As far as I know, the line of communication between the U.S. and Russia continues to be open and the battlefield commanders are able to communicate with one another. I am aware that there have been certain public statements made out of Moscow.

We are making tremendous progress that ISIS really does present to the homeland and to other homelands of allies around the world.

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 the Russians have played now for some time the role of providing cover for Bashar al-Assad's behavior. The alternative explanation that the Russians put forth is simply not plausible.

I do not think Syria can achieve international recognition in the future - even if they work through a successful political process, you know, the international community simply is not going to accept a Syria led by the Assad regime.

My understanding, I was not standing nearby, but my understanding is that President Xi Jinping said, "Well, no one should kill children." The Chinese have since issued their own statement on the Syria attack itself.

Russia and the USA are two largest nuclear powers in the world; it's a really important relationship. How do we start making this work? How do we live with one another? How do we work with one another? We simply have to find a way to go forward.