President Donald Trump allowed the Iran nuclear deal to survive through 2017.<br />2018 will afford him another chance to blow up the agreement.<br />Critics and supporters alike believe he may take it.<br />By mid-January, the president will face new legal deadlines to choose whether to slap U.S. sanctions back on Tehran.<br />The deal was negotiated in 2015 by the Obama administration. Killing the deal would damage Obama's legacy.<br />Trump promised he would revoke the deal. <br />
