Pyongyang’s Radioactive Fingerprints: Nuclear Forensics In Action
On Feb. 12, 2013, several thousand feet beneath the rugged mountains of the Korean Peninsula, a massive blast rocked the earth, sending both real and figurative shockwaves through the international community. That morning, in monitoring stations scattered across the globe, geologists registered the detonation as unusual seismic activity, which appeared to emanate from Hamgyong — North Korea’s northernmost province.
Far from the epicenter, analysts dependent on the International Monitoring System — a network of seismic, hydroacoustic, infrasound and radionuclide sensors established under the Comprehensive Nuclear Test Ban Treaty Organization — leaned into their screens, scrutinizing data with a mix of urgency and apprehension. Days turned into weeks as the world awaited confirmation of what many had already surmised.
Two months later, the Vienna-based CTBTO made a pivotal announcement. Their radionuclide station in Takasaki, Japan — some 620 miles from the suspected test site — detected elevated levels of xenon-131 and xenon-133, two radioactive isotopes synonymous with nuclear fission. Due to the depth of the blast, these noble gases emerged from the test site slowly, but their significance was indisputable. Combined with the seismic readings which suggested a 6-kiloton explosion, the gases not only confirmed a nuclear test, but also produced radioactive fingerprints specific to North Korean material and devices.
The February 2013 incident served as more than a confirmation of suspicions. It stood as a testament to the intricate web of technologies and expertise that comprises the field of nuclear forensics. Here, a diverse array of scientific disciplines converges to perform a singular task: to identify the type and origin of nuclear material used in a detonation and attribute it to a specific actor. In an era where the proliferation of nuclear weapons remains one of the gravest threats to global security, this capability is not just technical — it is strategic.
For the Defense Department, nuclear forensics is one of several capabilities nested in its broader deterrence strategy. And by maintaining a world-class nuclear forensics enterprise, the department sends a powerful message to potential adversaries: any nuclear activity, no matter how well concealed, is subject to detection and will be met with accountability.
Following the CTBTO’s announcement, Jon Wolfsthal, the director of global risk at the Federation of American Scientists, argued that the North Korean test offered a silver lining. The “detection of the … test shows [that the Nuclear –Test Ban Treaty] can be verified,” he said. In the wake of the 2013 detonation, the IMS’s performance “all but put to rest” concerns over underground test attribution. After all, if a blast site buried under 4,400 feet of igneous rock failed to conceal a critical mass experiment, what could?
Nothing Gold Can Stay: The Emerging Threat Environment
The world has shifted in ways that few could have anticipated a decade ago. Clear dichotomies that characterized the war on terror have given way to a complex international landscape, where old adversaries resurface with renewed vigor, and new powers rise with unprecedented speed. A decade ago, the 2010 Nuclear Posture Review described a threat environment characterized by unprecedented cooperation. It spoke of Russia and the United States no longer as adversaries but as partners in preventing nuclear terrorism and proliferation by non-state actors like al-Qaeda.
Today, that cautious optimism has all but evaporated. The Defense Department’s focus has shifted sharply toward state-based threats, as evidenced by the 2022 Nuclear Posture Review, which identifies China’s rapid military modernization and Russia’s aggressive behavior as central concerns. “The People’s Republic of China remains our most consequential strategic competitor for the coming decades,” it asserts, while simultaneously condemning Russia’s “unprovoked, unjust and reckless invasion of Ukraine.”
This evolution reflects a reality where the United States faces not just one but multiple nuclear-capable — and seemingly aligned — adversaries. The contemporary threat environment is troubling, as China grows the size and scope of its nuclear arsenal, abandoning a minimal deterrent posture to gain strategic advantages over the United States. Concurrently, as Russia struggles to achieve a favorable outcome in Ukraine, it finds practical reasons to trade its mature nuclear technology and expertise for conventional munitions and manpower.
