In recent months, insurgents in Iraq have begunusing chlorine gas attacks against Iraqi security forces and civilians, as well as coalition troops. This development has generated fears that the insurgents plan to conduct a sustained chemical warfare campaign in Iraq. Although the attacks have killed fewer people than conventional suicide bombs, the use of chlorine cylinders in improvised explosive devices (IEDs) marks a new phase in the insurgency. In addition, the escalation in Iraq has increased concerns that non-state actors will use chemical weapons (CW) in other countries.

The Saddam Legacy
The behavior of Iraq during the past two decades shows that the principles of deterrence that have proved generally effective against Western states do not necessarily apply to rogue states or non-state actors. Under Saddam Hussein, the government of Iraq, which never joined the Chemical Weapons Convention banning the production of chemical armaments, developed a major chemical weapons infrastructure. The government developed chlorine gas and also used chlorine to manufacture other CW agents. During the 1980s, the regime killed thousands of people by repeatedly employing chemical weapons against both foreign (Iranian) and domestic targets—most infamously in the March 1988 mustard gas attacks on the Kurdish village of Halabja. [2] The insurgents’ use of chlorine weapons in the present conflict has coincided with the closing phases of the trial in Iraq of Ali Hassan al-Majid, a former senior Iraqi official also known as “Chemical Ali” for his leading role in Saddam’s chemical weapons attacks. [3]

Major Incidents
The first recorded chlorine attack by Iraqi insurgents occurred on January 28, 2007. Suicide bombers killed 16 people by detonating a truck laden with explosives and a chlorine tank in the town of Ramadi in the al-Anbar province. Since then, insurgents have employed approximately a dozen vehicle-borne IEDs containing chlorine. Besides detonating the chlorine tanker trucks, the insurgents have also used dump trucks, pickup trucks, and standard-size automobiles rigged with conventional explosives and chlorine canisters varying in capacity from dozens to hundreds of gallons. [4] As demonstrated by their shifting tactics against coalition helicopters and armored vehicles, the Iraqi insurgents’ chemical attacks illustrate their repeated ability to adopt tactical innovations for broader use once they have proven successful. [5]

Although most of these instances have occurred in the Sunni-stronghold of al-Anbar province, the insurgents have also used chlorine bombs elsewhere. On February 20, they detonated chlorine IEDs in the northern part of Baghdad and near Taji, a town about 20 miles to the north of the capital. These attacks killed nine people and wounded 148 civilians, many of them children.

The most extensive chlorine attack occurred on March 16, when suicide bombers detonated mixtures of chlorine and conventional explosives at three separate locations in al-Anbar. The independent Iraqi news channel al-Sharqiyya gave extensive coverage to the day’s carnage. The first attack occurred in the afternoon, when insurgents detonated a pickup truck at a security checkpoint near Ramadi. The only casualties were the security personnel stationed there. The second attack near Falluja occurred when the insurgents detonated a dump truck. The attack killed only two police officers, but induced sickness among almost a hundred civilians present in the area. A third suicide explosion occurred when insurgents exploded another dump truck, with a 200-gallon chlorine tank, in a town controlled by the Albu ‘Issa tribe, whose leaders had recently begun cooperating with Iraqi security forces against al-Qaeda. [6] The device sickened 250 local civilians.

Possible Motives
The decision by some insurgents to use chlorine attacks may have resulted from their familiarity with chemical warfare under Saddam. It could also reflect a possible perception that such attacks, or threats of such attacks, might prove especially effective—at least in inducing panic—given the experience of many Iraqis with the devastating effects of chemical weapons used during Saddam’s reign. Unlike other chemicals potentially used in weapons, chlorine is a colored gas, which increases the likelihood that the gas would be visible to intended victims, causing increased fear. [7] Militants in Tal Afar have circulated leaflets threatening chemical attacks against local Sunnis who refused to leave the town. [8] Furthermore, the frequent targeting of the Iraqi police reflects a likely intent to intimidate that force and discourage its potential recruits. [9]

