The success of the inter‐Korean summit provides insight into both of these possibilities.
The text of the Moon Jae‐in‐Kim joint declaration suggests that denuclearization will be the primary topic of the upcoming Trump‐Kim summit. Denuclearization receives very little attention relative to other objectives in the declaration. For example, the joint declaration’s section on alleviating military tensions mentions specific confidence‐building measures that both South and North Korea will implement such as military‐to‐military talks and removing propaganda loudspeakers from the border area. By comparison, the section on denuclearization does not mention any similar short‐term measures beyond recognition of Kim’s decision to close the Punggye‐ri nuclear test site and stop tests of intercontinental ballistic missiles .
Therefore, the Trump administration will likely take the lead on denuclearization issues, while inter‐Korean relations will focus on achieving a peace treaty to end the Korean War and increasing economic and people‐to‐people exchanges.
Yet denuclearization will be a difficult task for the Trump administration. North Korea developed nuclear weapons as an insurance against invasion and regime change, which means the possession of nuclear weapons is essential to Kim’s survival. It is unlikely that Kim will give up his nuclear weapons without significant U.S. concessions that produce a similar degree of insurance. Pyongyang has stayed tight‐lipped about what concessions it wants, but they will most likely include significant sanctions relief and reductions or changes in U.S. military forces in South Korea.
Accepting concessions may be unpalatable if Trump goes into the summit believing that his “maximum pressure ” approach forced Kim to the table. If the United States believes that its position is stronger than North Korea’s then it may be unwilling to make big concessions unless the North takes big steps towards denuclearization first. However, Kim is probably entering the summit with a very different understanding of his position. In an April 20th plenum speech to the Workers’ Party of Korea, Kim claimed that North Korea had successfully completed a nuclear deterrent, suggesting that his charm offensive reflects confidence rather than weakness . These differing perceptions of advantage and confidence could make the Trump‐Kim summit very difficult if either leader digs in their heels and is unwilling to accede to the others’ demands.
Additionally, the inter‐Korean summit raised the costs of a Trump‐Kim summit failure by underscoring that failure would leave the United States as the odd man out in the region. In 2017, the Trump administration was able to build a strong regional consensus for cracking down on North Korea. Japan and South Korea joined the United States in tightening unilateral sanctions on Pyongyang and the United States pushed for closer military cooperation with both countries . Washington was also able to get China’s support for U.N. Security Council sanctions, producing a very strong sanctions regime against North Korea. Getting Seoul, Tokyo, and Beijing moving in the same direction was an important feature of the Trump administration’s approach to North Korea.
A failed Trump‐Kim summit would put the United States at odds with many of the other regional states that it marshaled to its position last year. Japan would stick by the United States if the Trump‐Kim summit collapses, because Tokyo is skeptical of diplomacy with North Korea , but the United States would likely lose support from China and South Korea.
Beijing regards tougher sanctions as a tool to get Pyongyang back to the negotiating table, which has now happened. Moreover, the U.S.-China relationship took a serious downturn this year in large part due to Trump’s action on trade policy. China has met its primary political objective of getting North Korea to the negotiating table and has a worsening relationship with the United States. Beijing therefore faces little incentive to continue going along with the Trump administration’s “maximum pressure” approach should the Trump‐Kim summit break down.
South Korea would also be hard‐pressed to support further U.S. sanctions and pressure against North Korea if the Trump‐Kim summit fails. President Moon made diplomacy with North Korea an important part of his political agenda and the success of the inter‐Korean summit makes engagement even more attractive. Indeed, the inter‐Korean summit and Moon himself are very popular among the South Korean people and Moon’s party is poised to gain influence in upcoming local elections in June . Once the two Koreas begin implementing the military confidence‐building measures and people‐to‐people exchanges laid out in the joint declaration, it will be very difficult to reverse momentum on inter‐Korean engagement.
Trump has his work cut out for him. If the inter‐Korean summit truly is a success, it means that the costs of Trump’s summit ending up a failure are magnified. If Trump wants to the rest of the region to keep working with the U.S., he has to remember that the U.S. position in this negotiation isn’t as strong as he’d like it to be.