The North Korean Nuclear Threat Is Getting Worse By the Day

North Korea’s nuclear-weapons capabilities are increasing at an alarming rate. Presidents Donald Trump and Xi Jinping need to do something about it now.

This undated picture released by North Korea's Korean Central News Agency (KCNA) via KNS on March 7, 2017 shows North Korean leader Kim Jong-Un waving to North Korean officers during the launch of four ballistic missiles by Korean People's Army (KPA) during a military drill at an undisclosed location in North Korea.
Nuclear-armed North Korea launched four ballistic missiles on March 6 in another challenge to President Donald Trump, with three landing provocatively close to America's ally Japan. / AFP PHOTO / KCNA VIA KNS / STR / South Korea OUT / REPUBLIC OF KOREA OUT   ---EDITORS NOTE--- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO/KCNA VIA KNS" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS
THIS PICTURE WAS MADE AVAILABLE BY A THIRD PARTY. AFP CAN NOT INDEPENDENTLY VERIFY THE AUTHENTICITY, LOCATION, DATE AND CONTENT OF THIS IMAGE. THIS PHOTO IS DISTRIBUTED EXACTLY AS RECEIVED BY AFP.  /         (Photo credit should read STR/AFP/Getty Images)
This undated picture released by North Korea's Korean Central News Agency (KCNA) via KNS on March 7, 2017 shows North Korean leader Kim Jong-Un waving to North Korean officers during the launch of four ballistic missiles by Korean People's Army (KPA) during a military drill at an undisclosed location in North Korea. Nuclear-armed North Korea launched four ballistic missiles on March 6 in another challenge to President Donald Trump, with three landing provocatively close to America's ally Japan. / AFP PHOTO / KCNA VIA KNS / STR / South Korea OUT / REPUBLIC OF KOREA OUT ---EDITORS NOTE--- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO/KCNA VIA KNS" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS THIS PICTURE WAS MADE AVAILABLE BY A THIRD PARTY. AFP CAN NOT INDEPENDENTLY VERIFY THE AUTHENTICITY, LOCATION, DATE AND CONTENT OF THIS IMAGE. THIS PHOTO IS DISTRIBUTED EXACTLY AS RECEIVED BY AFP. / (Photo credit should read STR/AFP/Getty Images)
This undated picture released by North Korea's Korean Central News Agency (KCNA) via KNS on March 7, 2017 shows North Korean leader Kim Jong-Un waving to North Korean officers during the launch of four ballistic missiles by Korean People's Army (KPA) during a military drill at an undisclosed location in North Korea. Nuclear-armed North Korea launched four ballistic missiles on March 6 in another challenge to President Donald Trump, with three landing provocatively close to America's ally Japan. / AFP PHOTO / KCNA VIA KNS / STR / South Korea OUT / REPUBLIC OF KOREA OUT ---EDITORS NOTE--- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO/KCNA VIA KNS" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS THIS PICTURE WAS MADE AVAILABLE BY A THIRD PARTY. AFP CAN NOT INDEPENDENTLY VERIFY THE AUTHENTICITY, LOCATION, DATE AND CONTENT OF THIS IMAGE. THIS PHOTO IS DISTRIBUTED EXACTLY AS RECEIVED BY AFP. / (Photo credit should read STR/AFP/Getty Images)

The threat posed by North Korea’s nuclear-weapons program is getting worse — much worse. President Donald Trump and Chinese President Xi Jinping, meeting Thursday and Friday at Trump’s Mar-a-Lago resort in Florida, face an urgent and growing problem that is more severe today than ever before.

The threat posed by North Korea’s nuclear-weapons program is getting worse — much worse. President Donald Trump and Chinese President Xi Jinping, meeting Thursday and Friday at Trump’s Mar-a-Lago resort in Florida, face an urgent and growing problem that is more severe today than ever before.

Through 2015, Pyongyang likely had enough fissile material for only a small number of weapons, probably fewer than 20, which constrained North Korea’s nuclear options. North Korea, however, is busy increasing both its stocks of weapons-grade material and its capacity to make more.

