In the days following the 2020 presidential election, fears ran rampant that Donald Trump, having lost the election, would try to do something truly crazy like launch a missle strike or deploy troops to prevent an orderly transition. But among the grownups at the Pentagon, there was one even bigger fear:

For the Joint Chiefs, the biggest worry was the revival of one of Trump’s hobbyhorses: pulling troops out of Afghanistan, what he had called the “loser” war. A long line of advisers—Mattis, McMaster, Kelly, Mike Pompeo, and former secretary of state Rex Tillerson among them—had repeatedly discouraged this idea from the first time Trump brought it up in 2017. American intelligence units in the region needed military support to keep up their work. The United States had hundreds of millions of dollars’ worth of equipment and vehicles on the ground that would have to be methodically removed, or else they could be confiscated by the Taliban and make enemy forces that much better equipped to terrorize civilians and attack the Afghan government. Even if Trump decided to dramatically reduce forces in the region, his generals and top advisers warned him that pulling out of Afghanistan wasn’t as simple as putting a bunch of soldiers on a bus and heading out. Withdrawal had to be executed carefully and in stages, protecting each flank and helping the Afghan government remain stable.

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Pentagon leaders worried about a Saigon situation, with a chaotic last-minute exit and desperate people rushing to a rooftop to catch the last helicopter out. The Joint Chiefs began preparing for the possibility. If the president ordered a military action they considered a disaster in the making, Milley would insist on speaking to the president before passing on the order, so he could advise against it. Under this plan, if the president rejected Milley’s counsel, the chairman would resign to signal his objections. Then, with Milley out of the picture, the Joint Chiefs could demand in turn to give the president their military advice. This would buy time. In informal conversations, they discussed what would happen if they, too, got the brush-off from Trump. They considered falling on their swords, one by one, like a set of dominos. They concluded they might rather serially resign than execute the order. It was a kind of Saturday Night Massacre in reverse, an informal blockade they would keep in their back pockets if it ever came to that.

— Carol Leonnig and Philip Rucker
I Alone Can Fix It: Donald J. Trump’s Catastrophic Final Year