and let's be clear here. but bashar al as sad. >> there is little doubt that he is responsible. he has the resources. he has done this many times before and two, this is not just a chlorine attack but also involved some nerve agent. one handicap the united states has is they don't have boots on the ground to capture the evidence themselves. it is not about who did it and what they used. it is about how hard the evidence is that you have to