Government-mandated and -subsidized ethanol from corn will go down in history as the "Iraq War" of environmental solutions: ill-considered, costly, and disastrous.

I've had a chance to meet some of my civil rights heroes and, more recently, members of the young generation around [Barack] Obama, people in their teens and twenties who were determined to make history and who were too idealistic to think that what they were trying to do might be impossible. They proved that visionary pragmatism can win over the majority. That comes from a particular place in your heart that generation Y is offering America. They just can't afford to be naive now, in terms of the ferocity of the opposition.

Now we stand at our own crossroads, looking out upon two futures: one with rising temperatures, rising oceans, and rising violence on a hot and strip-mined planet and another with expanding organic harvests, growing solar arrays, and deepening global partnerships on a green and thriving Earth.

The problem isn't that the green jobs aren't sexy enough. It's that they're not plentiful enough. A young person looking for a job isn't looking just for a sexy job, they're looking for any job.

America should be leading the world in green and clean solutions, and human rights. We shouldn't be leading the world in wars and incarceration rates and pollution. We can be a better country. I think we're going to be a better country.

Clean coal represents a breakthrough in the marketing of coal, but not in the science of burning coal.

There are some cities that are doing good stuff, but there aren't enough of them. If you don't fight for what you want, then you deserve what you get. And in politics, if you don't ask, you don't get at all.