SEOUL -- Despite the meticulous preparations by North and South Korea ahead of Friday's historic summit, one central question has yet to be decided: whether the two leaders can reach an accord on denuclearization.
Unusually, the matter was not sorted out in working-level talks ahead of the meeting and will instead be negotiated directly between the leaders, according to Im Jong-seok, South Korean President Moon Jae-in's chief of staff. The degree to which they will agree on denuclearization -- which North Korean leader Kim Jong Un has expressed a willingness to consider -- and the language to be used in a planned joint statement have yet to be decided, Im told reporters Thursday.
"It's a moment of truth," he said.
Kim told a visiting South Korean delegation last month that Pyongyang would have no reason to maintain its nuclear arsenal if his government's survival were guaranteed. He sent a message to U.S. President Donald Trump that direct talks could prove very fruitful. The two leaders are expected to meet by early June.
The key challenge is that Pyongyang's idea of what the process entails differs from the view in Washington and Seoul. While the U.S. seeks an end to North Korea's nuclear program, the North insists on denuclearization of the entire Korean Peninsula.
North Korea seems to believe that the U.S. military still has atomic weaponry in South Korea, despite the announced withdrawal of all American tactical nuclear weapons from the country in 1991. A 2016 statement by a Northern spokesman demanded that Washington disclose and dismantle all its nuclear weapons on the peninsula, along with their bases, and withdraw any troops authorized to use those capabilities.
The two sides remain at odds on how to go about denuclearization as well. Visiting Beijing last month, Kim told Chinese President Xi Jinping that the nuclear issue could be resolved through "gradual, simultaneous" measures by both sides. This seems of a piece with Pyongyang's usual line of seeking concessions in exchange for each incremental step it takes.
Washington, meanwhile, is expected to consider lifting economic sanctions and normalizing diplomatic relations only after the North's complete, verifiable and irreversible denuclearization.
U.S. National Security Adviser John Bolton has advocated a "Libya-style" scenario. In 2003, Libyan leader Moammar Gadhafi declared after secret talks with the U.S. and U.K. that his country would surrender all weapons of mass destruction, including nuclear weapons. Even then, Tripoli established diplomatic relations with Washington only after International Atomic Energy Agency inspections and two and a half years of negotiations.
But North Korea is not eager to follow this example, given that Gadhafi was overthrown and killed in 2011.
Nevertheless, Moon has expressed optimism about the outlook for an agreement. "I don't think there is a difference between our conceptions of denuclearization," he told executives of South Korean news organizations last week.
Denuclearization was not a focal point of the two previous inter-Korean summits, which centered on reunification and economic cooperation.
North Korea used the first meeting -- held in June 2000 between North Korea's Kim Jong Il and South Korean President Kim Dae-jung -- to secure vital economic support during severe food and energy shortages, as well as to gain an opening for diplomacy with the U.S.
The second summit in October 2007, between Kim Jong Il and South Korean President Roh Moo-hyun, produced a plethora of joint economic projects and a proposal for talks with the U.S. and China toward a peace treaty to formally end the Korean War. The two sides also pledged to resolve the nuclear issue by implementing a 2005 deal reached through the six-party talks framework.
But the meeting failed to restrain the North's nuclear and missile development, in part because Roh, whose term would end the following February, lacked time and leverage to see the agreement through. Moon, who played a leading role in arranging the second summit as Roh's chief of staff, probably sought a meeting with Kim Jong Un so early in his own tenure in part to avoid repeating this mistake.