COMMENT KCNA VIA REUTERS KCNA

North Korean leader Kim Jong-un watches the launch of a ballistic missile. The country flew the same type of missile over Hokkaido, Japan, in September 2017. Unblock the path to peace in North Korea Researchers must improve ways of verifying nuclear disarmament and collaborate on nuclear power, argues R. Scott Kemp.

here’s a lesson to take from the speed sceptical that diplomacy alone will deliver have been unfolding inside North Korea with which the US–North Korean a lasting solution. All previous attempts for the past six years suggest that now is the dialogue has oscillated between to work with North Korea have floun- time to begin a measured engagement (see Tthinly veiled threats of nuclear annihilation dered because of deep-rooted mistrust and ‘Reasons for optimism’). and the promise of cooperation: that con- reticent compliance from all sides. The same This is not to say that the world should structive dialogue between nations is never could happen again, especially if expecta- expect steady progress. The Iran nuclear more than a political decision away. Open- tions grow too quickly. But there are also agreement, by comparison, took 13 years ings can come quickly; when they do, it pays solid reasons for optimism. The motiva- to bring about. I was one of the scientists to be prepared. tions of all parties to stay the course are working to make that happen, and I watched Unfortunately, there are major technical higher than ever: North Korea is on the first-hand as planners experienced setback gaps in the ability of science to verify the verge of producing a significant nuclear after setback. Similarly, during the cold war, eventual nuclear disarmament of North arsenal, making the consequences of fail- arms control between the United States Korea. Closing these gaps will be crucial ure extremely high. On the positive side, and Soviet Union was achieved through to moving from the generalities produced the benefits of successful diplomacy could punctuated evolution rather than through for the global stage to specifics on the bring economic gains for both sides. North a single grand agreement. ground. Given that solutions will take time Korea holds an estimated US$10 trillion in In several ways, the former Soviet Union to develop, scientists and engineers need to untapped mineral reserves, including what might be a better model for understanding focus on these challenges — and soon. might be the world’s largest single deposit of North Korea than, say, Libya or Iran. North Understandably, many experts remain rare-earth metals. Structural changes that Korea can use its missiles and nuclear

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weapons for leverage; it is motivated discrepancies still cropped up1. The world Third, the international community does by a complex mix of economic distress ultimately accepted South Africa as being not know how much uranium or plutonium and security fears; and it holds an almost free from nuclear weapons for political, was consumed in North Korea’s weapons pathological distrust of the United States. rather than technical, reasons. North Korea tests. Weapon designs can use a wide range Thus, as with the Soviet Union, the world will be a very different case. of quantities, and only a small fraction is should expect North Korea to hedge its destroyed during the explosion. As such, bets, engage in brinkmanship and cheat on KNOWN UNKNOWNS on the basis of the explosive yield, it is not its agreements. An enlightened approach At present, at least three challenges would possible to estimate how much uranium or can nevertheless be resilient. For example, impede successful verification2. plutonium fuel was removed from stock- the United States stood by the 1972 Anti- First, there is no known way of detect- piles. North Korea could claim that large Ballistic Missile Treaty in 1985 when the ing secret centrifuge facilities for enrich- quantities of uranium or plutonium were administration of then US President Ron- ing uranium. These can be smaller than used to build its early weapons, while actu- ald Reagan learnt that the Soviet Union had an office building, would easily fit into an ally holding significant amounts in reserve. built prohibited radars. Instead of tearing up underground tunnel, consume very little In the absence of technical tools, inspec- the treaty, Reagan used the evidence to pres- electricity and release almost no thermal or tors will try their best using interviews, log- sure the Soviets into accepting a subsequent chemical emissions — all of which makes books and other records — but these could agreement that placed more restrictions on them hard to find. Based on the speed with easily be incomplete or forged. Robust tech- their arsenal. which North Korea built the one enrich- nical methods would provide an extremely One crucial difference is that denucleari- ment facility it has made public, there is valuable layer of confidence that does not zation — total nuclear disarmament and good reason to believe that it operates rely as heavily on trust. the removal of supporting nuclear facili- at least one other research facility. It has ties — was never on the table with the Soviet probably built other full-size production SCIENCE PRIORITIES Union as it is with North Korea. As a conse- facilities, too. These facilities need to be Solutions to these long-standing challenges quence, many of the verification challenges found and dismantled. lie at the frontiers of research. For example, associated with denuclearization were never Second, there is currently no way of if chemists or materials scientists could solved. estimating how much weapons-grade develop a way to sense uranium–fluorine South Africa is the only case in history uranium North Korea has produced. bonds in aerosols at levels between parts that comes close: it gave up its nuclear A forensic method is needed to reconstruct per billion and parts per trillion, this could weapons voluntarily in 1991 before the the production history for each of the pave the way for exposing clandestine apartheid-era National Party ceded power uranium-enrichment facilities that might uranium-enrichment plants. Detecting to the African National Congress. The out- be discovered. This process will help to uranium or fluorine alone would not work, going government did not want to bequeath confirm the completeness of declarations because both are relatively abundant, but nuclear weapons to its successors. The new and ensure that North Korea is not keep- the uranium–fluorine bond is unique to government cooperated by giving interna- ing a secret cache of enriched uranium for nuclear programmes. tional inspectors access to sites. Technical future use. Analytical methods might also be developed to check declarations about the past production of enriched uranium. REASONS FOR OPTIMISM There are ways to examine chemical resi- dues in facilities. None are reliable enough, Kim elevates the economy over military might because they are sensitive to operating conditions, such as humidity, that can vary There is growing evidence that North a policy enshrining scientific research widely from plant to plant and over time. Korea is undergoing a real shift. Its leader, and technological innovation, not military Methods that do not rely on chemistry, or Kim Jong-un, stepped into his father’s discipline, as the motive force for national that can combine multiple lines of informa- shoes 6.5 years ago, at age 28. He began progress. This April, Kim announced tion to control for variations, might help to his reign with displays of power, purging that his transitional byungjin policy had solve this challenge. internal challengers and fast-tracking the been fulfilled; the new party line is now to The third problem of estimating the development of nuclear weapons and devote all available resources to economic amount of material used in past weapon long-range missiles. It was a discouraging development. tests might be conquered by geochemists, start, but after cementing his authority over On the ground, there is evidence of a new hydrologists and petroleum engineers. They a sceptical military, he began to plant seeds urban-services economy. The number of could drill into the mountain where North of change. official shops in North Korea where ordinary Korea performed its tests, and assess the In March 2013, Kim unveiled a new citizens can buy basic goods has nearly amount of plutonium or uranium associated party line, byungjin — referring to ‘parallel doubled since 2010. Markets are now more with each detonation. Given the disturbed development’ of the economy and nuclear formally organized, with merchants renting rock zones, the oxidizing environment and weapons. Although the basis of the policy stalls from the government. Several private water transport of isotopes through the is not peaceful, it was nonetheless a taxi companies now compete for business mountain, this presents a challenging, long- liberalizing segue from songun, the ‘military in Pyongyang. And the government is term study. first’ policy of his father. He elevated his developing tourism sites in areas of The verification requirements out- economic advisers to the front of his unspoiled beauty to welcome outsiders and lined here are well suited to government retinue, where military officials used to their cash. laboratories, but history suggests that stand. He has also elevated the party in The Western-educated North Korean university and industry scientists can terms of its relationship to the military. leader might understand that his success play a valuable part in forging interna- At the 7th Congress of the Workers’ at home, and the survival of his nation, tional agreements as well. For example, Party of Korea in May 2016 — the first depends on finding a controlled way to in 1988, a group of non-government sci- such congress in 36 years — he adopted engage the outside world. R.S.K. entists from both the United States and the Soviet Union shored up confidence

