convince senate democrats in particular to prevent anything from going forward, any bill from going forward like the one senator mcconnell tried to put on the floor this week from passing. because if that passes that would significantly tie the hands of the president to cut the deal that he's trying to cut. one of the critical things it would do that would make it very difficult is decree strict the president's ability to temporarily ease sanctions. and that's critical to any deal passing. so, what the president needs to do -- i think what he did do a little bit this week is get senate democrats to back off a little bit to say we're not going to move full throttle right away. it's going to be a very tough sell. center of gravity which is pretty unanimous against this sort of thing but many democrats as well aren't very favorable to this. what president obama has to do is cut this deal sell it strongly to his party. he's going to go to them and say look, this is the best we're going to get. it's either this or you can go home to your constituents and sell this idea of another war in the middle east.