Final transcription highlights from tonight's briefing:
Q: Does strike change Assad's military capability or send a message?
Tillerson: "This was clearly a very decisive action taken on the part of President Trump, who I think you heard yesterday said this particular heinous attack changed his view of how horrible use of these weapons are."
McMaster: "Obviously the regime will maintain a certain capacity to commit mass murder with chemical weapons we think beyond this particular air field. But it was aimed at this particular airfield for a reason because we could trace this murderous act back to that facility and this was not a small strike…what it does communicate is a big shift, a big shift in Assad's calculus. It should be anyway because this is the first time that the United States has taken direct military action against that regime or the regime of his father. So I think it was critical is with the president's decision in response to this mass murder attack but also in the context of all the previous attacks that have occurred – I think is over 50 – chemical attacks previously, post 2013 when the UN resolution went into effect. So I think it was both. It was aimed at the capacity to commit mass murder with chemical weapons but it was not of a scope or a scale that it would go after all such related facilities."
Q: Other allies take part?
Tillerson: "This was entirely a US operation."
Q: Did an emotional reaction from Trump play into this decision?
Tillerson: "I do not view it as emotional reaction at all….As President Trump evaluated this first attack, these attacks that occurred on his watch and reflected upon the prior responses or lack of responses he came to the conclusion that we could not yet again turn away and turn a blind eye to what's happened. The use of these weapons as I indicated earlier, one of the concerns we have is the more we have the more we fail to respond to the use of these weapons, the more we begin to normalize their use. And when we begin to normalize their use we are opening up wider spread use by others who would use such weapons. And I don't think we should in any way diminish the risk of the situation in Syria where there is a lot of chaos on the ground, there are elements on the ground in Syria, elements that are plotting to reach our shore and these type of weapons falling into their hands and being brought to our shore is a direct threat on the American people."
Tillerson said Russian approval was not sought but protocol was followed, including command contacts
"Our target in this attack was not Russia. It was not the Russians. It was not their forces nor any Russian individuals. Our target was this air field and the Syrian regime."