Eighteen short months ago, the most memorable phrase associated with the relationship between the United States and North Korea was “fire and fury.”

Today, it’s “love.”

President Trump and Kim Jong Un, the North Korean leader, are scheduled to hold a second summit meeting this week in Hanoi, Vietnam. After the two met last summer, Trump said that they “fell in love.”

“No, really,” Trump continued. “He wrote me beautiful letters.”

But will that lead to a beautiful deal? In the last year and a half, U.S.-North Korean relations have evolved rapidly through a few distinct stages, each with its unique incentives and strategies. The incentives have shifted from deterring nuclear war, to making a deal, to, perhaps, making peace.

In the summer and fall of 2017, Trump was threatening North Korea with that “fire and fury” while North Korea was miniaturizing warheads so that they could fit onto ballistic missiles and threatening to annihilate a U.S. territory in the Pacific. It was a blustery standoff for a reason. Nuclear game theory suggests that for two speeding motorists playing a game of chicken, it pays to look tough.

By June 2018, when the two leaders met in Singapore, the tactics had changed. The relationship evolved into a classic bargaining game, in which unpredictability and swagger are best swapped out for reliability and prudence. The leaders left the Singapore meeting having signed a joint statement agreeing in principle to “peace and prosperity” — though it was short, anodyne and without schedules or specifics.

And this week, in February 2019, they will meet again, playing a newer game still — and perhaps as members of the same team. “That the majority of policymakers and pundits are skeptical of the Trump process for dealing with North Korea is not surprising,” David Kang, the director of the University of Southern California’s Korean Studies Institute, told me. “But this is missing the point. For the first time in a generation, there are new leaders in North Korea, South Korea and the United States who are willing to question, and perhaps change, the status quo.”

Indeed, earlier this week, South Korean officials suggested that Trump and Kim could declare an end to the Korean War — which has been technically ongoing for nearly 70 years. The declaration could be seen as a sign of trust between the North and the U.S., as well as a step toward the elusive “denuclearization” of the North.

Trump’s and Kim’s incentives also appear aligned because of their apparent desires for a literal gold medal and some brief recognition from the King of Norway. In May, Trump was asked whether he deserved the Nobel Peace Prize. “Everyone thinks so,” he said.

It’s a notion that Trump seems to have liked.

Earlier this month, he said that Japan’s prime minister had nominated him for the award, a claim on which the prime minister wouldn’t comment. A Japanese newspaper reported that Japan had nominated Trump only after the White House asked it to. Trump was actually (or also) nominated by two Norwegian lawmakers.

Interest in the prize is also reportedly growing in North Korea, where authorities have staged a series of lectures raising the possibility that Kim could win the Nobel.

The New York Times columnist Nicholas Kristof argued recently that it is “of course, delusion to think that either Trump or Kim will win the Nobel Peace Prize.” But two solipsistic world leaders’ delusions may be the rest of the world’s saving grace.

The rapid evolution of the relationship and the pursuit of Nobel Prizes notwithstanding, full denuclearization would be slow and difficult to verify. And even if a deal does come out of Vietnam, there’s no guarantee that it would mean much — or be beautiful for the U.S. For example, after Singapore, Trump said North Korea had committed to denuclearization, but just a few months ago, North Korea said it would not get rid of its nuclear weapons program until the U.S. removed some of its military capacity in the Korean peninsula.

Nevertheless, symbols matter in politics, and real progress could be made in Vietnam, as it has been made in U.S.-North Korea relations already. Kang suggested that North Korea could begin to open its economy and its country and to take some steps down the denuclearization path, perhaps promising to shut down the nuclear reactor site Yongbyon.

“No matter what, Hanoi is not the final step,” he said.

Trump to touch down in Vietnam today