What remained a mystery throughout McMaster’s tenure, however, were the underlying motivations for his hardline posture. Did McMaster, a former tank commander and Vietnam War scholar who was intimately acquainted with the tragic unpredictability of war, truly believe it preferable to engage in a catastrophic conflict with North Korea than to live with a nuclear North Korea? Did he have some reason to believe that U.S. officials had gotten North Korea wrong for decades and that the Kim regime, faced with American military might, would fold rather than fight back? Or did he merely think that the only way to compel China to crack down on North Korea, and North Korea in turn to give up its nuclear weapons, was for U.S. military options to appear credible even if they were ultimately a bluff? Before becoming national-security adviser, McMaster often argued that there were times when the United States couldn’t “RSVP ‘no’” to conflict—when, to paraphrase the famous aphorism, war was interested in Americans even if Americans weren’t interested in war. But he also liked to quote George Washington’s advice that preparing for war was one of the best ways to prevent it.

As John Nagl, who worked on counterinsurgency with McMaster during the Iraq War, told me in regard to McMaster’s talk of war with North Korea: “I find it absolutely inexplicable—not in keeping with the man I know, with his writing, with his thinking, with the sense of responsibility he feels for preserving peace and security and innocent life.”

When John Bolton talks of war, on the other hand, it’s more explicable. “Question: How do you know that the North Korean regime is lying? Answer: Their lips are moving,” he said on Fox News shortly after news broke that Trump and Kim Jong Un had agreed to participate in direct talks on “denuclearization” by May. The North Koreans aren’t going to voluntarily abandon their goal of obtaining nuclear-tipped long-range missiles, he argued. “They want to buy time: three months, six months, 12 months—whatever it is they need to get across the finish line. What Trump did … is foreshorten that period” by organizing a meeting that can quickly expose North Korea insincerity about relinquishing its nuclear program anytime soon. (“I may leave fast or we may sit down and make the greatest deal for the world,” Trump himself recently predicted.) “Rather than having the low-level negotiations rising to the mid-level negotiations rising to the high-level negotiations, finally rising to a summit meeting—that’ll be two years from now, they’ll have deliverable nuclear weapons,” Bolton explained. “That we cannot allow.”

Ahead of the first summit in history between the leaders of the United States and North Korea, the Trump administration’s North Korea policy has now lost its head (McMaster) and its heart (Secretary of State Tillerson and the State Department’s top North Korea diplomat Joe Yun). With the selection of Mike Pompeo as secretary of state and now Bolton as national-security adviser, the body of the policy is regenerating, more aggressive than ever. But what’s left at the moment are the president’s gut instincts. Donald Trump and Kim Jong Un are due to meet in a couple months.

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