Why would North Korea choose to use VX, a banned nerve agent, to assassinate Kim Jong-nam? Here, Emily Werk puts this provocative operation into context, suggesting that the weapon has two important attributes: its highly lethal nature and a fearsome reputation.

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By Emily Werk, Special Assistant to IISS–Americas Executive Director Mark Fitzpatrick

North Korea is certainly living up to its reputation for macabre provocations. On 13 February, the country reportedly used the banned VX nerve agent to assassinate Kim Jong-nam, the half-brother of Kim Jong-un. The assassination in Malaysia’s Kuala Lumpur International Airport was a public and provocative operation confirming that North Korea has an active chemical-weapons programme. The country is not a signatory of the Chemical Weapons Convention, one of only four holdouts to the almost universal treaty.

As reported in the IISS Strategic Dossier North Korean Security Challenges: A net assessment, the country is presumed to have between 2,500 and 5,000 tonnes of chemical agents. At the time of the dossier’s publication in 2011, experts did not believe that North Korea was actively expanding or improving its chemical-weapons arsenal. However, assessments indicate that North Korea’s three chemical-weapons plants could produce up to 12,000 tonnes of chemical weapon agents a year.

VX is a horrible weapon, whether used on the battlefield or as tool of assassination. Like all nerve agents it disrupts the normal function of enzymes at muscle and gland junctions, causing victims’ muscles to be continuously stimulated. They are unable to relax these clenched muscles, making it impossible to breathe normally. The high concentration of the dose Kim was attacked with meant he succumbed to respiratory failure within minutes, dying on the way to hospital.

Fearsome reputation may explain use of nerve agent

The Chemical Weapons Convention classifies VX as a Schedule 1 chemical, indicating it poses a ‘high risk to the object and purpose of this Convention by virtue of its high potential use in activities prohibited’. Unlike some lethal substances, Schedule 1 chemicals have little or no civilian use. North Korean officials were surely aware of VX’s condemned status. So why would Pyongyang choose to kill Kim Jong-nam with VX rather than a conventional weapon, or a less identifiable chemical toxin?

There are two potential reasons for North Korea to choose VX: the weapon’s lethality, which almost guaranteed tactical success, and its fearsome reputation. VX is nearly always lethal when given in high doses to an unprotected victim. Chemical weapons are also intimidating to enemies. In Syria, for example, experts have suggested that the Bashar al-Assad regime deliberately chose to conduct chemical attacks rather than conventional assaults because of the former’s frightening effect. Kim Jong-un is no stranger to such acts of intimidation; he reportedly ordered the assassination of his defence chief by anti-aircraft guns.

In the event of escalation on the Korean Peninsula, North Korea could seek to deter attack by threatening civilian populations with chemical warfare. They would be particularly vulnerable to a chemical attack because they lack proper protective gear and are untrained in identifying and addressing symptoms. In the event of a widespread attack, medical professionals would likely be unable to administer the necessary therapy in time. There is also no medical consensus on which antidotes to use for nerve agent poisonings, and no universally agreed dosing instructions.  

How effective are battlefield chemical attacks?

North Korea might also seek to use chemical weapons against US and South Korean forces, but chemical warfare is often tactically unsuccessful. It was first used during the First World War, but proved effective only in specific scenarios where unprotected enemy soldiers were ‘sitting ducks, massed together in low-lying trenches, static targets for weeks or months at a time’. In fact, the first time that the British Army deployed chlorine gas, it drifted back over British troops when the wind direction shifted. The official British history of the First World War One noted that, on the whole, ‘gas achieved but local success, nothing decisive; it made war uncomfortable, to no purpose’.

In twenty-first century warfare infantries are highly mobile, with proper anti-gas equipment and chemical-weapons training. These developments would make it more difficult for North Korea to successfully deploy chemical weapons on the battlefield. As one expert explains, ideal weather conditions are also necessary to preserve the potency of the chemical. Delivering the substance is an additional challenge; the conventional explosives in artillery or rockets can destroy much of the material.

Without a sound tactical purpose, North Korea may see its chemical weapons mainly as a deterrent: like nuclear weapons, they are weapons of mass destruction and panic. But while North Korea boasts of its alleged nuclear capabilities, it does not acknowledge its chemical-weapons programme. In light of this fact, and the limitations of chemical weapons, it may be easier to persuade the country to give up its chemical warfare stockpiles than its nuclear arsenal. Verification would be difficult, however.

Pyongyang’s angry rejection of Malaysia’s conclusion that Kim Jong-nam was assassinated using VX agent may indicate how North Korea would react to any challenging findings by the Organisation for the Prohibition of Chemical Weapons (OPCW). Still, it was notable that a North Korean diplomat in Malaysia asked the government there to send samples of the substance found on the body to the OPCW for verification. This presents an opportunity to press North Korea and potentially cut the risk of full-blown chemical attacks. 

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