According to Lieutenant General Ray Odierno, the Commander of the Multinational Corps-Iraq,insurgents in Iraq have been trying for several years to incorporate different types of harmful chemicals into vehicular-borne IEDs. [10] In September 2006, the alleged new leader of al-Qaeda in Iraq, Abu Hamza Al-Muhajir, called on scientists to help the insurgents develop and employ unconventional weapons against U.S. military facilities in Iraq. [11] On January 10, 2007, the Salahaldin Al-Ayoubi Brigades, the military wing of the insurgent group Islamic Front of the Iraqi Resistance, released a video that purportedly depicted the use of rockets armed with a “chemical substance” in an attack on an American base near the Iraqi city of Samarra. [12]

Brigadier General Qasim Atta al-Musawi, the Iraqi military spokesman, attributed the incident to “takfiri terrorists.” The term “takfiri,” which literally means “those who condemn others as ‘unbelievers,’” usually refers to members of the al-Qaeda Organization in Iraq or, more generally, to foreign Muslim volunteers who came to Iraq to combat Coalition and Iraqi government forces. The al-Qaeda Organization in Iraq, however, has not claimed responsibility for the January 10 attack on any of its websites.

The fact that many of the recent attacks have occurred in the predominately Sunni-populated al-Anbar province may confirm expectations that the security crackdown in Baghdad has displaced insurgent operations into other regions. It is also possible, however, that the al-Anbar operations may be part of a terrorist campaign by Sunni insurgents against formerly sympathetic local sheiks who have turned against the guerrillas in recent months because of the high casualties their suicide attacks have inflicted on local civilians. [13] Al-Anbar province is home to Iraq’s powerful Sunni Arab tribes. Many of them oppose the U.S. presence in their country, but some tribal leaders have recently attempted to oust al-Qaeda forces from their territories after having reached an agreement with the Iraqi government.

Many Iraqi and foreign experts interpreted the attacks as al-Qaeda’s retaliation for the tribal cooperation with the government. According to Major General Michael Barbero, Deputy Director for Regional Operations at the Joint Staff (J-3), in al-Anbar province, the insurgents’ “murder and intimidation campaign has backfired.  So maybe they’re trying a different tactic in order to achieve their end.” [14] There is evidence, however, that this tactic also may have, at least partly, backfired. An independent Sunni insurgent group, the Islamic Army, has turned on al-Qaeda in Iraq after accusing it of “killing innocent people with gases like chlorine.” [15]

Sources of Supply
The widespread availability of chlorine in Iraq probably explains why the chemical has become an attractive weapon for some insurgents. Explosive expert Ali Assaadi said that there are many venues through which chlorine can be obtained; for example, from former Iraqi army warehouses, many of which have been looted. [16] He also pointed to the possibility that some scientists who worked for the former regime may be behind the manufacturing of the chlorine. A third option is that the chlorine is supplied to the insurgents by a foreign country. [17]

Iraqis commonly use chlorine for purifying water and as a general disinfectant. [18] Qasem al Mussawi, the spokesperson of “Operation Imposing Law” said that water treatment stations are the main source of chlorine for the terrorists. [19] Insurgents have raided nearby water purification plants to steal the chemical. [20] Iraqi General al-Musawi stated that chlorine from water purification plants was being smuggled to the armed groups. [21]

Besides these domestic sources of supply, reports indicate foreign sources may be supplying the material as well. On March 29, the independent online news service Alrafidayn said that reports had surfaced about middlemen securing a chlorine supply in Jordan. [22] The website wrote, “These suppliers provide the terrorists in Iraq with it [chlorine] to carry out attacks.” It added, “There are middlemen
steadfastly working on securing chlorine gas, nitric acid, and phosphorus components for other Iraqi suppliers on very short notice.” [23] The same publication quoted eyewitnesses as saying that large quantities of these products were unloaded in the port of Aqaba in Jordan. These shipments were alleged to exceed the needs of the Jordanian market by a wide margin. The pro-Shiite news service Alnajafnews appeared to confirm these reports, writing that these chemical substances, some of which are produced in Jordan, were exported to Iraq and delivered in the provinces of al-Anbar and Salaheddine. The shipments, it claimed, are sent to Iraq using official documentation and are not usually inspected at the Iraq-Jordan border since they are considered to be commercial goods. [24] In April 2007, the Iraqi Interior Ministry similarly stated that Iraq’s intelligence services had identified foreign traders, based outside of Iraq, who had been smuggling chlorine to terrorist groups. [25]  

