John Kerry: “I don't know how you lead from behind. If you are leading, you are leading.”

We're spending billions--literally, actually, trillions.

the U.N. Finance Analysis suggests that it will cost trillions of dollars. Maybe $2.5 to $4.5 trillion a year between now and 2050.

I have to admit to you, if anybody thinks it is radical to care about the protection of this planet for future generations, sign me up.

There is no current proposal or plan that has been agreed to which would require us to do that.