Instrumentally, militant groups should seek to maximize their power against governments by forming alliances. However, studies in bargaining theory predict that alliances between militants would suffer from commitment problems. This study seeks to identify the conditions under which militant groups overcome these acute commitment problems and form alliances. Two game theory models of alliances amongst militants are presented, the first capturing bilateral co-operation, and the second under conditions of asymmetry. It may be concluded that while militants less susceptible to government repression should prefer bilateral alliances, vulnerable militants are more likely to form asymmetric alliances involving state sponsors. Following the theoretical predictions, the theory is tested empirically using the UCDP/PRIO data.
The University of North Carolina – Chapel Hill (email:
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4 Byman, Daniel, Deadly Connections: States that Sponsor Terrorism (Cambridge: Cambridge University Press, 2005)
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5 While the conventional definition of alliances requires a formal contract, we loosen the definition by considering any security co-operation, be it formal or informal, as a type of alliance. This is necessary largely due to the relative lack of codified agreements among non-state actors.
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9 Throughout this analysis, we draw parallels between alliance formation amongst militants and alliance formation amongst states. Although one could argue that these are different entities, we believe in applying game theory, there is no qualitative difference between states and non-state actors. Whether there is a difference is an empirical question, which we seek to address in our statistical test.
10 Byman, Daniel, Chalk, Peter, Hoffman, BruceRosenau, William and Brannan, David, Trends in Outside Support for Insurgent Movements (Santa Monica, Calif.: RAND, 1999)
11 We acknowledge that this model greatly simplifies these conflicts. It is possible that in some cases, there are either more than two groups or more than one state involved. It is also possible that, in a particular case, one of the factions may be a splinter group, or that the groups may co-operate under an umbrella organization. However, to allow the models to develop clear empirical implications, we simplify the model to three players, and assume that each group is distinct from one another. This substantively excludes splinters from the analysis, though the analysis does speak to cases where various groups consider whether to ally under an umbrella organization.
12 Lichbach, Mark I., The Rebel's Dilemma (Ann Arbor: University of Michigan Press, 1995)
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13 Conybeare, John A., ‘Arms Versus Alliances: The Capital Structure of Military Enterprise’, Journal of Conflict Resolution, 38 (1994), 215–235
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Morgan, T. Clifton and Palmer, Glenn, ‘To Protect and Serve: Alliances and Foreign Policy Portfolios’, Journal of Conflict Resolution, 47 (2003), 180–203
14 A report by Anand Gopal suggests that while the Quetta Shura favours an Islamic emirate, the Haqqani network's preference appears to be for an Islamic Republic. Reports also indicate that though he was once a member of the Taliban government, Haqqani complained about the heavy-handedness of the Taliban. See Anand Gopal, ‘The most deadly U.S. foe in Afghanistan’, Christian Science Monitor, 31 May 2009, p. 1; http://www.csmonitor.com/World/Asia-South-Central/2009/0601/p10s01-wosc.html
15 For more information on the Quetta Shura and the Haqqani Network, see David Clark Scott, ‘What is the Quetta Shura Taliban and Why Does it Matter?’ Christian Science Monitor, Global News Blog, available at: http://www.csmonitor.com/World/Global-News/2010/0224/What-s-the-Quetta-Shura-Taliban-and-why-does-it-matter; and Anand Gopal, Mansur Khan Mahsud and Brian Fishman. ‘Inside the Haqqani Network’, Foreign Policy. The AfPak Channel: Inside the War for South Asia. http://afpak.foreignpolicy.com/posts/2010/06/03/inside_the_haqqani_network_0.
16 Lake, Entangling Relations, pp. 35–77
17 Arguably, this is the strategy pursued by the United States in the Afghan conflict against the Quetta Shura and the Haqqanis. See Dexter Filkins, ‘Taliban elite, aided by NATO, joint talks for Afghan peace’, 19 October 2010. p. A1. http://www.nytimes.com/2010/10/20/world/asia/20afghan.html?_r =1&pagewanted = 1
18 We acknowledge that this model greatly simplifies these conflicts. It is possible that in some cases there are either more than two groups or more than one state involved. It is also possible that in a particular case one of the factions may be a splinter group, or that the groups may co-operate under an umbrella organization. However, to allow the models to develop clear empirical implications, we simplify the model to three players, and assume that each group is distinct from one another.
19 The game assumes complete but imperfect information. Each player's utilities are represented by Von Neumann–Morgenstern utility functions.
20 To allow for generalizability, we assume that the concession may substantively represent the granting of territory to the group, the altering of an offensive government policy, investment in the militant group's home area, cash or any other policy concession the group is seeking.
