It's important to understand the policy of the U.S. towards North Korea is to deny North Korea possession of a nuclear weapon and the ability to deliver that weapon. Our strategy has been to undertake this peaceful pressure campaign we call it enabled by the four no's.The four no's being that we do not seek regime change, a regime collapse, an accelerated reunification of the peninsula, and we do not seek a reason to send our forces north of the demilitarized zone.

Obviously, the United States' own founding principles are self-determination. And I think what the United States and our allies want to do is to enable the Syrian people to make that determination. You know, we've seen what violent regime change looks like in Libya and - and the kind of chaos that can be unleashed.

Our priority in Syria, really hasn't changed. I think the President Donald Trump has been quite clear. First and foremost, we must defeat ISIS.

It's important that we keep our priorities straight. And we believe that the first priority is the defeat of ISIS. That by defeating ISIS and removing their caliphate from their control, we've now eliminated at least or minimized a particular threat not just to the United States, but to the whole stability in the region.

I think continued actions by Bashar al-Assad clearly call into any question of him expecting to have any legitimacy to continue as the leader of Syria. With each of those actions, like attack with conventional weapons, barrel bombs and block humanitarian aid he really undermines his own legitimacy.

We're hopeful that Russia will choose to play a constructive role in supporting ceasefires through their own Astana talks, but also, ultimately, through Geneva. And if we can achieve ceasefires in zones of stabilization in Syria, then I believe we will have the conditions to begin a useful political process.

I think there's a shared view and no disagreement as to how dangerous the situation in North Korea has become. I think even China is beginning to recognize that this presents a threat to China's interests as well.