South Korean President Moon Jae In holds an emergency midnight meeting with top national-security officials at the presidential Blue House after Donald Trump's cancellation of his nuclear summit with Kim Jong Un.Reuters / Blue House

To be in South Korea in mid-May—when North Korea released American hostages and Donald Trump announced his summit in Singapore with Kim Jong Un and the leaders of China, Japan, and South Korea gathered in Tokyo to talk denuclearization and reconciliation on the Korean peninsula—was to feel as if the spring of 2018 might be one of those moments when history, after plodding along for decades, suddenly moved very fast.

And pushing it along was South Korean President Moon Jae In, who had lobbied hard for talks between Trump and Kim and whose diplomatic investment seemed to be paying off as the summit approached. Even last week, when history seemed to come to a screeching halt as Trump canceled the summit, Moon kept pushing, holding his own surprise summit with the North Korean leader on Saturday. Moon had been blindsided by Trump’s decision, but he was moving to reassert control over what he still hopes could be a historic breakthrough for peace on the Korean peninsula. Human history, one of Moon’s advisers told me recently in Seoul, “is ... governed by certain law of heavenly mandate. There is a time for peace—that is a dictate of nature. And Moon Jae In is following that heavenly mandate.”’

Whatever his mandate, Moon is scrambling to save the summit, which Trump now says might still happen, despite the “trail of broken promises” an administration official accused North Korea of leaving behind. On Sunday, in fact, American officials arrived in North Korea to proceed with summit preparations. Shortly before Trump pulled out of the summit over the North’s “open hostility” and his administration’s doubts about the North’s commitment to denuclearization, South Korea’s national-security adviser had placed the odds of the Trump-Kim meeting occurring as scheduled at 99.9 percent. Sometimes history turns on 0.1 percent probabilities.

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The story of how South Korea nearly managed to bring Donald Trump and Kim Jong Un together for an unprecedented meeting, and to help pull the American and North Korean leaders back from the precipice of war, is often told as if it begins with the Pyeongchang Winter Olympics in South Korea. But the tale actually starts much earlierand it’s still unfinished.

Moon, a child of North Korean refugees and former chief of staff to President Roh Moo Hyun, a practitioner of the liberal “Sunshine Policy” of engagement with North Korea, assumed office a year ago this month anxious to pursue rapprochement with North Korea. He was determined not to repeat the mistakes of Roh, who had been openly confrontational with the United States and held a summit with North Korean leader Kim Jong Il at the end of his five-year term, when there was little time to implement the results.

But Moon—who became president shortly after a spell of heightened tension in April, when Trump dispatched an aircraft carrier to the Korean peninsula as the U.S. and North Korea traded threats of devastating war—was initially inhibited. The Trump administration was focused on applying economic sanctions and diplomatic pressure on North Korea in response to its missile and nuclear tests. Moon, whose liberal government wasn’t a natural partner of the conservative Trump administration, enlisted in the “maximum pressure” campaign.

Some of his staff argued last year that because of Trump’s pressure and sanctions, inter-Korean detente is now stalemated. We have to just ignore Trump!” Kim Hyun Wook, a professor at the Korea National Diplomatic Academy, which is affiliated with South Korea’s Ministry of Foreign Affairs, told me. “But President Moon didn’t listen to them. [He said,] ‘No that’s not true. We have to anchor the U.S.-South Korea alliance and then [undertake] inter-Korean detente all together.’”

“Sanctions and pressures are the logical response” to North Korean military provocations that violate UN Security Council resolutions, explained Chung In Moon, a special adviser to President Moon Jae In for foreign affairs and national security, when I met with him in Seoul. But they are a means to compel North Korea to negotiate, not an end in themselves. With regard to North Korea’s development of nuclear weapons, “by the very structural nature of the issue, it is between” the United States and North Korea, Moon told me, in apparent reference to the fact that the North has been developing its nuclear arsenal—particularly nuclear-capable long-range missiles—with the stated purpose of deterring a U.S. attack. (Many South Koreans doubt that North Korea would actually use its nuclear weapons and see those weapons as primarily threatening the United States.) But the South Korean president has made clear that “as to peace, stability, and prosperity on the Korean peninsula, it is we who should sit in the driver’s seat.”

The South Korean president is essentially a “functionalist,” Moon continued, intent on initiating a lengthy process in which economic exchanges and other forms of cooperation between the Koreas function as a gateway to peaceful coexistence, then to de facto unification between sovereign nations, and perhaps then to more formal unification if it occurs naturally.

