what is iran hoping to achieve here? >> i think what the iranians are doing is this series of very carefully calibrated steps to slowly walk away from the conditions of the nuclear deal with president trumpkerry negotiated. their argument is if president trump abandoned the deal a year ago and europeans have not if you will filled their promises to make up for the losses, why should iran stay in the deal. but they are not leaving at won't. they are taking a series of small reversible steps. and the one that president rouhani described today is the one that would be of most concern. because it would begin to raise the level of enrichment away from reactor grade and gradually toward bomb grade. they would be a long way, more than a year away, from having enough to make even a single nuclear weapon. but it still shows you that they