After Malaysian police announced on Friday that Kim Jong Nam, half-brother of North Korea’s leader Kim Jong Un, had been killed with the deadly nerve agent VX, two main theories emerged for the assassins’ choice of weapon.
First, Kim’s sudden demise was perhaps supposed to look like a death from natural causes, but that plan was botched when the two women who were allegedly hired by North Korean agents to smear his face with VX were caught in the act on closed-circuit television.
The more chilling possibility is that Kim Jong Un decided to use the assassination to let his adversaries to know what they’ve long suspected: that North Korea possesses lethal nerve agents — and is prepared to use them.
That’s a worry for South Korea and the US military — especially because so little is known about Pyongyang’s chemical weapons. “It's very hard to make an accurate intelligence assessment,” Gregory Koblentz, who heads the biodefense graduate program at George Mason University in Virginia, told BuzzFeed News.
The big problem with monitoring for chemical and biological weapons is that they can be made in factories with legitimate peaceful uses.
North Korea normally goes out of its way to keep its adversaries guessing about its precise weapons of mass destruction (WMD) capabilities, but even the best-concealed nuclear test sends seismic waves ringing through the Earth that reveal a lot about the detonation. And when missiles are test-fired, their trajectories tell a story about their likely maximum range.
But if a state wants to produce nerve agents, it can do so using a factory that is outwardly indistinguishable from a plant making drugs or pesticides. That’s one reason why controversy still swirls around President Bill Clinton’s 1998 decision to launch a cruise missile attack on the al-Shifa pharmaceuticals plant in Sudan — alleged to have been used to make chemical weapons for al-Qaeda.
North Korea’s chemical industry steadily churns out materials including vinalon, a fiber widely used for textiles in the pariah nation even though it’s stiff and hard to dye. Those same factories have long been suspected of producing chemical weapons.
Without boots on the ground, however, it’s hard to know exactly what these plants are making. And North Korea is one of the few nations (along with Israel, Egypt, and South Sudan), not to have joined the international Chemical Weapons Convention — so it isn’t subject to international inspections.
It’s a similar story with biological weapons, where disease-causing microbes are turned into a deadly arsenal. The same biotechnology that can create vaccines or biopesticides can incubate bioweapons.
In June 2015, for example, Kim Jong Un posed for pictures at the Pyongyang Bio-technical Institute. The plant has large bioreactors to grow batches of Bacillus thuringiensis (Bt) bacteria, which can be used as a natural insecticide to protect crops from agricultural pests. But those same bioreactor vessels — which are not cheap — could also grow Bacillus anthracis, the bacterium that causes anthrax.
“Economically, it does not make sense for them to have a Bt facility,” Melissa Hanham, a senior research associate at the Center for Nonproliferation Studies in Monterey, California, told BuzzFeed News. “China would happily give them all the organic pesticides they want.”
Last week’s announcement that VX was used to kill Kim Jong Nam at Kuala Lumpur airport seems to confirm that North Korea possesses the most lethal nerve agent known to science — which paralyzes the diaphragm, causing death by asphyxiation.
But this isn’t the first time that VX has been used as an assassin’s weapon.
In 1994 and 1995, Masami Tsuchiya, a chemist with the Japanese cult Aum Shinrikyo, made small quantities of VX used in three attempted assassinations — one of which killed a suspected police informant.
Reports from Malaysia suggest the attack on Kim Jong Nam may have been more sophisticated, with each of his attackers carrying a cloth bearing a small amount of different chemicals that reacted together on his skin to form VX. US military scientists devised a similar formulation, mixing a relatively nontoxic substance called QL with sulfur to form VX.
Even if something similar was used to kill Kim Jong Nam, the big unknown is whether North Korea is able to deploy large quantities of a similar binary weapon in artillery shells or missile warheads that would mix the chemicals in flight, and then explode just before impact, spreading VX over a large area.
Experts assume that Pyongyang has stockpiles of both nerve and mustard agents — older weapons that blister the skin.
Reports from the South Korean defense ministry, published most recently in 2014, suggest that Pyongyang possesses between 2,500 and 5,000 tons of chemical weapons. But it’s unclear where those numbers come from, or exactly what chemicals it has stockpiled.
“The intelligence is poor,” Raymond Zilinskas, who heads the chemical and biological weapons program at the Center for Nonproliferation Studies, told BuzzFeed News.
Pyongyang is known to have collaborated on WMDs with Syria, which in 2013 agreed to destroy its stocks of nerve agents to avoid US military intervention in the nation’s civil war. The agreement came after a sarin attack near Damascus killed more than 1,000 civilians, and sparked global condemnation. North Korea previously supplied Syria with Scud missiles used to deliver chemical weapons, and in 2009 the Greek authorities detained a merchant ship carrying supplies from North Korea, destined for Syria, including 13,000 chemical protective suits.
Given that relationship, experts believe it’s prudent to assume that Pyongyang’s arsenal is similarly formidable to the one once held by Syria. This could include mustard agents, which blister the skin and damage the eyes, lungs, and internal organs.
“Most likely, the North Koreans would have nerve agents and maybe mustard in their stockpile,” Koblentz said.
If fighting did break out on the Korean peninsula, using chemical weapons may be one of the North’s best military options.
While Kim Jong Un is unpredictable, seasoned Korea watchers see method in what may sometimes seem like madness. And that leads them to doubt that he actually intends to use nuclear weapons — which make more sense as a bargaining chip in dealing with the US and other powers.
Pyongyang’s chemical arsenal is a different prospect, however. “If there’s a conflict on the Korean peninsula, North Korea would probably use chemical weapons early on,” Koblentz said.
US and South Korean military bases are an obvious target. Survivors would be forced to wear bulky chemical protection suits, and decontamination would be a nightmare, giving North Korean troops a fighting chance against a technologically superior force. And even the threat of a nerve gas attack on Seoul and other cities could create panic.
That’s why North Korea’s chemical weapons are a big concern for the US and its allies, even though they’d be much less devastating than a nuclear blast.
If Kim Jong Un used a nuclear weapon, he would be committing national suicide, given likely US retaliation. But if the Koreas ever resume hostilities, the disturbing reality is that chemical attacks from the North would make military sense.
Peter Aldhous is a Science Reporter for BuzzFeed News and is based in San Francisco. His secure PGP fingerprint is 225F B2AF 4B8E 6E3D B1EA 7F9A B96E BF7D 9CB2 9B16
Contact Peter Aldhous at email@example.com.
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