President Moon outlined all this—and a roadmap for how talks on denuclearization and inter-Korean peace could progress in tandem that closely resembles the flurry of diplomatic activity in recent months—in a July speech in Berlin, where he expressed hope that East and West Germany’s unification could be replicated in Korea, the “last divided nation on this planet.” But the address fell on deaf ears in Washington, which just days earlier had watched North Korea become a direct threat to the mainland United States for the first time with the successful test of an intercontinental ballistic missile. “We have reached the tipping point of the vicious circle of military escalation,” Moon warned in Germany. In fact, that tipping point was yet to come.

Throughout the summer and fall, North Korea tested longer-range missiles and its most powerful nuclear bomb, Trump taunted Kim Jong Un with “fire and fury,” and U.S. officials suggested they were on the verge of exercising military options to prevent the North from becoming capable of striking America with nuclear weapons. The language from Washington “really scared” the South Korean president, said Chung In Moon. President Moon’s vision fell away in the face of a more immediate concern: averting another catastrophic conflict on the Korean peninsula. President Moon declared in a not-so-veiled message to the Trump administration in August that no country could take military action against North Korea without South Korea’s consent, and that “war must never break out again on the peninsula.”

But even as North Korea vowed to conduct an atmospheric nuclear test over the Pacific Ocean and reports surfaced of serious U.S. military planning for strikes against the North, Moon was clawing his way to the driver’s seat behind the scenes.

A pivotal moment came in November, when “President Moon won [Trump’s] heart” during the American president’s trip to South Korea, Chung In Moon said. The South Korean leader made a surprise appearance at the U.S. Army garrison where Trump was having lunch with soldiers and then welcomed Trump’s request, at a state dinner that Chung In Moon also attended, to visit the border with North Korea. “President Moon said, ‘Why not?’” Chung In Moon recalled. “The next day our president went to … the Demilitarized Zone, waiting for President Trump from 5 o’clock in the morning until 9. But President Trump’s helicopter couldn’t land because of fog.” Even so, these gestures built “trust between the two leaders.”

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Moon is the type of the progressive South Korean leader that the Kim government has traditionally engaged with. A senior South Korean official, who requested anonymity due to the sensitivity of negotiations with North Korea, told me that that the Moon government “sent a consistent message to North Korea that it was open to dialogue any time, any place” and that President Moon “from the beginning wanted to take advantage of the Olympics as a window for starting dialogue.” But for a while, Chung In Moon told me, “North Korea was not responding,” despite President Moon’s often-lonely months-long campaign with the International Olympic Committee to persuade the North to attend the competition.

It wasn’t President Moon who ultimately broke the war fever. It was Kim Jong Un. First Kim declared his nuclear program “completed” in late November after testing his most sophisticated long-range missile yet. Then, in a New Year’s speech, he proposed sending a North Korean delegation to the Olympics and opening a dialogue to achieve peace on the peninsula, even as he instigated a nuclear button-measuring contest with Donald Trump. Kim’s speech “changed everything,” Chung In Moon said.

The Moon government sprang into action, offering high-level talks within days of Kim’s overture, and began working on a Trump administration that was still very much in a defensive crouch. A critical moment came just a few days after Kim’s address, Chung In Moon told me, when Trump agreed in a phone call with President Moon to “bless” South Korea’s talks with North Korea and accept Moon’s proposal to postpone U.S.-South Korea military exercises until after the Olympics. (During the call, Trump reportedly asked Moon to publicly credit him for forcing North Korea into negotiations, which Moon has since done profusely—repeatedly recommending before the summit collapsed this week that Trump receive the Nobel Peace Prize.) Prior to the call, Chung In Moon recalled, “we [were] all expecting another round of crisis on the Korean peninsula starting from January that could have jeopardized” the Olympics.

As for what motivated Trump’s about-face, it’s an “enigma,” Moon told me, “but we worked hard.” Trump “was quite realistic,” he continued. “On the one hand he was putting pressure on North Korea” with sanctions and military threats, which played a role in Kim’s calculations. “On the other hand he was encouraging President Moon to talk to North Korea.” Trump “deserves credit and recognition for his leadership,” the senior South Korean official told me, particularly for his prioritization of the North Korea issue and mobilization of international support for sanctions.

This was a period where President Moon was acting as a “catalyst” and “moving out ahead” of the other stakeholders in the standoff over North Korea’s nuclear weapons, “trying to create this aperture,” John Delury, a Korea expert at Yonsei University in Seoul, told me. “I think he correctly read that Trump doesn’t want to go to war” despite the U.S. president’s tough talk. “Moon was helping to create something Trump wanted.”

Moon successfully presented himself as a “good mediator” between Kim Jong Un and Donald Trump when high-level American and North Korean delegations visited South Korea for the Olympics in February, Chung In Moon said. President Moon was trying to turn these odd moves by President Trump and Chairman Kim Jong Un into some kind of a coherent whole for dialogue and negotiation,” he explained. “If there [had been] no Pyeongchang Olympic Games, where else would we be able to find momentum?” asked Kim Hyun Wook.

