WASHINGTON — As President Donald Trump flew to Hanoi, Vietnam, this week, White House press secretary Sarah Sanders had a surprise announcement: Trump and Kim would meet earlier than expected, at a dinner on the first evening. The late announcement led skeptics to describe the dinner as an attempt to overshadow Michael Cohen's embarrassing testimony about his work for Trump. But the last-minute dinner raised unexpected challenges. The two sides apparently struggled over the menu, with the White House pressing for simpler fare.

Even as a first-time novelist, I know this is called "foreshadowing."

The dinner went well enough, according to reports, but during the meeting the next day, everything collapsed. Trump and Kim departed early, leaving behind a carefully prepared lunch of foie gras, snowfish and candied ginseng. Members of the U.S. delegation were seen grabbing burgers.

Trump and North Korean Foreign Minister Ri Yong Ho both gave news conferences after the talks broke down. While they characterized the cause of the collapse in different terms, the basic outlines are clear enough. Everyone seems to agree that North Korea offered to close its nuclear facilities at a place called Yongbyon. Yongbyon is not North Korea's only source of fissile material for nuclear weapons, but it is an important site. In exchange, North Korea demanded what it described as "partial" relief from sanctions imposed by the United Nations Security Council. Trump objected, insisting that Kim would have to close other sites involved in the production of nuclear weapons before any sanctions could be lifted.

South Korean and U.S. officials have been misrepresenting public statements by Kim Jong-un

This outcome comes as a surprise. North Korean officials have been clear for months that they were willing to close Yongbyon in exchange for "corresponding measures' and - working with China and Russia - North Korea has been making it clear that those corresponding measures included sanctions relief. For months, it has been clear that North Korea was offering to close the nuclear facilities at Yongbyon and only those facilities. Other facilities, including a uranium enrichment plant near Kangson that my colleagues and I helped identify, were never on the table.

So why did U.S. officials think they were? For some months, I and others have been concerned about the degree to South Korean and U.S. officials have been misrepresenting public statements by Kim Jong-un. Those misrepresentations naturally raised questions about whether the administration's characterization of Kim's private comments was accurate and, if not, whether those officials were fooling us - or themselves.

For example, in a recent speech at Stanford, the Trump administration's special envoy for North Korea, Stephen Biegun, flatly asserted that North Korea had privately offered to close much more than just Yongbyon. His reasoning was strange - he explained that he believed North Korea was offering to close facilities beyond Yongbyon because "in describing to us their commitment to dismantle and destroy their plutonium and uranium enrichment facilities, the North Koreans have also added the critical words "and more." " At the time, this seemed to be an absurdly specific reading of a vague phrase. "And more" might mean so many things, or even nothing at all. But Biegun was apparently willing to fly Trump halfway around the world to Hanoi based on the idea that it represented a commitment to declare other secret facilities and abandon them.

Hanoi confirms what we might have imagined all along. Biegun was wrong. When the United States tried to press North Korea on this imaginary commitment to close "more" locations, the North Korean position remained the same as it has been since the fall: Sanctions relief in exchange for the shutdown on the nuclear facilities at Yongbyon and no more.

So Trump walked away. Trump himself sounded a hopeful note in his news conference, expressing his belief that "eventually we'll get there." Ri, the North Korean foreign minister, was far dourer, stating that North Korea's position would "never be changed," even if the United States proposed more negotiations. One of his deputies was more scathing. "Chairman Kim got the feeling that he didn't understand the way Americans calculate," Choe Son Hui told reporters. "I have a feeling that Chairman Kim may have lost the will" to continue negotiations.

What really happened in Hanoi was that Trump and Kim finally confronted the fundamental difference in their expectations, a difference many people who have studied the nuclear situation on the Korean Peninsula have warned about from the start.

Trump continues to assert that pressure has brought Kim Jong-un to the verge of abandoning his nuclear weapons, or "denuking," as Trump calls it. For Trump, Kim must give everything up and then accept Trump's promises of generosity.

Kim, by contrast, believed that the successful tests of thermonuclear weapons and ICBMs that can strike the United States have forced Trump to come to him, offering to end the sanctions. To make Kim's rule and his possession of the bomb more palatable, he has declared an end to nuclear and missile tests and is willing to offer a variety of gestures that mimic disarmament. The world must live with North Korea's bomb, but Kim won't rub it in anyone's face.

One side must give on the core question.

This is not a difference in perspective that can be fudged with careful phrasing. One side must give on the core question of whether North Korea's isolation can end before it undergoes nuclear disarmament. Since it would be utter madness to try to topple a nuclear-armed dictator, it seems obvious which side should yield: Trump and the national security community in Washington must abandon the broad, bipartisan consensus that North Korea must disarm before anything else. This is, after all, what nuclear weapons do. They trap us together with our enemies, like scorpions in a bottle, creating a shared danger that compels us to work together to advance our mutual interest in survival.

When Richard Nixon opened relations with China, he did not demand that Mao Zedong abandon the bomb. Mao would simply have refused, and the historic moment would have been lost. Trump faces the same fundamental choice. If he does not accept the reality that we now live with a nuclear-armed North Korea, then we are doomed to the collapse of negotiations, and perhaps even a return to the terror of 2017, punctuated with Trump's taunts of Rocket Man and boasts about whose button is bigger. (My novel is about what that world might look like. I don't want to spoil it for you, but the title gives it away: "The 2020 Commission Report on the North Korean Nuclear Attacks on the United States.")

Are negotiations dead? It's too early to say. But it is clear that Kim anticipated this moment. During his annual speech on New Year's Day, he stated directly that negotiations would collapse if the United States "persists in imposing sanctions and pressure against our Republic." Without sanctions relief, he threatened, "we may be compelled to find a new way for defending the sovereignty of the country and the supreme interests of the state . . ."

What that new way might be, he did not specify. But now that Trump and Kim have left the snowfish to rot in Hanoi, we're about to find out.