as a result of emerging alternative energy sources, not just hurting an existing industry. I'm also not saying hydrogen is the only way to do it, but it definitely is one of the ways to start making inroads in making the United States energy independent.

And in response to this thread's topic - I would say that ethanol is not nearly a comprehensive enough solution. It is not as efficient as gasoline, making it an unlikely replacement. I would say biodiesel is much more efficient and likely of a replacement. Anyway, these are just my two cents.