August 17, 2015

TSG IntelBrief: The Islamic State’s Weapons of Mass Destruction

• There have been recent reports of three attacks by the Islamic State in northern Iraq with the possible use of mustard gas—though chlorine is the more likely substance

• Like the Assad regime in Syria, the Islamic State has used chlorine in mortar and rocket attacks, as well as in car bombs; the gas causes intense respiratory problems and burns victims’ skin and eyes

• If the Islamic State possessed mustard gas, other chemical weapons, or worse, it would certainly use them; there is no shortage of toxic chemicals in the territory the group controls

• While weapons of mass destruction such as chemical weapons generate publicity and concern, the group’s low-tech bombs and bullets remain the greatest threat to the region.


Reports that the so-called Islamic State may have used mustard gas in several recent attacks against Kurdish Peshmerga units in northern Iraq have generated concern that the group has acquired and used chemical weapons of mass destruction. There has been no verification that the irritant was mustard gas, and it is more probable that it was chlorine gas. This likelihood stems not just from the availability of chlorine (which has vital civilian uses such as water treatment) but from the fact that the Islamic State has a long history of chlorine attacks.

As early as October 2006, when the group had just reorganized as the Islamic State of Iraq (ISI), it used chlorine in massive truck bombs. From October 2006 to June 2007, the group conducted 15 bombings involving chlorine gas. No deaths were directly attributed to chlorine exposure (approximately one hundred people died from the series of attacks), but many civilians and soldiers were hospitalized or treated for chlorine-related symptoms. The bombings ranged from car bombs that contained chlorine tanks to massive tanker trucks filled with the gas. Fortunately, chlorine is not very effective when used in car bombs, and tends to burn up in the heat and not disperse widely.

The reason the group uses chlorine is less for its impact on the battlefield (if one can view markets and neighborhoods as battlefields) than for its impact on the psyche. The Islamic State is driven by terror and there are few things more terrorizing to a population than the specter of chemical weapons. War-torn societies experience higher levels of terror when word is passed that chemical weapons are being used, even if they are out of the immediate danger zone. The indiscriminate and uncontrollable nature of poison gas renders no one safe—which indeed is often the case, even without the gas. Chemical weapons bring daily horror into more vivid light.

This is also one reason why the Assad regime in Syria has repeatedly used chlorine bombs against civilians. Unfortunately, the Syrian air force's method of delivery is far more effective and injurious than anything the Islamic State can attempt; both barrel bombs and rockets spread chlorine over densely populated city blocks and neighborhoods. After agreeing to give up its chemical weapons in 2013, the Assad regime turned to chlorine as an alternative since it is not included in the list of banned substances, given its many positive uses. Despite increased international attention, the Assad regime continues to use chlorine barrel bombs to devastating effect.

The Islamic State might not possess mustard gas, but it certainly would use such a weapon if it did. This remote possibility increases the longer the Islamic State controls large swaths of land in Syria and Iraq. Especially in Syria, where the group occasionally takes over government-held locations, there is a chance that some banned materials are present. Likewise in Iraq, the country is littered with ammunition dumps and buried waste. It is therefore conceivable the group could get its hands on some rudimentary chemical weapons, which tend to decay and leak if not stored properly. That said, the far greater danger is in the more mundane means of death that the group possesses in great abundance: bullets and explosives.

While the image of a terrorist group armed with chemical weapons (whether chlorine gas or more lethal forms) makes for vivid imagery and reporting, it is improbable when compared to other threats. The far more lethal threat is the one the group demonstrates daily across two countries: well-armed fighters unafraid to die using massive truck bombs to soften a target for a ground assault with machine guns and rocket-propelled grenades. The group will seek any means of leverage over a population, and chemical weapons certainly provide that. Yet, the hard reality is that the group hardly needs such weapons to terrorize people.


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