Perhaps the most ominous revelation of the recent contretemps over Kim Jong-un’s health was that Washington has contingency plans in the event of North Korea’s collapse. That means military action, potentially in the midst of chaos, civil war, and Chinese intervention.

After being out of public view for three weeks, Kim suddenly reappeared. Why he stayed secluded is unknown, though some analysts speculated that he was practicing a North Korean variant of social distancing to avoid COVID-19—even though his government denies the presence of any cases.

However, the mystery about his whereabouts sparked a cottage industry predicting what might happen if he was permanently out of commission. Forecasts ran from a smooth transition to chaos and civil war.

Of course, his reemergence doesn’t eliminate the possibility of a North Korean collapse. For instance, though the Democratic People’s Republic of Korea remains quite poor, the nomenklatura, or elite, have improved their living standard in recent years. In 2018, Kim announced plans to focus on economic development. His diplomatic opening to the Trump administration was intended to achieve sanctions relief and improve people’s lives.

However, the failure of the Hanoi summit, and the president’s unrealistic expectation that Kim would surrender all his nukes, appear to have ended the U.S.-DPRK entente. In his most recent New Year’s address, Kim warned his people of hardship to come, suggesting a return to something akin to the “military first” policy of his father.

Making things even more difficult is the COVID-19 pandemic. In response, Pyongyang essentially sealed off the country, banning foreigners, ending official smuggling, cracking down on independent operators, and quarantining incoming goods. The result has been the equivalent of a radical increase in sanctions enforcement, which is putting the economic and political systems under much greater pressure.

Admittedly, the regime proved resilient during previous leadership transitions as well as economic crises. In the late 1990s, at least a half million North Koreans, and perhaps many more, died in a horrific famine. Yet the Kim dynasty survived. There was no evident threat to the rule of Kim Jong-il, Kim Jong-un’s father. The DPRK emerged as ready as ever to challenge its neighbors and America with missile and nuclear programs.

Since then, however, expectations have risen, so even other regime leaders may prove less docile as the economy craters. Ironically, Kim Jong-un’s brutal effectiveness in consolidating power—he has had at least 340 officials executed—might encourage someone to strike out lest they become a future victim.

Still, a genuine health crisis resulting in Kim’s incapacitation or death remains more likely. Although Kim is young, he has a family history of cardiovascular illness. And his health appears poor. There is also the possibility of assassination. There are unconfirmed reports of attempts on his father’s and his life. Other senior officials have died in strangely convenient auto accidents.

Whatever the cause, an unexpected death would trigger an unplanned transition. In a report for the Council on Foreign Relations, Paul B. Stares and Joel S. Wit observed that if the succession process failed and left “a vacuum at the top or a weak transitional arrangement,” an attempt by individuals or factions to seize power might result “in a potentially disruptive and even violent leadership struggle. What outcome might ensue and what course North Korea might take as a consequence is impossible to predict, but a prolonged and potentially violent contest for supremacy in Pyongyang—North Korea’s capital—would undoubtedly place immense stress on the rest of the country given how much the state is controlled from the center.”

However strong the DPRK might look, even totalitarian systems can prove brittle. Witness Romania in December 1989. If the outcome is not preordained, a serious power struggle is likely to result: there is no prize for second place in the DPRK. If an opening occurs, even a designated successor couldn’t count on anything. For reasons of either caution or paranoia, or perhaps both, Kim systematically removed most of the “mentors” chosen by his father—influential, long-time officials, like Kim’s Uncle Jang Song-thaek, who likely had ambitions of their own. With only three rulers in 72 years of independence, many influential North Koreans probably believe it is time to elevate someone other than a Kim.

The security forces, and especially the military, might use the opportunity to intervene. The armed services could fracture among competing commanders and units. To protect themselves, the Kims have separated the military services, maintained strict party oversight of officers, and rotated security officials. These actions make more likely a split and multiple armed factions if the system comes apart.