The alliance between these two powers — and belligerent nations like North Korea and Iran — is more than a diplomatic formality; it’s a strategic convergence that poses real challenges. Last week, Drew Walter, Deputy Assistant Secretary of Defense for Nuclear Matters, expanded on the emerging dynamic. “You can see it in the press and in the statements of leaders in Russia and China and North Korea,” he said. “The treaties of everlasting friendship between these countries, [and] cooperation … between North Korea and Russia — where the former sends troops to fight on the latter’s behalf — are unprecedented.”
Russia’s protracted occupation of Ukraine produced unanticipated consequences. Pyongyang undoubtedly sees an opportunity to expand its nuclear arsenal by contributing bodies and bullets to its longtime ally. Last month, Secretary of Defense Lloyd J. Austin III confirmed the presence of North Korean troops in Russia, expressing concern over their involvement in the conflict. “If their intention is to participate in this war on Russia’s behalf, that is a very, very serious issue,” he said.
Iran, too, enters the equation by trading weapons — like its Shahad “kamikaze” drones — for favorable treatment from an established nuclear power. Earlier this month, Pentagon Press Secretary Air Force Brig. Gen. Pat Ryder highlighted the “continued collusion” between Russia and Iran. The fact that Russia accepts munitions from an international pariah like Iran underscores the lengths to which each nation will go to bolster their positions.
Today’s threat environment is further complicated by the erosion of longstanding nuclear taboos. The once unthinkable use of nuclear weapons is no longer beyond contemplation for some state actors. In February 2022, following its invasion of Ukraine, Russia recklessly brandished its nuclear arsenal, threatening escalation to deter and dissuade support for its overmatched neighbor.
North Korea’s 2013 nuclear detonation appears almost straightforward against the backdrop of the present. A decade ago, the challenge lay in detecting and attributing a single, isolated event — a task accomplished through the concerted efforts of monitoring systems and forensics professionals. Now, the landscape is markedly more complex, and America’s nuclear forensics competencies — which were largely honed during the Cold War — must quickly adapt to address it. In response, the Defense Department and Nuclear Matters convened their inaugural Nuclear Forensics Research and Development Innovation Workshop, held Nov. 13-15, at the National Defense University in Washington, D.C.
Gathering Minds at Fort McNair: The Nuclear Forensics Research and Development Innovation Workshop
During the workshop, some of the nation’s leading minds, representing 12 preeminent institutions — including the Lawrence Livermore National Laboratory, the Savannah River National Laboratory and the Johns Hopkins University Applied Physics Laboratory — filed through the steel door securing an executive conference space in National Defense University’s Marshall Hall. Dressed sharply in button-down shirts, ties, blazers and sport jackets, they settled into the room’s white leather armchairs, unholstered their notepads, pens and pencils, and prepared to tackle some of the critical challenges facing the Defense Department and Nuclear Matters.
The Nuclear Forensics Research and Development Innovation Workshop kicked off with a series of opening remarks and threat briefs. Drew Walter took the podium first, and the significance of his presence resonated with the room. Walter, who cut his teeth on the technical side of nuclear research at Sandia National Laboratories, is now charged with shaping the Defense Department’s strategic nuclear capabilities. He underscored the importance of the workshop as he welcomed his audience — whom he affectionately dubbed “fellow nerds.”
“We are no longer responding to the threats of yesterday,” he began. “Today’s adversaries are more capable, better coordinated and more emboldened, [and] the work you do here must reflect that urgency.”
Throughout his remarks, Walter emphasized the demand for “bigger projects” with far-reaching impact, urging participants to think boldly and challenge the conventional pace of innovation. “[What] you develop in this room will resonate beyond these walls,” he said, “deterring adversaries, strengthening alliances and shaping the decisions of world leaders.”
His speech framed the workshop as a rare opportunity to bridge the technical and policy domains, prompting attendees to define not only solutions but the very problems at the core of nuclear forensics. “If you define the problem correctly,” Walter said, quoting Steve Jobs, “you almost have the solution.” That sentiment hung in the air as the room turned its focus to a singular mission: reshaping nuclear forensics to meet the demands of a rapidly evolving security landscape.
