Coming against all odds, enduring withering criticism and facing deep cynicism, President Donald Trump announced his decision to become the first sitting American president to meet North Korea’s supreme leader. The Kim family regime has invited previous presidents to meet, but Trump’s swift acceptance of Kim Jong Un’s invitation is a bold gamble that seizes an opportunity produced by a hard-edged pressure strategy. Assuming it takes place by May, the summit is also made possible by Kim’s recent burst of diplomatic dexterity. The two leaders are mirroring one another, gambit for gambit.

The Trump administration’s much-maligned North Korea policy always included two countervailing parts, like the positive yin and negative yang forces in the circle of the South Korean flag: engagement and maximum pressure. Before the Olympics, pressure took center stage; now it appears likely that post-Olympics will focus at least for a while more on engagement and diplomacy.

The criticism of Trump will continue, not least for leaping at what will be a hastily prepared summit meeting between two leaders whose countries have been locked in a bitter struggle since the 1953 armistice. But just as critics mostly erred in reading the Trump administration’s North Korea policy before this announcement, many will again reflexively sow doubts on the decision, chiefly because of Trump’s temperament and style.

It is important to remember that there is a model for such an unscripted adversarial encounter.

Indeed, there are two basic types of bilateral summit meetings when dealing with a foe: the planned and the unplanned. A good example of the former is the 1972 meeting in Moscow where President Richard Nixon and Leonid Brezhnev signed the first agreement on Strategic Arms Limitations Talks (SALT). The entire event was carefully orchestrated. As Henry Kissinger wrote to the president a year before the summit, “If we play our cards right, we can hope for some constructive results.”

Examples of breaking-the-ice encounters devoid of earth-shattering agreements also can be found from the diplomatic archives of U.S.-Soviet diplomacy. These include Dwight Eisenhower’s bold invitation for Nikita Khrushchev to visit the presidential retreat at Camp David, as well as Ronald Reagan’s unscripted tête-à-tête with Mikhail Gorbachev in Geneva in 1985, which after ups and downs eventually led to an Intermediate Nuclear Forces treaty.

While North Korea is not the Soviet Union, planning for a Trump-Kim summit is reminiscent of the tortuous road leading to the 1959 Camp David tête-à-tête, which marked the first bilateral meeting between U.S. and Soviet leaders after the onset of the cold war. The recent war of words between the American and North Korean leaders and governments is redolent of some of the bitter exchanges of the late 1950s. Back then, as now, many commentators warned against inviting an adversarial leader to a summit meeting, especially to a presidential compound. As a prominent journalist of the day put it, especially after the Soviet Union suppressed opposition to its occupation of Hungary in 1956, and then in 1958 executed Premier Imre Nagy and his advisers: “No man with such blood on his hands can hope to be received in such quarters.”

But the unthinkable happened. Khrushchev did visit America and the president’s retreat. While the East-West competition did not end, a certain positive spirit lingered and informed the arms control talks and détente that eventually produced the downfall of the USSR. Trump’s gambit does, then, have a basis in history and deserves cautious support.

Kim’s intentions remain unknown and they are very possibly malign. Perhaps his true aims are to bust the sanctions regime without relinquishing his nuclear-armed missiles. After all, being a nuclear-weapon state is now part of North Korea’s constitution, and his New Year’s about-face on North-South relations included a pledge to mass produce missiles equipped with nuclear warheads capable of striking the United States.

But there is some reason to believe Kim acted at least tactically to nip the mounting pressure campaign in the bud. He could read the writing on the wall: Trump meant maximum pressure until concrete results were achieved, the U.S.-South Korean alliance was holding strong despite political differences, China was increasingly on board with pressure, and elites might already be feeling the pinch from a sharp curtailment of foreign currency flowing into North Korea. Maybe now was the right time to cut a deal and at least buy more time.

The 34-year-old Kim has demonstrated impressive diplomatic agility in 2018: He pivoted to South Korea in his New Year message, reversing his previous animus for Seoul; he then agreed to a North-South summit in April, when for only the third time in history the leaders of the two Koreas will meet; and now he has invited and received an acceptance for a summit with the U.S. president.

Candidate Trump once opined he would be open to a summit, perhaps over hamburgers; he now has a chance to make good on that notion and then some. Here is what is likely to happen between now and a Trump-Kim meeting in April or May.

First, joint U.S.-South Korean military exercises will take place in April, but they are likely to be scaled back. The revisions are apt to be cosmetic or modest signs of restraint, such as withholding strategic forces from playing a prominent or any role in these drills. Readiness, training and deterrence are essential, and no one has talked about North Korea altering its annual winter and spring exercises. Even so, further modifications could come in future, calibrated to the evolving security environment.

Second, President Moon Jae-in and Kim will meet in April at Panmunjom. This is the site of a daring defection and shooting incident in November but also the only place along the demilitarized zone where North and South Koreans face each other up close. Because international sanctions and other constraints properly will remain in place, Moon may only be able to talk to Kim about the possibility of selectively lifting sanctions. For instance, he may seek to reserve some South Korean unilateral sanctions, such as the May 24 sanctions put in place after the sinking of the Cheonan ship that left 46 South Korean sailors dead. They are also likely to discuss investment plans, such as reopening the Kaesong Industrial Complex, the Mt. Kumgang Tourist Area for reuniting families, and other infrastructure plans enumerated in the two previous summits between North Korean leader Kim Jong Il and Korean presidents Kim Dae-jung and Roh Moo-hyun in 2000 and 2007.

Third, preliminary discussions involving a senior Trump administration official or envoy will help pave the way to a summit. Given that Kim has not left North Korea since rising to power in December 2011, the likelihood is that Trump and Kim will also meet on the North Korea border. More important, having succeeded in securing Kim’s apparent willingness to discuss denuclearization and freeze nuclear and missile testing while talks take place, the most immediate goal is to convert the rhetoric into reality through a verification process for Kim’s nuclear weapons programs.

Momentum could falter, of course. It will be important not to abandon the policies that produced this limited initial breakthrough: pressure and engagement. Even now, the United States must resist the temptation to let up on pressure before there are concrete reciprocal steps taken by North Korea to reduce the threat.

Only months ago, the world feared ever-rising tensions and a potential nuclear war. Trump (together with Moon) and Kim have altered that narrative and in dramatic fashion. The path ahead is long and uncertain, and announcing summits is much easier than sustaining a successful process. But a Trump-Kim summit will be historic and could well create a path leading to the end of the Korean War.

Patrick Cronin | Center for a New American Security

Cronin is the senior director of the Asia-Pacific Security program at the Center for a New American Security, where he is leading a two-year project on North Korean diplomacy.