The historic meeting between President Donald Trump and North Korean leader Kim Jong Un is over — and Trump thinks it went really well.

During a lengthy press conference, Trump hailed the historic summit on Tuesday as “very successful,” and praised Kim as having a “great personality.” He also called the agreement that they signed the start of a new era in North Korea’s relationship with the world. “We’re prepared to start a new history, and we’re ready to write a new chapter between our nations,” the US president added.

The agreement, in which both countries commit to working toward peace and “complete denuclearization” of the Korean Peninsula, reduces tensions between the US and North Korea to the lowest they’ve been since Trump assumed office.

It’s a remarkable development for two countries that were threatening to launch a nuclear war against each other just months ago — a nightmare scenario that military analysts said was a real possibility.

But despite the pomp and circumstance, experts say that Trump’s agreement with Kim is more of a symbolic achievement than a substantive one. They’re also concerned that Trump has conceded far too much to Pyongyang without receiving enough — if anything — in return.

The agreement’s language is apparently more vague and less demanding of North Korea’s denuclearization program than previous agreements the US has had with the country. Some see Trump’s decision to halt joint US-South Korean military exercises as a huge and unreciprocated giveaway to Kim.

“Unfortunately, we do not know if Kim has made a strategic decision to denuclearize and it is unclear if further negotiations will lead to the end goal of denuclearization,” Anthony Ruggiero, a senior fellow at the conservative Foundation for Defense of Democracies think tank, told Reuters. “This looks like a restatement of where we left negotiations more than 10 years ago and not a major step forward.”

The US-North Korea agreement is extremely vague

The agreement that Trump and Kim made consists of four main points:

The United States and the DPRK commit to establish new US-DPRK relations in accordance with the desire of the peoples of the two countries for peace and prosperity. (DPRK stands for the Democratic People’s Republic of Korea, the formal name of North Korea.) The US and the DPRK will join their efforts to build a lasting and stable peace regime on the Korean Peninsula. Reaffirming the April 27, 2018, Panmunjom Declaration, the DPRK commits to work toward the complete denuclearization of the Korean Peninsula. The US and the DPRK commit to recovering POW/MIA remains including the immediate repatriation of those already identified.

The language is vague enough that the agreement really seems to be about setting the stage for more talks in the future. But experts point out that the framework of the agreement is softer on North Korea than previous deals.

“Each of the four main points was in previous documents with NK, some in a stronger, more encompassing way,” Bruce Klingner, a former CIA deputy division chief for Korea, tweeted on Tuesday. “The [denuclearization] bullet is weaker than the Six Party Talks language.”

In September 2005, North Korea formally agreed to abandon “all nuclear weapons and existing nuclear programs” in exchange for energy assistance from countries, including the US, in the so-called Six Party Talks (which included China, the United States, South Korea, Japan, and Russia). But in 2009, amid disagreements over technical details related to verification, North Korea walked out on the talks.

Trump offered Kim a big concession

Trump also announced other agreements with North Korea at the press conference.

The biggest policy change the president unveiled was that the US will halt joint military exercises with South Korea, which has served as a crucial way for the US to put military pressure on North Korea. This announcement came as a surprise for a number of reasons.

First, it appears that Trump made the concession without getting anything remotely comparable from Kim in return. Second, he framed it as a financial issue, pointing out that cutting back on the drills will save a “tremendous amount of money.” In the process, he criticized US ally South Korea for not pulling its weight. “South Korea contributes [to the military exercises], but not 100 percent, which is a subject that we have to talk to them about,” the president said.

Analysts were shocked by the statement. “Apparently jet-fuel is so expensive, it’s worth casting aside a 60-year ally and friend,” Robert Kelly, a professor at South Korea’s Pusan National University, said.

It seems that Trump also surprised South Korea with his decision to cancel the joint exercises. “At this moment, we need to figure out President Trump’s accurate meaning and intention,” South Korean President Moon Jae-in’s office said in a statement on Tuesday.

Trump also indicated that he’d like to eventually close down US military bases in South Korea. “We have 32,000 soldiers in South Korea. I would like to be able to bring them back home. That’s not part of the equation. At some point, I hope it would be,” he said.

If that happens, it would be another major concession to Pyongyang because it would make North Korea feel far safer to have US military power gone from the Korean Peninsula.

Experts also point out that Trump declined to criticize North Korea’s terrible record on human rights, and had no details to offer on how the US would verify that North Korea was in fact going to take steps toward denuclearization.

Trump did announce one concession by North Korea — he said Kim had promised to destroy a missile engine testing site “soon.”

But MIT nuclear expert Vipin Narang criticized the testing site destruction as a “measly” giveaway and said it was easy to rebuild. “I’m totally confused about the art of this deal,” he tweeted.

It’s good that the US and North Korea are talking. But this isn’t a promising start.

All things considered, experts say, the summit represents a positive development for the US-North Korean crisis. The two countries are no longer swapping insults and promising to turn each other into ashes. Things could have gone very poorly — If Trump had felt that Kim was offering nothing that he liked, and the two leaders were unable to reach an agreement, that could have caused the chance of war to rise considerably.

But at the same time, it would be inaccurate to describe it as a resounding success.

Kelsey Davenport, the nonproliferation policy director at the Arms Control Association, said that the summit was “mediocre at best” because it didn’t break any new ground compared to past frameworks for denuclearization that the US and North Korea have agreed to.

And Richard Nephew, a State Department official during the Obama administration and a scholar at Columbia University, tweeted that the agreement between the US and North Korea was “very thin,” but that “this is what I fully expected and have been defining as my best case scenario.”

Others across the political spectrum felt that Trump had failed to live up to his much-touted prowess as a dealmaker. Kelly, the scholar at Pusan National University, said that Trump’s giveaways in return for little amount to one clear point: “Trump is a dove on North Korea.”

And it’s still unclear where things will go from here. “It is far too early in the process for Trump to declare success,” Davenport said in an email. “The true test of success is whether the follow-on negotiations can close the gap between the United States and North Korea on the definition of denuclearization and lay out specific, verifiable steps that Pyongyang will take to reduce the threat posed by its nuclear weapons.”

So it remains to be seen whether North Korea and the US will continue to have cordial discussions — and whether this summit will be all for show, or yield something more substantial. In the meantime, at least we’re not on the brink of nuclear war.