The inaugural nuclear forensics workshop is unprecedented, not merely in its assembly of diverse expertise but in its mandate for immediacy and impact. The gathering was more than a meeting of minds; it was a strategic response to a world where nuclear threats are no longer theoretical but pressing realities. And Walter set the tone for the workshop, stressing extraordinary cooperation to address technical capability gaps before they emerge. “We are still using technology and infrastructure that was designed to respond to [challenges] that existed 70 years ago,” he said. “We must regain our sense of urgency and consider how we can outpace the threat.”
Walter’s message was unequivocal: the challenges of today demand solutions that are both bold and actionable. He highlighted the Department’s investment in — and commitment to — nuclear forensics as a means of deterrence. “Going forward, the Defense Department will prioritize funding to big projects that are innovative, with a clear path to implementation involving multilab and interdisciplinary collaboration,” he declared.
The workshop was designed to foster such collaboration. Attendees were encouraged to break free from traditional silos, engaging in interdisciplinary brainstorming sessions that paired physicists with policy analysts, and engineers with intelligence experts. And that diversity was intentional. “Your perspectives [are] vital to the outcome of this workshop,” Walter noted. “We know you are the right folks to do this work because you attempt to solve complex problems every day.”
Throughout the event, participants delved into critical challenge areas identified by the Defense Department, focusing on developing deliverable solutions. Walter asked the workshop’s attendees to help bridge their technical aptitude with Nuclear Matter’s policy objectives. “Nuclear deterrence depends on our ability to credibly communicate that we are able to identify those responsible for nuclear weapons use,” he said. “Our nuclear forensics science and technological capabilities discourage our adversaries from attempting to hide behind the fog of war.”
The workshop also sought to address obstacles impeding innovation, recognizing that the path from groundbreaking research to fielded capability is often fraught with challenges. Walter called for a candid assessment of these hurdles. “We recognize that your unique perspective can give us valuable insight on the challenges we haven’t anticipated,” he said. “Whether it’s the small administrative headaches that eat away at valuable time or larger roadblocks that hinder overall progress, any insight you provide us is valuable.”
The collaborative environment fostered not only creative solutions but also new connections across the nuclear forensics enterprise. By leveraging multilab teams and interdisciplinary expertise, the workshop accelerated the development of high-impact projects that could be rapidly deployed in the field. For three days, Walter and his team continuously urged attendees to “re-evaluate [their] roles” and “share [their] perspectives.”
The innovations conceived during these sessions have the potential to thwart adversaries by demonstrating the United States’ commitment to advancing its capabilities in the realm of nuclear detection and attribution. “We don’t typically innovate well inside the Beltway, and that’s why we need your bright minds from across the country,” Walter admitted. “What you accomplish here can mitigate threats even as the security landscape changes.” The deputy assistant secretary continued, encapsulating the workshop’s imperative and the broader strategic context. “Nuclear forensics is a message of deterrence, and we need deterrence, in all its forms, now more than ever,” he stated.
The workshop marked a decisive step forward in the effort to address evolving nuclear threats. It answered the 2022 National Defense Strategy’s call to abandon “business as usual,” by calling together leading minds to reimagine nuclear forensics for a rapidly changing world. By fostering interdisciplinary collaboration focused on deliverable solutions, it underscored the United States’ commitment to innovation as a cornerstone of security. Deputy Assistant Secretary Walter’s enthusiasm with the workshop’s potential resonated in his closing remarks. “Always bet on American innovation,” he said. “Together, we will create solutions that define the next era of deterrence and ensure the safety of billions of people around the globe.”
This Defense news article "Nuclear Forensics Workshop Convenes in D.C.; Collaborates, Innovates in the Name of Deterrence" was originally found on https://www.defense.gov/News/News-Stories/