Worst would be conflict, combat, and chaos. In 2013, Bruce W. Bennett wrote a detailed report for the Rand Corporation entitled “Preparing for the Possibility of a North Korean Collapse.” He termed the DPRK “a failing state” and asserted: “There is a reasonable probability that North Korean totalitarianism will end in the foreseeable future, with the very strong likelihood that this end will be accompanied by considerable violence and upheaval.” In his view “a government collapse would develop into a humanitarian disaster, one that would likely force ROK, U.S., and Chinese intervention to resolve the resulting threats both within the region and beyond.”

Although advance thinking would obviously be useful, plans can age badly. Apparently, the U.S. and South Korea forged Operational Plan 5029 governing a possible North Korean collapse more than two decades ago, which subsequently faced sharp criticism in Seoul. Rather like World War I mobilization schedules, the existence of proposals for intervening in the North as it slides into crisis might encourage their use. Welcome though the disappearance of the Kim dynasty might seem, the process could prove exceedingly dangerous.

One possibility is a failed but nonviolent succession, in which the regime totters but seems likely to survive. Washington might hope to influence the outcome. However, America’s interest is modest at best. The Korean Peninsula matters mostly because the U.S. is defending the ROK from the North. The Cold War is over. South Korea is capable of protecting itself. A collapsing DPRK would be a good moment to leave Korea to the Koreas.

Moreover, Washington meddling could backfire: no serious nationalist in the North would want to go with America’s choice. Both South Korea and China, given their proximity, relationship, culture, language, and knowledge, would be better positioned to influence the outcome. It would likely be better for the U.S. to stay out and have Seoul’s back.

A second possibility is a power struggle that grows in intensity and begins to slide into violence. Intervention might serve several objectives: impose a friendly successor, prevent collapse into full-scale civil war, ensure that any violence is contained within the North’s borders, sweep up nuclear, biological, and chemical weapons before they are lost or used, and promote reunification. All of these are of greater interest to the Republic of Korea, which has a large army and reserve. Better to leave intervention to the South, while offering specialized assistance in collecting WMDs.

There are two additional reasons to stay out. The DPRK military is likely to resist. North Koreans have been taught for decades about the “American imperialists and South Korean puppets,” as was explained on one of my visits to Pyongyang. Indeed, outside intervention might unify contending factions in Pyongyang, since an allied takeover would displace everyone. Such a conflict would be the very war that Washington sought to prevent for nearly seven decades.

Beijing also might intervene, and it would have an easier time—a more open border without extensive military fortifications. The prime nuclear sites are close to China. The PRC has reason to fear refugees and conflict, especially involving nukes. It also would prefer to keep a buffer state, rather than risk reunification that yields an American ally hosting U.S. troops on its border. A mix of Chinese, North Korean, and South Korean forces would be volatile enough without Americans, especially given the present state of Washington-Beijing relations.

The third scenario is an ongoing civil war in which conflict has erupted, fighting threatens to pass the North’s borders, and WMDs are or might be used. A genuine crisis, but one that still most affects the surrounding states. The U.S. might offer humanitarian assistance as well as logistical support for any actions taken by South Korea and Japan to contain the damage. Washington also should accommodate Chinese involvement, which would be inevitable and even understandable. But there would be no reason for American forces to join the fight.

Some analysts assume that Washington would have to be involved, even leading such a venture. The Brookings Institution’s Michael O’Hanlon questioned “the notion that the United States could somehow outsource most of this DPRK stabilization mission to its South Korean ally” because of “the possible degree of uncertainty, confusion, and violence that could accompany many collapse scenarios.”

However, the mission would not be America’s to “outsource.” It would be South Korea’s to undertake. And Washington is no better at dealing with “uncertainty, confusion, and violence” than other nations: consider how badly it has botched a succession of Mideast crises and conflicts.

The South should begin preparing now. The U.S. should propose discussions with Seoul and Beijing over future contingencies, warning South Korea that the latter will have the lead dealing with the North. It is time for North Korea to become the ROK’s problem.

Once again the DPRK has well-earned its sobriquet of “the Hermit Kingdom.” However, there’s no reason that Kim’s health should worry Americans. The justification for Washington overseeing the Korean peninsula disappeared long ago. Let the ROK prepare for whatever might happen to North Korea. Then Washington would have one less crisis to be concerned about.