At the ISIS/Extremism Community Briefing I gave 25 January for the Sheriff's Auxiliary, there was a discussion in Q&A about whether the removal of Osama bin Laden and other Al Qaeda lieutenants made the global terrorism situation worse. I argued that at least in some ways it did and mentioned several papers discussing the effectiveness of leadership decapitation as a counterterrorism tactic. As this is a broad policy issue rather than one of interest to the Sheriff's Office, I am going to post my response and the resources on this blog rather than on the Sheriff's Auxiliary site. Opinions here are my own, not official statements of the Sheriff's Auxiliary, Sheriff's Office, nor of any other organization.
What Is Leadership Decapitation?
Leadership decapitation is the targeted killing of top terrorist or insurgent group leaders for the purposes of destroying the command and control structure of an organization. Some authors include both capture and killing of leadership in the term. For our purposes, we focus primarily on the effects of killing such leaders and contrast it with capture or imprisonment. Drone strikes, bombings, and arranging assassinations of terrorist leaders will all fall under this general heading.
Is Leadership Decapitation Effective?
Different researchers argue about whether leadership decapitation is effective in the long term and there are certain circumstances where it may be effective. In the short term, however, decapitation has negative effects which may actually lead to escalation of violence, hardening of opposition, or fragmentation of terrorist groups into multiple independent threats.
Mia Bloom describes the struggle between terrorist groups to compete for limited funding, followers, and support, often driving a cycle of increasing extremism. If a terrorist group is not willing to embrace certain methods or approaches, such as the use of suicide terror or of women in suicide attacks, it will be outbid in the marketplace of extremism by groups with less scruples.  Leadership decapitation can feed this cycle:
If the terrorist leader can be captured, imprisoned and made to denounce his/her organization this is a proven effective strategy... In contrast to this, killing terrorist leaders appears to serve the purposes of the outbidders, creates nationalist myths, martyrs, and cults of personality. [Bloom, 2006 pp 145—146]
We can see this kind of competition between Al Qaeda and ISIS, itself a spin-off of al Qaeda [Barnard & MacFarquhar, 2015]. Leadership decapitation is partly responsible for the fragmentation of Al Qaeda into multiple competing movements. This does not necessarily preclude the possibility that a long-term reduction in violence may result, but, at least in the near-term, the effect is greater chaos.
Jenna Jordan conducted an empirical study of 298 incidents of leadership targeting from 1945—2004 which found that decapitation rarely has measurable positive results and may often be counterproductive in terms of number of attacks and attack lethality :
This finding could be explained in part by the argument that arresting members of the upper echelon is more effective because they can provide essential intelligence. Cronin argues, “There is some reason to believe that arresting a leader is more effective in damaging a group than is killing or assassinating him.” She claims that killing a terrorist leader may increase publicity for the cause and create a martyr that could then attract new members to the organization. Cronin’s argument provides a more theoretical basis for the finding that decapitation is rarely effective. An increase in publicity and sympathy can have adverse reactions. [2009 pp 736]
In her study, she details specific categories of terrorist organizations which appear to be more susceptible to decapitation than others and where it may, arguably, be effective. However, she points in the above quote to another problem with assassinating enemy leadership compared to capturing them: dead leaders produce no intelligence for future operations. This has been a consistent point of failure in US drone operations. Not only have targeted killings (e.g. drone strikes) been hampered by poor intelligence, they make the problem worse by destroying potential future intelligence before it can be gathered and analysed:
Deadly strikes thus truncate the find, fix, finish cycle without exploitation and analysis — precisely the components that were lacking in the drone campaign waged in East Africa and Yemen. That shortfall points to one of the contradictions at the heart of the drone program in general: Assassinations are intelligence dead ends. [Courier and Maass, 2015]
It should be noted that Bryan Price disputes Jordan's results in an empirical study which claims that decapitation "significantly increases the mortality rate of terrorist groups, even after controlling for other factors", particularly when looking at longer term effects [Price, 2012]. It is possible that decapitation leads to reduced longevity of terrorist organizations over the long haul, even if the shorter term result may actually be an increase in number and lethality of attacks as found by Jordan.
If leadership decapitation is an effective long-term strategy, it is not guaranteed to be so in the short term and may even be counterproductive, resulting in higher terrorism recruitment, fragmentation of threats, more and more lethal attacks, etc., before it gets better. Either way, assassinating terrorists instead of capturing them severs the intelligence cycle making future counterterrorism efforts more difficult. When we do use targeted killings of terrorist leadership, we should do so with full consideration of which organizations may be more and less susceptible, whether capture is a better alternative, and whether leadership decapitation will adversely effect future intelligence efforts. We should also make it clear to the public that the technique, even when successful, may require substantial fortitude rather than yielding instant results.
- [Barnard and MacFarquhar, 2015]
- Barnard, Anne, and Neil MacFarquhar. 2015. “Paris and Mali Attacks Expose Lethal Qaeda-ISIS Rivalry.” New York Times, November 20. http://mobile.nytimes.com/2015/11/21/world/middleeast/paris-and-mali-attacks-expose-a-lethal-al-qaeda-isis-rivalry.html.
- [Bloom, 2006]
- Bloom, Mia. 2006. “Dying to Kill: Devising a Theory of Suicide Terror. Paper for Presentation to the Harrington Workshop on Terrorism.” http://www-personal.umich.edu/~satran/Ford 06/Wk 3-2 Suicide Terrorism Bloom.pdf.
- [Courier and Maas, 2015]
- Courier, Cora, and Peter Maas. 2015. “Firing Blind: Flawed Intelligence and the Limits of Drone Technology.” The Intercept. https://theintercept.com/drone-papers/firing-blind/.
- [Jordan, 2009]
- Jordan, Jenna. 2009. “When Heads Roll: Assessing the Effectiveness of Leadership Decapitation.” Security Studies 18 (4): 719–55. doi:10.1080/09636410903369068.
- [Price, 2012]
- Price, Bryan C. 2012. “Targeting Top Terrorists.” International Security 17 (51): 9–46. http://belfercenter.ksg.harvard.edu/publication/21915/targeting_top_terrorists.html.