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COMMENT UNCREDITED/AP/REX/SHUTTERSTOCK

Journalists from outside North Korea record the destruction of part of the country’s nuclear test site at Punggye-ri.

in the proposed Comprehensive Test Ban violations … even if it fails to detect a The full closure of North Korea’s nuclear- Treaty by demonstrating that even small, violation right away.”4 The United States weapons programme will take many years conventional explosions could be detected commissioned the JASON group of science of political horse-trading, inspections and at a Soviet nuclear test site, using seismic advisers to do a similar study5. It concluded verification work. There will be periods of monitoring. In 1991, physicist Thomas “verification will of necessity be less than optimism and of tension. When the poli- Neff, then at the Massachusetts Institute perfect … it must rely on difficult political/ tics do align, government advisers will be of Technology in Cambridge, proposed strategic judgments, as well as technical scrambling for solutions to the hard techni- turning the uranium from Soviet nuclear ones.” In short, trust comes as much from cal problems that impede progress. In antic- weapons into fuel for civil nuclear reactors. the people involved and the relationships ipation of those moments, researchers who For almost 20 years, starting in 1995, about they forge as it does from the data. wish to unblock the path to peace should 10% of US electricity was generated from There are opportunities to begin build- begin working now. ■ dismantled Soviet warheads. ing useful relation- Academics are often more able than ships now. One “Engaging with R. Scott Kemp is associate professor of government scientists to propose novel way is to use civil North Korean nuclear science and engineering at the ideas. They can proceed independently of nuclear energy as scientists and Massachusetts Institute of Technology political posturing, and they can communi- a bridge to more- engineers will (MIT), and director of the MIT cate to the public or to key decision-makers sensitive nuclear Laboratory for Nuclear Security and 3 itself build without layers of political filtering . issues, because confidence.” Policy in Cambridge. In 2010 and 2011, he Verification will be slow (as will it involves many served as science adviser in the US State diplomacy). It is unlikely that we will be able of the same technologies, experts and Department’s Office of the Special Advisor to achieve high confidence in the accuracy facilities. Earlier this year, North Korea for Nonproliferation and Arms Control. and completeness of North Korean declara- completed major construction on what it e-mail: [email protected] tions in the next decade. calls an experimental light-water power 1. von Baeckmann, A., Dillon, G. & Perricos, D. IAEA In the meantime, engaging with North reactor, at Yongbyon. However, the coun- Bull. 37-1, 42–48 (1995). Korean scientists and engineers will itself try does not have the capability to test fuel 2. Kemp, R. S. Ann. Rev. Earth Planet. Sci. 44, 17–35 build confidence. During the cold war, the for the reactor to international safety stand- (2016). Academy of Sciences of the USSR under- ards. South Korea has both the test facili- 3. Von Hippel, F. Citizen Scientist (American Institute of Physics, 1991). took a study of how it could ever trust the ties and the decades of experience needed. 4. Vasiliev, A., Gerasev, S. & Oznobischev, O. Sea- exceptionally adroit United States. The Cooperation between the two nations in Launched Cruise Missiles: Verification Solutions study concluded, “The criterion [for] a this area would help to establish trust, and (Institute for US and Canadian Studies, 1988). 5. Drell, S. et al. Verification of Dismantlement verification regime is the reduction to a would reduce the risk of an accident that of Nuclear Warheads and Controls on Nuclear minimum of pretexts for mutual suspicion could shower the citizens of South Korea Materials (JASON, The MITRE Corporation, about possible and significant concealed with radioactive fallout. 1993).

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