In a recent piece for The Atlantic, James Jeffrey defended McMaster’s logic for preventive war. Jeffrey argued that the national security adviser may possess a superior understanding of Kim’s aims. These aims, Jeffrey wrote, include the acquisition of a nuclear-tipped ICBM; the undermining of America’s security guarantees to its allies in the region; and, ultimately, the invasion and reclamation of the South. While using force against North Korea would be destructive, it may also be the “least bad” alternative to Kim’s eventual attempt at conquest, according to Jeffrey.

While no American strategist or policymaker can say with conviction that he fully grasps North Korea’s objectives, both McMaster’s logic and Jeffrey’s defense of it are riddled with holes. History and strategy indicate that McMaster’s least bad option would be an invitation to disaster.

McMaster, a voracious student, knows that the history on the Korean Peninsula since 1953 undermines his case. Since the end of the Korean War, which concluded with an armistice instead of a full peace treaty and left a large U.S. military presence in South Korea, North Korea hasn’t behaved as a benign actor. It has long held Seoul hostage with a massive conventional arsenal positioned along the demilitarized zone. It has engaged in periodic acts of aggression, like its sinking of a South Korean warship and the shelling of a small island in 2010. It also makes extravagant, pugnacious threats to its neighbors. Yet, through all that, American conventional and nuclear deterrence has largely held North Korea at bay.

Pyongyang’s retaliation against a conventional invasion by the United States would be devastating. This reality, as Jeffrey noted, has dissuaded Washington from taking that drastic step. North Korea, then, has already proven it can deter the United States. But that doesn’t necessarily negate its desire for a nuclear arsenal for defensive purposes. Indeed, North Korean interlocutors have often pointed to the U.S. invasions of Iraq and Libya to make the case that their only guarantee of security may be nuclear weapons—the ultimate deterrent.

Now that Kim has acquired nuclear weapons, a first strike by America against his regime should be a total non-starter. Yet the Trump administration has reportedly considered a “bloody nose” strike on North Korea’s military facilities to coerce Pyongyang, in hopes of punishing the regime with attacks on discrete defense facilities or platforms while blunting its military response. But it makes little sense for American war planners to assume a “limited” strike like this would stay limited. A U.S. operation may not achieve its objectives, and even if it does, it would still leave the decision of whether or not to retaliate up to Kim. The North Korean leader would make that decision based on his own beliefs about the strike once it took place, not based on American wishes for his response. If he did decide to hit back, the result could be the most calamitous U.S. conflict since World War II.