With less than a week to go before he sits down with his South Korean counterpart, North Korean leader Kim Jong Un made an impressive set of declarations. Following a meeting of the Workers’ Party of Korea’s Central Committee this week, Kim declared, among other things, that North Korea would shut down its nuclear testing site—known as Punggye-ri—and stop testing its intercontinental-range ballistic missiles (ICBMs).

If there’s one thing the North Koreans are good at, it’s messaging and propaganda. Kim’s announcement was published in the Korean Central News Agency (KCNA), North Korea’s state-run news media. Importantly, KCNA is intended for consumption by the world outside of North Korea’s borders.

With momentum in full-swing toward the summit with Moon Jae-in next week and an eventual, still unscheduled, historic summit planned with American President Donald Trump—the first-ever sit-down between two sitting leaders of North Korea and the United States—Kim has all the incentives in the world to make sure that these meetings come together as planned.

If the odds of a Trump-Kim summit stood at 50-50 before Friday’s announcement, they’ve now increased considerably. In fact, Kim has increased the costs considerably for Trump of backing out of a summit.

Without equivocating, it’s fair to say that both the declarations on nuclear testing and on halting the tests of ICBMs are significant concessions. Specifically, Kim announced that North Korea will “discontinue nuclear testing” and that the Punggye-ri site will be “dismantled to transparently guarantee the discontinuance of the nuclear test [sic].” On ICBMs, Kim simply said that no “inter-continental ballistic rocket test-fire” would take place after April 21, 2018.

While significant, we shouldn’t be fooled into thinking that these concessions are being made out of a position of weakness or as a necessary show of bona fide goodwill to South Korea and the United States before the upcoming summits. Kim’s rationale for doing away with the nuclear test site was to underline that North Korea had already successfully come up with the nuclear weapons designs it needed.

Though unverifiable, there’s no reason to believe that Kim’s reasoning is flawed or overstated. North Korea has claimed, after its fifth and sixth nuclear tests respectively, to have designed and tested a standardized and compact fission bomb and a city-busting thermonuclear bomb.

In fact, North Korea’s sixth nuclear test in September 2017 may have been the largest man-made explosion on Earth since a Chinese thermonuclear test in 1992. Based on seismic readings, that test was also considerably more powerful than any of the devices India and Pakistan—two other nuclear weapons possessors—tested over the course of their six tests each. (Neither country has conducted more test since.)

The message on nuclear-testing is clear: Kim Jong Un feels he’s got a pretty good bomb design—two of them, in fact. He’s confident that he can place them on missiles that are credibly threatening enough to give North Korea a powerful deterrent against attack and invasion. Even as President Trump lauds Kim’s decision to “suspend all Nuclear Tests and close up a major test site” on Twitter, this context is critical.

The ballistic missile moratorium is welcome news, too, but it is not a sign that the threat North Korea poses to the United States will evaporate. Yes, it’s true that North Korea has now shown that it can reliably—let’s say around 50 percent of the time—launch an ICBM capable of delivering a warhead that can survive the heat and stress of atmospheric re-entry. Yes, it would probably need further testing to validate that capability. But despite this, North Korea’s three ICBM tests last year, of two different designs, have given it a credible capability.

Freezing ICBM launches, though, will be seen as a bona fide gesture in the United States, where many observers—including yours truly—had suggested that such a freeze could have been a productive outcome of a Trump-Kim summit. Now, North Korea has given this up in advance of a summit. For Kim Jong Un, the big prize all along has been a summit with a sitting U.S. president; the moment he walks into that room with Trump and sits down beside him for talks, nuclear world leader to nuclear world leader, he’ll have a huge propaganda coup.

Before getting carried away with Kim’s ICBM testing pause, though, the Trump administration should be ready to deal with the circumstances that brought down the Obama administration’s last serious attempt at diplomacy with North Korea. In 2012, the two countries announced a fairly modest agreement on Feb. 29: North Korea would cease missile launches and nuclear testing activity in exchange for food aid and other carrots.

The ink had hardly dried before North Korea announced that it would be launching a satellite—a move that it framed as a peaceful, non-threatening use of civilian technology. Of course, that wasn’t acceptable to Washington. Turns out, the technology between ICBMs and satellite launchers is pretty similar—at least on the way up. The first ICBM in the world, the Soviet Union’s R7 Semyorka, in fact, went the other way: It was designed to deliver nuclear payloads, but was then modified to deliver Sputnik-1 into orbit. (The R7 ended up seeing far more use as a satellite launcher than an ICBM.)

The February 2012 agreement fell apart when the North Koreans kept to their word and launched a satellite launch vehicle. This year, we could see a repeat of that play out. A small but convincing body of evidence points to ongoing work in North Korea toward a more capable satellite launcher based on the engine technology underlying the Hwasong-15 ICBM—North Korea’s most powerful missile. Is the Trump administration ready to deal with North Korea’s rationale for satellite launches? Will these be brought up at a summit with Kim?

In the end, Kim’s declarations are designed to keep Trump interested in the summit and they seem to have worked. The president has already enthusiastically declared that he looks forward to the summit with Kim. But the administration needs to start sweating the details on how it’ll take what Kim’s given up here and turn it into a winner of a deal—one with some degree of verifiability.

The nuclear test site concession seems big, but Kim’s already pointed out that it’s something of a nothingburger given that North Korea’s done with its bomb designs. Missile moratoria, meanwhile, are meaningless if they’re self-enforced. North Korea’s last self-enforced moratorium in 1999 came crashing down in 2006. Finally, the big D-word—denuclearization—is nowhere to be seen in North Korea’s Friday statement.

Even as the odds of a summit between Trump and Kim rise, it’s far from clear that Washington has it’s expectations calibrated properly or that this administration is sweating the technical details that matter. If Trump shows up to a meeting with Kim expecting the North Korean leader to turn over the keys to his nuclear program, he’ll leave sorely disappointed—maybe even furious and inclined toward war.

But there’s no reason for that. A look at history and at the state of North Korea’s nuclear and missile programs today make clear what Kim is and isn’t willing to do. Trump and his advisers should take heed before the summit.