Intercepting convoys on the dangerous roads of Iraq is another way for terrorists to secure a chlorine supply. The moderate London-based daily Asharqalawsat quoted Iraqi officials at the Ministry of Public Works saying that, “An armed group stole 160 tons of chlorine when they attacked a convoy of trucks coming from Syria in the Sunni province of al-Anbar.” [26]

Iraqi Government Countermeasures
In response, Iraqi government officials have begun organizing armed guards for truck convoys transporting chlorine. [27] On April 16, Alnajafnews wrote that Iraqi customs officers had stopped 12 trucks transporting the gas at the Iraqi-Jordanian Tareebeel border check point to ensure that the chemical substance could be escorted and safely transported to its intended recipients in Baghdad. [28] In addition, in response to the leaflets threatening chemical attacks, the authorities in Tal Afar have imposed bans on vehicular traffic. [29]

Iraqi security and coalition forces and the Iraqi government have also taken measures to mitigate the impact of the chlorine attacks. The liberal Egyptian-based news service Elaph reported that the Iraqi Ministry of Interior called on Iraqi citizens to follow a number of strategies to reduce risks in the event of an attack. These strategies include: leaving the contaminated area and heading immediately towards an area with clean air, avoiding crowding in incident areas and following instructions given by the civil defense units, going to a room with small openings, and avoiding providing mouth-to-mouth resuscitation to those who have been exposed to chlorine gas. [30]

The Arabic news wire service, Almoheet, reported that the government is also considering drastic limitations on chlorine use and possibly a complete ban of the chemical substance. [31] A civil defense officer said, “Chlorine use is exclusive to the water treatment department, which is state-run and easy to control.” [32] He added that control mechanisms must be put in place to monitor the use of chlorine by private entities. Despite these efforts, Western experts believe that efforts to limit access to chlorine will prove difficult given the large quantities of the chemical present in Iraq and the country’s extensive black market. [33]

Other CW Threats Within Iraq
The insurgents in Iraq have become increasingly sophisticated in their employment of the chlorine weapons. At first, the attacks killed fewer people than conventional bombs. The explosions burned most of the chlorine gas, which is heavier than air, rather than dispersing it. In at least one case, however, the death toll might have been considerably higher if the wind had been blowing in a different direction. [34] More recently, the insurgents have altered the composition of the bombs so that, in addition to the death and casualties due to the conventional explosions, the chlorine gas itself has sickened dozens and occasionally hundreds of people with respiratory problems, vomiting, and burns. [35]

Equally worrisome, the discovery of other chemicals in the insurgents’ possession suggests they might be seeking to use other toxic substances in the hope of increasing the lethality of their attacks, especially against American troops whose gas masks and other chemical weapons defenses provide them with considerable protection against chlorine. [36] The Iraqi security services have received intelligence that insurgent groups have sought to develop even more lethal chemical substances from materials manufactured in glass and phosphate plants in al-Anbar province. [37]

In a February 20 raid, U.S. troops discovered a complex in al-Anbar province that contained propane tanks, chlorine cylinders, and vehicles being prepared as car bombs. [38] More worrisome, Army Major General William B. Caldwell IV, the chief U.S. military spokesman in Iraq, said in an interview on CNN that the cache of weapons included “all kinds of ordinary chemicals” besides chlorine. [39] In the assessment of Major General Barbero, the insurgents’ use of chlorine weapons “should not be dismissed merely as a new tactic or a trend.” He continued that the insurgents’ employment of poison gas shows that “they’ll resort to anything.” [40]

On April 8, during a joint press conference given by Iraqi General al-Musawi and U.S. General Caldwell, the former described another raid which seized chemical substances: “In the al-‘Azamiyya area 104 canisters containing toxic chlorine and 52 kilograms of ammonium nitrate were seized, in the al-Mansur area five kilograms of phosphorous were seized, and in the al-Rashid East area fifty kilograms of toxic chlorine were seized.” [41] Al-Musawi said that the canisters were found in locations believed to be used by the “takfiri” or al-Qaeda in Iraq.

