Chuck Hagel: “The world needs to establish a new global consensus on nuclear disarmament and nonproliferation.”

The Chinese are watching this as relates to Taiwan, the Iranians, the North Koreans -- all countries are watching this, and watching the U.S. response to it, and the West response to it.

Climate change is a national security threat.

This is so unpredictable. And we've never seen anything quite like this in our lifetime, so there is no playbook here.

It just feeds into all that instability, and unrest, and unpredictability, which makes a damn dangerous world.