Do You Think Terrorists Would Use WMD (CBRNE) If They Could?
The United States faces a rising danger from terrorists and rogue states seeking to use weapons of mass destruction. A weapon of mass destruction is a nuclear, radiological, chemical, biological, or other device that is intended to harm a large number of people. The Department of Homeland Security works every day to prevent terrorists and other threat actors from using these weapons to harm Americans.
Weapons of mass destruction are typically understood to encompass chemical, biological, radiological, and nuclear (CBRN) weapons. Not all CBRN weapons, though, constitute WMD. This distinction is especially important in the case of non-state actors, since such actors often operate under severe resource constraints and are far more likely to plan or implement smaller-scale chemical, biological, or radiological attacks that fall below the WMD threshold. These smaller scale attacks might very well be disruptive and psychologically potent, but would not yield the casualty levels or physical destruction generally associated with a WMD. When we speak of the threat of terrorists and other violent non-state actors (VNSAs) using WMD, we imply CBRN weapons that, if used, would inflict catastrophic casualties, widespread social disruption, or devastating economic consequences beyond those resulting from all but the largest conventional attacks.1 By this definition, only nuclear weapons are unequivocally WMD; for chemical, biological, and radiological weapons the precise amount, nature, and sophistication of specific attacks determine whether or not they meet the WMD threshold. It is thus important to note the significant differences in use and deployment between chemical, biological, radiological, and nuclear weapons. For example, the motivations behind and capabilities required for the use of a nuclear weapon, considered a “low probability, high consequence” event, are wildly different than an attack employing toxic chemicals. Along these lines, a second salient distinction emerges—between a harm agent and a weapon. A weapon requires the pairing of a harm agent with a delivery system; this can be termed “weaponization.” The scale of the harm from toxic chemicals, pathogenic microbes, and ionizing radiation is almost wholly dependent on the efficiency with which the harm agent is delivered to the intended target(s). Delivery systems can range from the decidedly crude (the use of sharpened umbrella points to poke holes in plastic bags filled with sarin nerve agent by the Japanese Aum Shinrikyo cult in 1995) to the extremely sophisticated (the M34 cluster bomb, a U.S. Army munition designed to cover a broad area with sarin). The distinction between agent and weapon is less important in the context of state-level WMD programs since countries rarely invest in the production of a CBRN harm agent without simultaneously developing an effective means of delivery, as seen in the recent parallel development of North Korea’s nuclear and intercontinental ballistic missile programs. For non-state actors, the delivery mechanism often presents technical obstacles and resource requirements above and beyond those associated with the harm agent itself. A terrorist might successfully acquire a harmful radioisotope like cesium-137 or a pathogen like bacillus anthracis, but this does not necessarily mean that the terrorist can deliver it to a target with enough efficiency to inflict damage meeting the WMD threshold.
Terrorist groups have often shown interest in developing CBRN weapons. A CBRN weapon can consist of multiple components, including the payload (CBRN agent), the munition (protects the CBRN agent), a delivery system, and a dispersal system (such as an aerosol) (Paul Cruickshank, 2017). This process is termed “weaponization.” A precursor substance may also be needed for the production of some chemical and biological agents. These are usually dual-use materials that have a military and legitimate civilian application. The CBRN agent is the actual substance that can result in incapacitation, injury, or death for those exposed to it. To weaponize chemical materials, a terrorist can produce an agent using a precursor and employ an appropriate delivery mechanism (Columb Strack, 2017). The simplest types of chemical weapons (CW) involve the release of highly volatile or gaseous chemicals such as chlorine gas or hydrogen cyanide. Certain toxic chemicals can be produced in weapons-usable quantities with less specialized equipment than is needed for other agents. Therefore, small to medium scale chemical attacks have been the most common CBRN weapon type utilized by terrorist groups. However, creating weapons of mass destruction would require considerable volumes of these types of agent. Another option available to terrorists is the production of highly toxic, traditional chemical warfare agents (CWAs). Since 2014, there have been examples of attacks by Islamic State (IS) using sulfur mustard agents. However, nerve agents, such as tabun, sarin, and VX, require a more advanced level of expertise to ensure safety during the manufacturing process and maximum effectiveness when deployed. Terrorist groups may acquire nerve agents when unstable states lose control of chemical weapons. Although IS is believed to have gained access to nerve agents when it captured territory in Syria and Iraq in 2014, there is no evidence that it used these weapons.
All in all, The threat of WMD terrorism is a significant concern in the US Homeland and in the many locations of US presence abroad. In the Department of Defense’s Level I Antiterrorism Training, the Chairman of the Joint Chiefs of Staff states,”…be aware that the international terrorist network may exist in the area where you’re stationed or where you travel, both in and outside of the country…make security a part of your routine…patience and persistence are the watchwords for defeating the terrorists…these terrorists are patient and cunning…”
Paul Cruickshank, “A View from the CT Foxhole: An Interview with Hamish De Bretton-Gordon, Former Commander of U.K. CBRN Regiment,” CTC Sentinel 11, no. 7 (August 2017): 5-9
Breaking Bad fan jailed over Dark Web ricin plot,” BBC News, September 18, 2015, https://www.bbc.com/news/uk-england-34288380.
Europol, “European Union Terrorism Situation and Trend Report 2015,” 2015, 12, https://www.europol.europa.eu/activities-services/main-reports/european-union-terrorism-situation-and-trend-report-2015.
Columb Strack, “The Evolution of the Islamic State’s Chemical Weapons Efforts,” CTC Sentinel 10, no. 9 (October 2017): 19-23, https://ctc.usma.edu/the-evolution-of-the-islamic-states-chemical-weapons-efforts.
Jerrold M. Post, "Differentiating the Threat of Chemical and Biological Terrorism: Motivations and Constraints." Peace and Conflict: Journal of Peace Psychology 8, no. 3 (2002): 187-200.