One of the few remaining options was to “persuade China” to “remove the regime in North Korea” and permit the reunification of the Korean peninsula. This was characterized as a “diplomatic option.” But Bolton doubted the Chinese could be convinced to reverse their longstanding policy of resisting regime change in North Korea. The United States is thus fast approaching a “binary choice”: live with a North Korea capable of attacking America with nuclear weapons, which Bolton claimed was intolerable, or take military action to avert that outcome, which he suggested was tolerable if unpalatable.

In March, after Trump shocked the world by agreeing to discuss “denuclearization” with Kim Jong Un by May, Bolton went on Fox News to applaud the meeting—not because it could resolve the nuclear crisis peacefully, but because it could quickly expose Kim Jong Un as a con man. When Kim balks at Trump’s demands to immediately give up his whole nuclear-weapons program and ship it off to the U.S., Bolton reasoned, the North Korean leader’s true motivation will be revealed: buying time through protracted negotiations to perfect nuclear-tipped long-range missiles that can reach the United States.

Bolton set a towering bar for success at the summit: not just complete and instant denuclearization, which most experts consider unachievable, but also voluntary regime change: “If Kim Jong Un comes in and says, ‘You know, I’ve seen the error of my ways. I’m gonna renounce my leadership of North Korea and go live in a villa on the seashore of China for the rest of my life and the regime can get on without me,’ that would be historic, but unlikely,” he said. Bolton went on to tell a kind of joke: “Question: How do you know that the North Korean regime is lying? Answer: Their lips are moving.”

If sanctions and diplomacy won’t stop North Korea from developing a long-range nuclear capability, and if a nuclear-armed North Korea is unacceptable, then that leaves no carrots and only the biggest of sticks: military force. In recent weeks Bolton has noted that North Korea is thought to be only months away from being able to deliver nuclear warheads to the United States, and that the U.S. might not be able to deter the reckless Kim regime from either using those weapons against America or selling nuclear and missile technology to American enemies like Iran or even terrorist groups. As a result, he’s argued, “striking first” to eliminate the “imminent threat” from North Korea qualifies as “self-defense” and “is perfectly legitimate.”

Bolton, who previously proposed U.S. military action to prevent Iraq and Iran from wielding weapons of mass destruction, has described in detail what preventive strikes against North Korea could look like. In August he wrote that the United States could try to destroy any North Korea missile poised for launch at America; target North Korean nuclear and missile facilities, launch sites, and submarine bases with cyberattacks or bombing raids from the air and sea; or take out North Korea’s leadership with airstrikes or special-operations forces and then dispatch ground forces to seize North Korea’s capital, nuclear program, and military sites.