I think the President Donald Trump was quite clear in his statement that he made to the American people that Syria's continued violations of U.N. resolutions and previous agreements that Syria had entered into regarding the Chemical Weapons Accord would no longer be tolerated. I think we have stood by and watched multiple weapon - chemical weapons attacks by the Syrian regime under the leadership of Bashar al-Assad.

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.

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.

I don't believe anyone doubts the American people's values or the commitment of the American government or the government's agencies to advancing those values and defending those values.

We've seen what violent regime change looks like in Libya and the kind of chaos that can be unleashed. And, indeed, the kind of misery that it enacts on its own people.

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 would want to be fully informed before advising the president.