Dangerous Dealings: North Korea's Nuclear Capabilities and the Threat of Export to Iran
Hecker, Siegfried S., Liou, William, Arms Control Today
On Oct. 9, 2006, North Korea conducted a nuclear test and proclaimed itself a world nuclear power. The explosion yield was less than one kiloton, much less than the first nuclear test of other states and even less than the expected yield of four kilotons that North Korean officials forecast to their Chinese counterparts. Nonetheless, the test demonstrated Pyongyang's mastery of the nuclear fuel cycle and at least rudimentary nuclear-weapon design and manufacturing capabilities.
On Feb. 13, North Korea signed a six-party agreement to take initial actions to implement a Sept. 19, 2005 Joint Statement tor the eventual abandonment of its nuclear weapons program. While this is welcome news, the road to the abandonment of North Korean nuclear weapons and capabilities will be long and arduous, and success is far from guaranteed. Its nuclear program still poses significant risks to international security, the most serious of which is the export of nuclear materials, expertise or technologies to states such as Iran and the potential for subsequent proliferation to terrorists.
It was clear by 1994 when Pyongyang signed the Agreed Framework1 with the United States that North Korea had mastered the basic technologies required to produce and separate plutonium, which has subsequently formed the centerpiece of its nuclear weapons program. Experts have estimated that North Korea could have produced and separated nearly 10 kilograms of weapons-grade plutonium by then, although they have acknowledged very large uncertainties in that estimate.2 Moreover, the 8,000 spent fuel rods that were then stored in a spent fuel pool contained roughly an additional 25 kilograms of plutonium.
The Agreed Framework froze all but maintenance activities at North Korea's Yongbyon nuclear complex from 1994 to the end of 2002. In December 2002, following a political altercation with the United States over accusations of conducting a covert uraniumenrichnient program and subsequent suspension of U.S. heavy fuel oil shipments, North Korea expelled International Atomic Energy Agency (IAEA) inspectors. In January 2003. it announced its withdrawal from the nuclear Nonprolireration Treaty and restarted its five-megawatt (electric capacity) nuclear reactor to strengthen its "deterrent" by reprocessing plutonium from the spent fuel stored since 1994.
Since the demise of the Agreed Framework, it has been difficult to assess developments in North Korea's nuclear program. International access to Yongbyon, which reportedly employs about 3,000 scientists, engineers, and research personnel alone,3 has been essentially terminated. However, one of the authors (Hecker) had the opportunity to visit Yongbyon in January 2004 and held additional discussions with its technical leadership in Pyongyang in August 2005 and November 2006.4 This assessment of North Korea's technical capabilities is based on open literature augmented by what was learned during these visits.
Nuclear Fuel-Cycle Capabilities
North Korea's nuclear program began with a 1959 nuclear cooperation agreement with the Soviet Union. That pact led to the construction of the nuclear research facilities at Yongbyon, the training of North Korean scientists and engineers, and geological surveys that ultimately discovered large deposits of uranium ore and graphite in North Korea.' Although the Soviets did not intend for this help to assist Pyongyang's development of nuclear weapons, it allowed North Korea to master the plutonium fuel cycle.
In the 1960s, the Soviet Union supplied North Korea with its first reactor, a small IRT-2000 research reactor fueled by highly enriched uranium (HEU), along with a small hot-cell facility for isotope production. Today, this reactor is used sparingly for medical isotope production because Pyongyang has not been able to acquire fresh fuel since the demise of the Soviet Union.
By 1980, North Korea had launched an ambitious program of reactor construction to build a national nuclear power industry. …