If you start getting instability in large powers with nuclear weapons, that's not a good day.

I see climate change as one of the driving forces in the 21st century. With modern technology and globalization, we are much more connected than ever before. The world's warehouses are now container ships.

You get a series of super-typhoons into Shanghai and millions of people die. Does the population there lose faith in Chinese government? Does China start to fissure? I'd prefer to deal with a rising, dominant China any day.

Unfortunately, there's a lot of people in high places who understand the science but don't like where the policy leads them: too much government control.

Politicians have responsibility to act if the public opinion changes. Flooding, storms, droughts are all getting people talking about climate change. I wonder if someday Atlanta will run out of water?

When we talk about climate, we need to do everything we can to set the stage before the actors come on. And they may only have one chance at success. We should keep thinking: How do we maximize that chance of success?

Politicians have responsibility to act if the public opinion changes.