This week Defense Secretary Jim Mattis, thought to be one of the sane and sober voices remaining in the regime, resigned in a public letter rebuking Trump’s treatment of allies and deference to authoritarians. Trump’s abrupt withdrawal of U.S. troops from Syria was the last straw for Mattis, a decision reportedly made on a call with Turkish President Recep Tayyip Erdogan the week before. Mattis’ departure elicited bipartisan concern, and placed the country on edge.