Over the past few weeks several press reports have suggested that the Islamic State of Iraq and the Levant (ISIL) have resorted to chlorine use in attacks in Iraq and Syria.
The grouping is no stranger to chlorine. In some earlier incarnation it was known as al Qaeda in Iraq (AQI) and later it rebranded itself as the Islamic State of Iraq when it explicitly began trying to control territory. Harsh imposition of its strict interpretation of Sharia law and extreme violence towards anybody refusing total subjugation to its rule soon had Sunni tribal leaders uniting in resistance early in 2007. They also began cooperation with forces of the US-led coalition occupying Iraq since 2003 and the Shia-dominated Iraqi government. AQI started mounting large-scale operations involving several hundreds of fighters to capture local seats of power. During the first half of 2007 suicide attacks with lorries rigged with a large quantity of explosives evolved from isolated incidents to terrorise and destabilise societies to a tool integrated in assaults against government centres and fortified positions. After an isolated attempt in October 2006, AQI launched almost 20 chlorine attacks in the first half of 2007.
This posting is a first effort to understand the dynamic behind ISIL resorting to chlorine and perhaps some other toxic chemical substances in military operations in Iraq and Syria. If current chlorine attacks can be confirmed, then some interesting parallels with the brief episode in Iraq may be discerned (but the hypotheses do require further study to be confirmed):