Use of mustard gas in the Syria conflict confirmed. Reuters.

Rebel fighters engaged with ISIS in the town of Marea. Reuters

Experts have determined that mustard gas was used in a battle between ISIS and another rebel group. Reuters. The Organization for the Prohibition of Chemical Weapons (OPCW) released a report that showed at least two people were exposed to the gas in the town of Marea, north of Aleppo. One of the victims, a baby, likely died from the attack. This is the first confirmed attack with mustard gas in the Syria conflict. Syria gave up their chemical weapons 18 months ago, so it is unclear where the weapons came from. Though the report did not say who was responsible for the attack but other sources have confirmed that it was ISIS that used the mustard gas. This is not the first time chemical weapons in the Syria conflict as both the regime and ISIS have been accused of using chlorine as a weapon. 

My Comment:

ISIS has really been stepping up their game when it comes to weapons of mass destruction. Though ISIS has been using chlorine as a weapon for quite some time now, this is the first time they have conclusively used mustard gas. Though chlorine is a terrible and dangerous weapon in its own right, mustard gas is at another level. In addition to causing deaths through suffocation, mustard gas causes terrible gas to any skin exposed as well as damaging the lungs if inhaled. The inclusion of this weapon on the battlefield in Syria is deeply disturbing.

The obvious question is where on earth did ISIS get mustard gas? The most obvious possibility is that ISIS simply captured weapons from the Syrian regime before they eliminated their chemical weapons. Syria had massive chemical weapon stockpiles, so it wouldn't be too surprising if ISIS had captured a cache or two. 

The other option is that ISIS is creating their own mustard gas. I talked before about how ISIS was creating their own chemical weapon delivery systems, such as mortar shells. Those attacks used chlorine which shows that they have at least a little expertise in producing chemical weapons. To be fair though, chlorine is a lot easier to work with then mustard gas. I'm not sure if ISIS has the ability to mass produce mustard gas. They do have the ability to make a delivery system though.

I've talked before about the psychological effects these weapons can have. If ISIS were to deploy these weapons on a mass scale it may turn the balance of the war to their favor. Very few factions in the Syria conflict have anything in the way of chemical warfare gear. Without protection, anyone who gets attacked by these weapons will take heavy casualties. 

There is also a good chance that anyone attacked by these weapons will abandoned their positions out of fear. This tactic seems to be a good match for ISIS's most effective tactic of using car bombs to destroy enemy lines and demoralize enemy troops. Indeed, terror seems to be ISIS's main weapon. From terrorist strikes, to chemical weapons to brutal executions, ISIS uses fear as more effective weapon then all their firearms combined. 

So how do you counter these weapons? The first step would be for all factions to gain chemical weapons gear to protect their troops from attacks. Chem suits and gas masks aren't fool proof but it does mean that people will have a chance when they are attacked. Second, any factories that are producing chemical weapons need to be a priority for US and/or Russian airstrikes. Other then ISIS's leadership I can't think of a more important target then destroying any chemical weapons production facilitates. Finally, anyone in ISIS that has knowledge or experience in making and deploying these weapons need to be captured or killed as soon as possible. 

The ultimate fear is that ISIS will use these weapons in a terrorist attack. Though ISIS rarely strikes outside of its own borders, it is possible that they could use these weapons outside of Iraq and Syria. Turkey could be a major target and Europe isn't outside the realm of possibility either. And even if ISIS is destroyed the people that have developed these weapons could export their knowledge to other terrorist organizations. The threat of a terrorist chemical weapons attack may outlast ISIS.