Last month, International Atomic Energy Agency Director General Yukiya Amano reported that North Korea had doubled the size of its Yongbyon uranium enrichment plant. The Institute for Science and International Security credibly estimates that the North’s known uranium enrichment and plutonium production facilities are capable of producing enough material for four to six weapons in 18 months, and that if Pyongyang operates a second, covert uranium enrichment facility (as many analysts believe they will), the production capacity could be 50 percent higher.

Any estimate of North Korea’s nuclear capabilities is subject to considerable uncertainty because of the regime’s extreme secrecy and isolation. It nonetheless appears that under a worst-case scenario, and if left unchecked, North Korea’s arsenal could approach 100 nuclear weapons by 2024; even if those fears are not realized, the arsenal would be substantially larger than it is today. This would change the nature of the North’s nuclear-weapons threat along five dimensions.

First, North Korea would likely alter the deployment, doctrine, and posture of its nuclear force. Today, with a small arsenal, nuclear weapons are likely a last-ditch defense, without a sophisticated doctrine. With a more sizable arsenal, we can expect that the North would develop its doctrine, adopt a more aggressive posture, and even potentially pursue day-to-day deployments of nuclear weapons on alert. This would materially increase the threat of nuclear war on the Korean Peninsula. Moreover, Pyongyang might see a larger nuclear-weapons capability as cover to conduct more destabilizing conventional or terrorist attacks, such as the ROKS Cheonan sinking and Yeonpyeong island shelling, or more bombings and assassinations. This dynamic has already occurred elsewhere.

Second, larger stocks of fissile material will facilitate advances in North Korean weapons and delivery system capabilities. Each nuclear test consumes a weapon from the North’s arsenal, but as fissile material stocks grow, the relative cost in military capability becomes less important. Hence, the North is accelerating its nuclear testing, conducting two tests last year, while previous detonations were separated by about three years. More testing will enable the North to pursue smaller, lighter, and more powerful weapons designs, which in turn will increase the range of its ballistic missiles. Recent reports of a North Korean capability to produce lithium-6 are another indication of Pyongyang’s progress toward more advanced nuclear weapons.

Third, a more abundant supply of fissile material increases the risk of nuclear sales. North Korea has sold a wide range of dangerous things to dangerous people, including missiles to Libya and a plutonium production reactor to Syria. As with testing, the constraint of relatively small fissile material stocks makes sale of such material or a weapon relatively costly in terms of military capability. With a larger arsenal, that concern is eased. Moreover, if Pyongyang is facing tighter sanctions, the temptation to sell valuable nuclear weapons or materials may grow.

Fourth, if the North uses its increased arsenal to pursue day-to-day deployment of nuclear weapons on alert, the risk of accidental or unauthorized launch will increase. It is difficult to quantify this risk. Such an event has never occurred, despite decades of deployments by a handful of countries, but the North has little experience with this problem, and the risk would undoubtedly be higher than it is today.

Fifth, the risk of nuclear theft will become more acute. As fissile material production grows, and especially as more of it is handled in bulk processing facilities — where it is most vulnerable to gradual theft over time — opportunities for diversion will grow. North Korea is the most vicious police state on earth, but it is also deeply corrupt, coming in 174 out of 176 countries ranked by Transparency International. North Korean leader Kim Jong Un just fired his security chief for corruption. Moreover, as with the Soviet Union, the security apparatus might not survive political instability.

For decades we have lived with a relatively small North Korean nuclear threat. The United States and its allies tried policies ranging from bribes to coercion, but under China’s aegis, the North has flouted international law with impunity. As Pyongyang’s fissile material stocks grow, the urgency and nature of the threat is changing. Patience, strategic or otherwise, is no longer a viable option for Presidents Trump and Xi.

Photo credit: North Korea’s Korean Central News Agency (KCNA) via KNS/AFP/Getty Images

William Tobey is a senior fellow at Harvard Kennedy School's Belfer Center for Science and International Affairs was most recently deputy administrator for defense nuclear nonproliferation at the National Nuclear Security Administration.

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