Could North Korean leader Kim Jong Un finally be willing to talk to the United States about giving up nuclear weapons? That is the message apparently emerging from Pyongyang this week, after Kim told visiting envoys from South Korea that he was ready to halt North Korea's nuclear weapons program in exchange for talks with the United States.

The United States has long said that it would not enter into talks with North Korea unless denuclearization was put on the table. Over the past year, North Korea has made considerable advances in its weapons program, leading to widespread talk of a possibly devastating conflict with the United States.

For many watching the tension on the Korean Peninsula with apprehension, Kim's apparent outreach on Tuesday was a positive sign. Even President Trump, who has taken an unusually combative tone in his discussion of North Korea since entering office last year, took to Twitter to describe it as “possible progress,” noting that “a serious effort is being made by all parties concerned.”

But Trump also cautioned against “false hope” — and although he has spoken skeptically of the benefits of diplomacy with North Korea in the past, he is not the only one who is apprehensive about the future of talks. Here are three unresolved questions about negotiations with North Korea:

What exactly is North Korea offering?

The details of North Korea's offer didn't come directly through Pyongyang but via a South Korean delegation that visited the North this week.

The leader of that delegation — Chung Eui-yong, South Korea’s national security director — told reporters Tuesday that the North was open to “candid” talks about denuclearization and that it would suspend missile and nuclear tests while dialogue was underway. According to Chung, Kim said his country would be willing to abandon its nuclear weapons program if its national security and leadership could be ensured.

This clearly would be a big move from North Korea. In the past, it has insisted that its nuclear weapons, which it has called its “sword of justice,” were not up for discussion with the United States. Although some analysts have discerned subtle signs that Pyongyang could be more flexible than it let on, this would be the first time that North Korea has unequivocally put denuclearization on the negotiating table.

Or did it? We have to remember here that all this talk has come via the South Koreans, who are led by President Moon Jae-in, a vocal supporter of dialogue with North Korea. North Korean state media (admittedly not known for its clarity) has spoken of the meetings in Pyongyang with Chung's delegation only in vague terms.

As such, it remains to be seen exactly what North Korea is putting on the table. And even if it sticks to the account put out today and halts weapons testing, this doesn't necessarily mean that its weapons program itself is dormant — indeed, just Monday, 38 North released satellite imagery that appeared to show signs that a North Korean reactor had resumed production of plutonium for nuclear weapons.

What is the United States willing to give in return?

There is a remarkable detail in the news today: A senior South Korean official told the Associated Press that Kim understood that annual military drills between the United States and South Korea would probably take place at a similar scale as in previous years but that he hoped they might be scaled down in the future.

These military exercises have long been a sticking point for North Korea, which views them as a precursor to an invasion. The much-maligned “freeze for freeze” negotiations idea pushed by China and Russia had suggested that the drills could be halted in exchange for North Korea halting its weapons testing.

But if North Korea accepts that the military exercises will go ahead yet freezes its weapons testing, what is it seeking in return? In the long term, this is the question that worries many North Korea analysts.

“The biggest hurdle will be agreeing on the ultimate outcome of U.S.-North Korea talks and agreeing on a price tag for Pyongyang's nuclear arsenal,” said Duyeon Kim, a fellow at the Korean Peninsula Future Forum. “In past negotiations, the North's willingness to eventually abandon its nuclear weapons has been contingent upon an end to the U.S.-South Korea alliance and withdrawal of U.S. troops from Korea.”

One clear possibility in the short term is that Pyongyang would seek relief from sanctions, which are finally starting to take a bite out of North Korea's economy. However, many in Washington will be skeptical of this trade-off, arguing that the North has used past negotiations for temporary economic benefit.

Can negotiations really lead to a deal — and can that deal really last?

There have been plenty of attempts at negotiations with North Korea before. The deals these talks produced, such as the 1994 “agreed framework” or the 2005 denuclearization agreement after six-party-talks, have ultimately broken down. Observers say North Korea has proved to be an untrustworthy negotiating partner.

“Two words: Dad's Playbook,” tweeted Jung H. Pak, a former Korea analyst at the CIA who is at the Brookings Institution, referring to previously failed negotiations with Kim Jong Il, the former leader of North Korea and the father of Kim Jong Un.

Any new talks would have to learn from these mistakes. The Heritage Foundation's Bruce Klingner, another former CIA analyst, said that past negotiations had “foundered on an overeagerness to achieve an agreement without insufficient focus on the details.” In particular, Klingner said, negotiations had led to short, vague texts that allowed “both sides to claim differing interpretations as to what was agreed upon” and were “marred by insufficient verification measures.”

Complicating this will be the apparent divisions between the Trump administration and Moon's government, with the South Korean leader having made a dramatic post-Winter Olympics bid for peace. Even in South Korea, though, there are deep divisions on talks with the North. “Some skeptics and critics wonder if the Moon administration will 'sell its soul' to Pyongyang and some even worry that the peninsula might be reunified under North Korean terms and rule,” Duyeon Kim said.

It may be possible for a good negotiating team to manage these difficulties, but the United States may be at a disadvantage here. Joseph Yun, the State Department's top expert on North Korea, recently announced his retirement, and the Trump administration has not nominated an ambassador to South Korea.

Alexandra Bell, senior policy director at the Center for Arms Control and Nonproliferation and an Obama-era State Department arms-control expert, said building a team to reach a deal with North Korea should be a priority for the Trump administration. “The president has often bragged about negotiating skills and about the fact that he thinks his administration is capable of great things,” Bell said. “Well, here's an opportunity for a great thing.

“North Korea is not a friend and has not proven to be a good partner in the past,” Bell added. However, “you don't get to negotiate these kind of things with your friends.”

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