will he strike? >> the president, of course, has the authority to act. it's neither his desire nor his intention to use that authority absent congress backing him. >> has the authority to act. john, what does this tell us? what's going on behind the scenes? >> what it tells us is the white house is ready to act if they need to, but they can't say publicly that they'll act without a congressional vote because that will take the momentum that's already moving against them in congress and compound it even further. this is a delicate line the president needs to walk. that's why that tuesday speech is so important. this is about the power of the bully pulpit. the responsibility of the president to go to a war weary nation and a deeply divided congress and to make the case that this is about principle. >> we were listening to the president speaking from russia. he said -- i believe he said he feels pretty confident once these members of congress go in these classified briefings that they will know that it is assad who committed these atrocities. yet -- let me play that sound. let me compare it to what one congresswoman out of california had to say. roll it.