There's such a wide variation in tax systems around the world, it's difficult to imagine a harmonized CO2 tax that every country agrees to. That's not in the cards in the near term. But the countries that are doing the best job, like Sweden, are already doing both of these. I think that eventually we'll use both of them but we need to get started right away and the cap-and-trade is a proven and effective tool.

The gay rights movement of recent years has been an inspiring victory for humanity and it is in the tradition of the civil rights movement when I was a young boy in the South, the women's suffrage movement when my mother was a young woman in Tennessee, the abolition movement much farther back, and the anti-apartheid movement when I was in the House of Representatives. All of these movements have one thing in common: the opposition to progress was rooted in an outdated understanding of morality.

I strongly believe in the separation of church and state. But freedom of religion does not mean freedom from religion, there is a better way.

A day will come when our children and grandchildren will look back and they'll ask one of two questions. Either they will ask: "what in God's name were they doing?" or they may look back and say: "how did they find the uncommon moral courage to rise above politics and redeem the promise of American democracy?"

It is my deep personal conviction that abortion is wrong. I hope that some day we will see the current outrageously large number of abortions drop sharply...let me assure you that I share youR belief that innocent human life must be protected.

The cumulative amount of man-made global pollution that's in the atmosphere now traps as much extra heat energy every day as would be released by 400,000 Hiroshima-class atomic bombs exploding every day. It's a big planet, but that's an awful lot of energy.

Global warming, along with the cutting and burning of forests and other critical habitats, is causing the loss of living species at a level comparable to the extinction event that wiped out the dinosaurs 65 million years ago. That event was believed to have been caused by a giant asteroid. This time it is not an asteroid colliding with the Earth and wreaking havoc: it is us.