evidence: Whatever their personal differences, Mattis and Milley both knew that there was a tragic inevitability to the moment. Throughout his Presidency, Trump had sought to redefine the role of the military in American public life. In his 2016 campaign, he had spoken out in support of the use of torture and other practices that the military considered war crimes. Just before the 2018 midterms, he ordered thousands of troops to the southern border to combat a fake "invasion" by a caravan of migrants. In 2019, in a move that undermined military justice and the chain of command, he gave clemency to a Navy SEAL found guilty of posing with the dead body of a captive in Iraq. Many considered Trump’s 2018 decision to use the military in his preëlection border stunt to be "the predicate—or the harbinger—of 2020," in the words of Peter Feaver, a Duke University expert on civil-military relations, who taught the subject to generals at command school. When Milley, who had been among Feaver’s students, called for advice after Lafayette Square, Feaver agreed that Milley should apologize but encouraged him not to resign. "It would have been a mistake," Feaver said. "We have no tradition of resignation in protest amongst the military."