President Bush's proposal to focus our resources on sending humans to Mars is intriguing, but it is not the most compelling reason that Americans ought to focus our interest on the Red Planet.

We allow it to be dumped into this community asset, which is our one and only atmosphere. So that has to change, and there's really only one entity that can do that. So we have proposed a cap-and-trade system to stop that unlimited pollution, to use the forces of the market to efficiently allocate scarce permits to allow CO2 into the atmosphere. That's just one of 500 things we need to do, but it's probably the granddaddy of them all.

The need to help spread democracy and the ability to do that will be much greater if we break this addiction to oil, which gives the oil princes and sultans the power in the Mideast.

With millions of family wage manufacturing jobs lost since 2001, we need an energy bill that takes bold action to tap into American ingenuity in order to lead the world in new clean energy technology, rather than playing catch-up to the Japanese, Danish, and Germans.

Not wasting energy. It is the least sexy, but the single most important and always the least expensive. You would be very interested in a report by the McKinsey consulting firm that concluded that 40 percent of everything that we have to do to mitigate our emissions are net economic winners. They are cost effective and the most cost effective is not wasting energy. That's actually going to be the largest part of this whole journey, I believe - using less energy with the same beneficial results.

We've introduced the New Apollo Energy Act, which is, I think, safe to say the most comprehensive and aggressive bill that has been introduced in Congress because it does have the scale, scope, and ambition of the original Apollo Project, and it attacks the problem in every way you can imagine. There's no silver bullet here, but there are lots of opportunities.

All of the economic signals in the marketplace are essentially subsidizing the use of dirty fossil fuels and penalizing clean energy. There's really only one entity in society that can solve that problem, and that is government. And the air is a scarce resource.