Erdogan said John Bolton, who held talks with Turkish officials in Ankara on Tuesday but left without meeting the president, "made a serious mistake" in setting conditions for Turkey's military role after the U.S. pullout. The rebuke highlights the difficulties in implementing Trump's goal of bringing home some 2,000 U.S. troops stationed in Syria. Trump's plan, clouded by mixed messages from the president and his administration, hinges on Turkish cooperation to secure a huge swathe of northeast Syria as the United States departs.