not enthusiastic about acceptediacceptesending the president's daughter. with tensions looming over north korea, the stakes were higher than a typical closing ceremony. we learned that one is leaving his post. let's get the latest from ivan watson. >> reporter: the point man in the state department dealing with north korea. he is a veteran diplomat with 30 years in the foreign service. he insists he is retiring and it is due to his own decision. the state department says secretary of state rex tillerson accepted his resignation with regret. former diplomats and colleagues of mr. yun are saying this is a big blow to the state department. that he is the best of the best. extremely experienced man who