NUCLEAR, BIOLOGICAL AND CHEMICAL WEAPONS
August 5, 2015: ISIL (al Qaeda in Iraq and the Levant) is apparently trying to build chemical weapons ammunition by filling 120 mortar shells with potentially lethal industrial chemicals. The most common chemical used is chlorine, but some shells have also been found filled with a grain fumigant and there are plenty of other noxious chemicals in areas controlled by ISIL. Chemicals like this can be lethal to humans in large quantities, but when used in a mortar shell or as part of a vehicle bomb the amounts victims might be exposed to only have temporary effects ranging from nausea to poor vision, problems breathing and so on. Since most of the ISIL leadership also belonged to the pre-2008 Iraqi al Qaeda movement they are apparently familiar with similar tactics used back in 2006-8 and content to use this sort of thing simply to terrorize their foes.
Back in 2006-8 there were over a dozen suicide bombing attacks in Iraq that featured the use of chlorine. These were recognized as attempts to use chlorine as a chemical weapon. These efforts were unsuccessful, despite the fact that the first chemical weapon attack in modern history, in 1915, used 168 tons of chlorine gas. Then, as now, chlorine proved to be an inefficient chemical weapon and was quickly replaced by more effective ones in 1915. This is what has people worried back in 2007. The Islamic terrorists also noted the ineffectiveness of their chlorine use in bombs, and intel monitoring picked up lots of chatter about obtaining more powerful chemical weapons. Then, and now, there are still many people in Iraq, and most are Sunni Arabs, who know how to manufacture more lethal chemical agents (like mustard gas, which burns skin, eyes, or your lungs, if you inhale it). It appears that ISIL has revived the 2007 effort, perhaps using the same chemical weapons experts from the pre-2003 Saddam Hussein era. Turning all this into a super-weapon is very difficult.
The problem with these chemical weapons, from a military point of view, is that the stuff wounds and demoralizes more than it kills. This was discovered during the first major uses of chemical weapons in World War I (1914-18). Troops were so distracted by the effects of chemical weapons that they tended to forget about fighting and instead concentrated on getting out of the way of the chemical weapons and dealing with the injuries. The generals did not like the way chemical weapons destroyed military organization and discipline and were willing to go along with post-war treaties that outlawed the use of such weapons. But they were still stockpiled by the major powers, in case someone else used them. Someone else did, during the Iran-Iraq war (1980-88), where the demoralizing effects of mustard and nerve gas disorganized and demoralized the more powerful Iranian army, and saved Saddam from defeat. For terrorists, of course, chemical weapons are an excellent tool if you can get them to work.
While the Sunni Arab terrorists in Iraq have access to people who know how to manufacture mustard and nerve gas, actually doing it is rather difficult. Then, there is the problem of blowback when you do use the stuff for terrorist attacks, and the images of civilians, especially children, injured by these weapons, reach a wide audience. Back in 2007 the chatter among Sunni Arab terrorists, and their supporters, made mention of all this, and apparently no one felt confident enough to "go chemical" in a big way.
Apparently the “chemical option” was not forgotten and someone in ISIL appears eager to revive it. ISIL has not captured any chemical plants capable of manufacturing the deadlier World War I chemical weapons and building such a manufacturing capability from scratch is very difficult and likely to be detected. The chemical threat from ISIL is, however, no longer just theoretical.
The Kurds, who have been on the receiving end of most of these chemical attacks, are taking no chances and have warned their troops in front line positions vulnerable to mortar attack. New deployment tactics have been used and their American military advisors have called in chemical warfare experts and requested some basic protective gear and chemical analysis gear, just in case.