From the campaign trail to the White House, President Trump has long bashed the Iran nuclear deal. “One of the worst deals I’ve ever seen.” But in May 2017, September 2017 and again today, he has opted to waive certain sanctions on Iran. The question is: Why? Theory 1: He’s buying time. Trump wants to figure out how to address what he calls Iran’s destabilizing activities, like its involvement in Syria and its ballistic weapons program. Both are outside the scope of the nuclear deal. Theory 2: The recent protests in Iran about the bad economy altered his thinking. Trump’s advisers think that the protests give the president leverage to continue creating uncertainty about America’s commitment to the deal, rather than killing it altogether. Theory 3: He’s actually killing it behind the scenes. Iran watchers are calling the strategy, “death by 1,000 paper cuts,” where the U.S. is creating uncertainty about the future of the nuclear deal, hoping that Iran backs out first. Theory 4: His advisers are O.K. with the deal, but his base isn’t. Defense Secretary Jim Mattis openly split with Trump on abandoning the deal. But it has long been one of Trump’s red meat appeals to his base.