On April 12, U.S. forces found 3,000 gallons of nitric acid concealed in a downtown Baghdad warehouse. [42] Although the acid can be used to manufacture fertilizer or conventional explosives, it can cause severe burns if it comes into direct contact with human skin.

The Propaganda War
Some insurgents have highlighted their use of this new weapon in their propaganda. For example, one group reportedly released a video on a jihadi website that shows people wearing gas masks, who the announcer claims, are assembling chemical warheads. [43] In contrast, media outlets controlled by the Iraqi government have sought to give the impression that the authorities are taking an active role in quelling insurgent and sectarian violence. Broadcasts have also included random interviews with people on the street, designed to depict the barbarity of the attacks and highlight public condemnation of the incidents. For example, the coverage of the February 20 attack featured interviews with the civilian victims that emphasized their pain and suffering. [44]

Intelligence Assessments
The Iraq experience could encourage anti-Western terrorists to employ chlorine and other chemical weapons against vulnerable civilian targets in other countries. In the annual FBI threat assessment delivered to the Senate Select Committee on Intelligence, Director Robert Mueller stated that the acquisition of WMD by terrorist groups “continues to be a growing concern.” In Mueller’s assessment, while terrorists may not currently possess the capabilities to produce the complex biological and chemical agents necessary to carry out a large-scale attack, “Their capability will improve as they pursue enhancing their scientific knowledge base, including recruiting scientists to assist them.” [45]

In February 2007, then Director of National Intelligence John Negroponte stated that U.S. “intelligence reporting indicates that nearly 40 terrorist organizations, insurgencies or cults have used, possessed, or expressed an interest in chemical, biological, radiological, or nuclear agents or weapons.” He added, however, that most of these groups are only able to carry out “small-scale” unconventional attacks such as employing poisons or using “improvised chemical devices” like the chlorine bombs in Iraq. [46]

Nonetheless, according to Lieutenant General Michael D. Maples, Director of the Defense Intelligence Agency, the U.S. intelligence community believes that al-Qaeda and other terrorist groups are pursuing the capability to employ biological and chemical agents such as ricin, botulinum toxin, cyanide, anthrax, sarin, and mustard gases. [47] Suicide terrorists may prove especially effective at using CW. Since they are prepared to die in the attack, they do not wear CW defensive gear or take other measures that might alert authorities to the threat. [48]

European governments have also become alarmed by the Iraqi insurgents’ use of chlorine weapons. For example, since February 2007, British police have monitored the movement of industrial chlorine as a precaution against possible efforts by terrorists or other non-state actors to hijack trucks transporting the chemical. They have also provided additional training to their drivers to help them identify potential threats. [49]

Conclusion
The Iraqi insurgents will probably continue to conduct chemical attacks against the Iraqi government, especially its police corps, and Iraqi civilians. Although of limited military effectiveness, the attacks have generated much publicity and are not difficult to mount. The escalation in Iraq will likely encourage other terrorist groups, and maybe even national governments, to evaluate further the use of chemical weapons.

The chlorine attacks in Iraq also underscore the negative consequences of the growing availability of such materials to violent non-state actors, materials previously used in concentrated attacks only by states. For this reason, the Iraqi incidents will also encourage further efforts by the world’s governments to strengthen their national precautions against chemical weapon attacks and to consider further modifications in existing international arms control regimes to address these novel threats.

Richard Weitz – Hudson Institute, Ibrahim Al-Marashi – Koc University, and Khalid Hilal – Monterey Institute Center for Nonproliferation Studies