It now appears that the summit meeting between US President Donald Trump and North Korea’s leader Kim Jong-un might still be held on schedule after all. It is possible that Pyongyang’s polite reply to Trump’s surprise cancellation of the summit was enough for Trump to give the meeting another shot.

But should a summit take place, either on its target date of June 12 or beyond, the two parties should better prepare themselves for what they want to come out of it. In pulling out of the summit just as fast as he surprised the world by accepting it, Trump perhaps acted impulsively without considering where it might end up. A summit of this scale should be preceded by months of diplomacy. Trump and his team needed to put in the difficult and tedious preparation needed before the meeting. By the time the last step is reached, no aspect of the deal should remain in doubt. What should be left are the handshakes and other pleasantries, capped by whatever documents are to be signed in front of the cameras. What Trump did instead was immediately announce he was willing to meet directly with Kim, jumping straight to the last stage, that of North Korean denuclearization.

But Trump was never likely to get Kim to agree to a complete, immediate denuclearization. The two must begin the process toward a more constructive summit, with more realistic outcomes.

If one was to pin down exactly when and why the summit derailed, look no further than when the US administration, in the form of National Security Advisor John Bolton and later Vice President Mike Pence, started talking about the Libya model in which Muammar Gaddafi gave up his nascent nuclear program only for him to be killed by Western-backed rebels a few years later. Bolton and Pence demanded full, Libya-like denuclearization, signaling it’s that or nothing.

The thought of meeting the same fate as Gaddafi who was dragged through the streets, mutilated and murdered, was enough for Kim to push back on the nightmare scenario that he might be next, making it clear that denuclearization was not on the cards, forcing Trump to call the whole thing off. It is precisely to avoid this fate that North Korea was determined to cling to its nuclear weapons.

This time, there should be no mention of Libya or Gaddafi. Better to negotiate for slow steps toward denuclearization while providing North Korea with the incentives to follow through on nuclear elimination.

Because both have left the door open, the odds remain that Trump and Kim want the meeting as badly as ever, and will jump at the chance to reschedule it. Kim made a series of concessions in his bid to sit down with Trump — stepping across the DMZ to meet his South Korean counterpart, signaling a willingness to accept a US military presence on the Korean Peninsula; unilaterally announcing an end to nuclear testing, and the dismantling of some testing facilities and releasing three American hostages. Kim also needs the US to lift sanctions strangling his country.

As for Trump, his cancellation may be for the better. He built expectations that were too high, tempted by premature talk of Nobel prizes and succeeding where all previous administrations had failed in denuclearizing the Korean Peninsula.

From the start, the Trump administration wanted something North Korea was never going to give: handing over its entire nuclear arsenal. That’s why America’s stated goal of denuclearizing the peninsula was out of reach.

In this sense, no deal might be better than a bad one. So it’s better that Trump canceled the meeting, at least for now. Nuclear diplomacy takes time and hard work. In the run-up to the summit, neither was evident.