Only days after a South Korean delegation returned from North Korea with a potential diplomatic opening to address the peninsula’s slow-motion nuclear crisis, President Donald Trump agreed to meet with Kim Jong-un sometime before the end of May 2018. The upcoming summit between Trump and Kim will be the first time that a sitting U.S. president has met with the ruler of North Korea, and marks a major opportunity for a reduction of tensions between the two countries that ran dangerously high last year.

This is an important moment for the United States. The key weakness of the administration’s approach was its lack of diplomatic engagement with North Korea that would offer a peaceful path toward denuclearization.

Now that South Korea’s diplomatic outreach has created an opening for U.S.-North Korea negotiations, the Trump administration would be foolish not to give talks a chance. However, it would also be prudent for the United States to enter negotiations with some suspicion about North Korean intentions and goals.

The key question hanging over North Korea’s offer to talk is what Kim Jong-un will ask from the United States in return for progress on denuclearization. The strategic rationale behind North Korea’s nuclear weapons program is the insurance they offer against regime change. Therefore, Kim will not give up his nuclear weapons unless he is confident that his regime — and he — will survive without them. Reassuring Kim will likely require the United States to soften its military and economic pressure against North Korea, which the latter refers to as the “hostile policy.”

In other words, the peaceful denuclearization of North Korea will not be a freebie for the United States. While it is too early to tell what specific demands Kim will make in the upcoming summit, likely “asks” include lifting bilateral and multilateral sanctions, withdrawing U.S. troops from South Korea, and the end of the U.S.-South Korea military alliance.

Trading away the U.S.-South Korea military alliance in exchange for a denuclearized North Korea would be a bitter pill for Washington to swallow, but such a trade-off would likely be necessary to reassure Kim that his regime will survive without nuclear weapons. This trade-off would diminish U.S. influence in the region to a degree, but the risks of armed conflict between North and South Korea would not increase as a result. Seoul’s strong economy and steadily improving conventional military capabilities mean that it would not be defenseless should the alliance cease. North Korea would still possess a large conventional military, but without nuclear weapons it would not have a clear enough advantage over South Korea to invade and reunify the peninsula through military force.

The Trump administration could avoid the trade-off entirely by adopting an ultimate objective of deterring the use of a nuclear weapon by North Korea rather than denuclearization, but the administration seems intent on keeping denuclearization as its end goal.

Even if the proposed U.S.-North Korea denuclearization talks fail to reach a final settlement, the Trump administration can still reap other benefits by sitting down to talk. According to the South Korean negotiators, Kim said that the North would not test ballistic missiles or nuclear weapons so long as it is talking to the United States. While this would not prohibit North Korea from working on new missile and nuclear weapons technology, a testing moratorium prevents North Korea from gathering important information about its capabilities that it can only obtain through tests. Moreover, a moratorium would reduce the tension generated by such tests and the reactions to the tests. In this regard, the Trump administration should not let the perfect be the enemy of the good. Getting a pause in North Korean missile and nuclear testing would be a win for the United States and its allies even if talks ultimately break down.

Entering into negotiations with North Korea is the right choice for the United States, but the Trump administration should be somewhat circumspect about what talks can achieve. Kim Jong-un is rational, but rationality does not mean he is trustworthy. The recent history of U.S.-North Korean relations is replete with broken promises, failed deals, and frustrating negotiations that ultimately lead nowhere. The Trump administration should go into negotiations with this history in mind and manage expectations about what negotiations can achieve, but it should not be afraid to begin talks and see what happens.

The United States should be cautiously optimistic about the Trump-Kim summit. Direct talks will be good for reducing tensions in the short run, but the summit will be just the start of a long and difficult process that could easily fall apart. The most important short-term task for the Trump administration is assembling a diplomatic team to attend the summit. Trump’s diplomatic bench is woefully shallow in general and the retirement of Joseph Yun from the State Department and withdrawal of Victor Cha’s nomination for ambassador to South Korea leaves the administration short on Korea expertise in particular.

Achieving a peaceful and verifiable denuclearization of North Korea through diplomacy is a tall order for the Trump administration, and it will face many challenges as it goes down this war. However, so long as denuclearization is the United States’ ultimate goal, diplomacy is a far better option than going to war to denuclearize the North by force.