John Kerry: “It will guarantee that Iran's program is under intense scrutiny.”

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.

It's very obvious that there are huge threats here.

Coal is the dirtiest fuel in the world, and emissions that are not captured from coal are the worst cause of the warming of the ocean.

It's a matter of mathematics and physics, not politics, not ideology. It is a response to the science.