President Moon Jae-in leaves for Pyongyang on Tuesday for talks with North Korean leader Kim Jong-un. It is Moon’s first visit to the North Korean capital, but it is not evoking as much excitement as previous visits by former South Korean leaders Kim Dae-jung and Roh Moon-hyun.

It is partly because two of his predecessors, including his former boss Roh, have already made precedents and partly because he has already met Kim twice at the truce village of Panmunjom.

But perhaps a bigger reason for the relatively subdued mood is that Moon will be traveling to Pyongyang with a heavy sense of responsibility because the visit comes at a time when the core part of the peace process he and Kim initiated through their two previous meetings is at an impasse.

The core part – denuclearizing the North – has hit a snag due to confrontation between the US and the North, which has largely eclipsed the initial anticipation and excitement Kim and US President Donald Trump generated through their historic meeting in June.

Therefore, Moon’s trip to Pyongyang, which may be followed by a second meeting between Trump and Kim, must help reinvigorate the denuclearization process.

Moon and his aides said that Moon’s three-day visit to Pyongyang would focus on two agenda: denuclearization and development of inter-Korean relations. The latter is centered on reduction of military tension – especially along the border – and economic cooperation.

For now, economic cooperation is an area of concern, primarily because of the harshest-ever international sanctions imposed on the North. Concerns have already been raised at home and abroad that inter-Korean cooperation programs and joint projects pushed by Moon could involve North Korean entities and individuals blacklisted by the sanctions.

It is against this backdrop that Cheong Wa Dae’s decision to have the heads of the nation’s four top conglomerates – Samsung, Hyundai Motor, SK and LG – accompany Moon on his Pyongyang trip has stoked public criticism. Moon needs to minimize the conglomerates’ involvement in projects that might tamper with sanctions, which could put the global businesses of the conglomerates in peril.

Given recent developments, Moon and Kim are expected to have little difficulty pulling off some agreements to end hostility and reduce military tension between the two sides. That was a major part of the Panmunjom Declaration they signed after their first meeting in April.

Last week, the two Koreas opened a joint liaison office in Kaesong, where they operated an industrial park, and senior military generals held talks to lay the basis for agreement between Moon and Kim.

The two leaders are likely to agree that the two sides withdraw guard posts from the Demilitarized Zone, jointly excavate remains of servicemen who died in the DMZ area during the Korean War and designating the Joint Security Area that houses Panmunjom as a no-arms zone. The two sides also have discussed suspension of live-fire drills and designation of joint fishing zones in the West.

These plans are all welcome. The good point is that basically, they have little to do with the sanctions, and tension-reducing measures are necessary regardless of the progress on denuclearization. They would not only promote the peace mood but also prevent accidental skirmishes.

But any agreement of the Moon-Kim talks would be simply meaningless if the two fail to move the denuclearization forward. Indeed, would it be meaningful for the two sides to get some guard posts and arms out of the DMZ, while the North being allowed to keep nuclear bombs that can decimate huge numbers of people with just one stroke?

Regarding denuclearization, what’s essential is getting Kim’s action plans – no more commitments and promises – on declaring an inventory of nuclear materials and facilities and opening them to international inspection. Then Moon would be able to move forward on his plans to get both Kim and Trump a deal on the declaration of the end of the Korean War.

Negotiations with the North have always been tricky. More importantly, many agreements made in the past, including those made by Kim’s father and the two late South Korean leaders in Pyongyang, have failed to hold. This is a lesson Moon should keep in mind before getting on board Air Force One.