The diplomatic theatrics flowed from there: the American vice president expressing a willingness to talk with North Korea; South Korean officials jetting from Pyongyang to Washington with a message that Kim was prepared to stop nuclear and missile tests and discuss denuclearization, prompting Trump to agree on the spot to a summit with the North Korean leader (“That was a very, very shocking thing,” Kim Hyun Wook said); China and Japan leaping into the fray to avoid getting left out; a North Korean leader stepping into South Korea for the first time to commit to many of the key components of Moon’s plan for securing inter-Korean detente: joint economic projects, an official end to the Korean War, a peace treaty and the denuclearization of the Korean peninsula. Injecting itself into a crisis with no clear road ahead, South Korea charted one. And the other parties, however haltingly, began to follow.

“Nobel Prize to Trump, peace to Koreans,” Chung In Moon mused in the afterglow of the inter-Korean summit, noting President Moon’s strengths as a “good listener,” an “efficient facilitator,” and an “open-minded guy.” President Roh, who both Moon Jae In and Chung In Moon worked for, had “clear historical vision,” he said, but Roh “really cared about his name in history. Moon Jae In, he doesn’t care. He’s very pragmatic.”

* * *

This week, Moon’s high-wire diplomacy nearly unraveled as quickly as it took shape. When I spoke to Delury earlier this month, he spoke approvingly of the South Korean president “going [out] on a limb” and “putting some of his political capital down to vouch for Kim” in order to jump-start negotiations with North Korea. But others saw in these efforts a man in a hurry getting perilously far ahead of reality.

Moon “keeps acting like North Korea’s spokesperson” and conveying North Korea’s positions in “the best light,” said Han Sung Joo, a former South Korean foreign minister who helped negotiate an agreement that temporarily resolved the first North Korean nuclear crisis in the early 1990s. In fact, Han told me, Kim Jong Un may simply be interested in easing sanctions to strengthen the North Korean economy and receiving international acceptance of his nuclear weapons, not in giving up those weapons in exchange for transformed relations with South Korea and the United States.

When I asked the senior South Korean official earlier this month whether North Korea was prepared to completely denuclearize, the official responded, “That’s a big question. Skepticism is always healthy, but I am optimistic.” On Sunday,  after meeting with Kim Jong Un on the north side of the Demilitarized Zone, Moon reaffirmed Kim’s “will for the complete denuclearization of the Korean Peninsula” but cautioned that Kim’s reservations about whether the United States will really “end hostile relations [with North Korea] and guarantee the security of the [North Korean] regime” in exchange for denuclearization is currently testing that will.

Whereas Chung In Moon praised the declaration in April by the leaders of South and North Korea of “a new era of peace” and “no more war” on the Korean peninsula—as an illustration of the the “primacy of peace” over unification in the president’s vision of inter-Korean detente—former South Korean national-security adviser Chun Yung Woo considered these pledges, along with promises of economic projects, hasty. With the declaration, Kim Jong Un bought an “insurance policy for a failure in the summit with Trump,” Chun told me.

What such statements suggest is that if Trump returns to sanctions and military planning following a failed summit with Kim—or instead of any summit at all with Kim—South Korea “will not support him,” Chun said. “We stand to delegitimize Trump’s military option [against North Korea], which is not about use of force but to hold the most important leverage that the U.S. needs to achieve denuclearization. … And by promising implicitly the resumption of economic cooperation without linkage to progress and milestones on denuclearization, I think [Moon] made too much of a promise of a down payment before he even sees the things that he will buy from North Korea.” Kim, not Moon, “is in the driver’s seat,” Chun continued. The North Korean leader “chose the timing, the circumstances” of engagement, and “Moon is playing, in some ways, Kim Jong Un’s game.”

Chung In Moon, however, told me that implementation of the inter-Korean declaration depended on the “success or failure of the Trump-Kim summit.” And at the time he acknowledged success was not guaranteed. “The U.S. cannot make North Korea surrender,” he said. “We all know what we want from North Korea. But we do not know what North Korea wants [and] what Trump can give to North Korea.” These, he noted, are the “variables in the equation.”

Last week the variables did not resolve in South Korea’s favor, highlighting the limits of its control over the diplomatic process that it carefully crafted. But variables, by their nature, just might surprise us yet again. Donald Trump is now talking of resuscitating the scrapped summit in response to conciliatory gestures from North Korea. And South Korea’s president remains the constant in the diplomatic equation, speaking confidently on Sunday about future talks between the U.S. and the two Koreas even as present talks twist in the wind. “Denuclearization and the lasting peace on the Korean peninsula cannot be abandoned or delayed,” Moon said in a statement shortly after Trump ditched negotiations with Kim Jong Un. “They are the historical assignment.”

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