21 Ethan Bueno de, Mesquita, ‘Conciliation, Counterterrorism, and Patterns of Terrorist Violence’, International Organization, 59 (2005), 145–176
22 For a discussion of how the probability that a game continues can serve as a discount factor, please see Evelyn C. Fink, Scott Gates and Brian Humes, Game Theory Topics: Incomplete Information, Repeated Games, and N-Player Games (Thousand Oaks, Calif.: Sage University Papers on Quantitative Applications in the Social Sciences, No. 122, 1998): and/or James D. Morrow, Game Theory for Political Scientists (Princeton, N.J.: Princeton University Press, 1994). These texts indicate that since probabilities and the traditional discount factor are both bounded between 0 and 1 they are equivalent in infinitely repeated games. It is also important to note that the parameter δ in this game is different from the traditional discount factor, and is used here to represent the discount on the payoff for each player if they co-operate.
23 Bapat, Navin, ‘Insurgency and the Opening of Peace Processes’, Journal of Peace Research, 42 (2005), 699–717
Cronin, Ending Terrorism, pp. 28–47
Jones and Libicki, How Terrorist Groups End, pp. 9–44
24 Ethan Bueno de, Mesquita and Dickson, Eric, ‘The Propaganda of the Deed: Terrorism, Counterterrorism, and Mobilization’, American Journal of Political Science, 51 (2007), 145–176
25 Since both p and q are probabilities, they must be bounded between (0,1). Therefore, assume that if βp > 1, βp = 1 and if βq > 1, βq = 1. This substantively does not change the result. It indicates that in this situation, if a group is betrayed, the probability that they will be disarmed is equal to 1.
26 This conclusion is very similar to Bueno de Mesquita, ‘Conciliation’.
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Lake, Entangling Relations, pp. 35–77
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29 Conybeare, ‘Arms Versus Alliances’, pp. 215–235
Lake, Entangling Relations, pp. 35–77
Morrow, James D., ‘Alliances, Credibility, and Peacetime Costs’, Journal of Conflict Resolution, 38 (1994), 270–297
30 Byman, Deadly Connections, pp. 155–186
31 This would further suggest that since both the Quetta Shura and the Haqqani Network were initially quite vulnerable to collapse at the hands of the US military following Operation Enduring Freedom it is likely that parts of Pakistan's government assisted the groups in banding together.
32 Byman, Deadly Connections, pp. 155–186
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34 Victor Asal, Hyun Hee Park, Karl Rathemeyer and Gary Ackerman, ‘With Friends Like These … Why Terrorist Organizations Ally’ (paper presented at the International Studies Association Meeting, 2010).
35 We currently lack a reliable measure of the ideological compatibility of the militant groups. While one strategy might be to examine the manifestos of some of these groups, we encounter two potential problems. First, not all of the groups have public manifestos. Secondly, in forming an alliance, these groups might have incentives to misrepresent their true ideologies in order to make themselves more attractive alliance partners, or to signal that the alliance is stronger than it actually might be. While this is certainly an interesting area of study, we leave it for future research and focus on what we can currently test.
36 Particularly for the ethnically or religiously based conflicts, individual actors could not be identified, but it was clear that there was more than one challenger – examples of the Uppsala/PRIO coding of this are: Sikh insurgents, Palestinian factions or sectarian factions. If there was evidence of some co-operation/co-ordination among these actors, then the entire collective was coded as having formed an alliance. We do not create dyads that allow groups that are fighting separate territorial conflicts to be considered alliance partners. For example, in the case of India, we have dyadic pairings for those groups that participated in the conflict in Kashmir and pairings for groups involved in Naxalite insurgency. However, we do not create dyads that consider the groups in the Kashmir conflict as potential alliance partners with the Naxalites.
37 The eighteen observations that involved major powers as target states were removed from the analysis, though the results are robust even when they remain in the dataset. However, since the major powers’ campaigns involved interventions on foreign territory (United Kingdom–People's Republic of Yemen; France–Algeria; and Soviet Union–Latvia), it is inappropriate to consider these observations to be comparable to cases where the target government was fighting multiple groups within its own territory. The exclusion of the major power observations removed 1.04 per cent of the observations.
38 The full dataset for replicating the analysis is available at: http://www.bsos.umd.edu/gvpt/bond/.
39 Byman, Deadly Connections, pp. 21–52
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Paul Diehl and Gary Goertz (War and Peace in International Rivalry (Ann Arbor: University of Michigan Press, 2000), pp. 29–34)
41 In some cases there are more than two militant groups, which allows the sponsor more than one choice of alliance to sponsor per year. However, since our data focus mainly on the government, these data would essentially repeat. For example, in the case of Israel, four sponsors could intervene to support an alliance between Hamas/Hezbollah, Fatah/Hezbollah, Hamas/PFLP, Fatah/PFLP, Hezbollah/PLFP, etc. This would require repeating data from the years in which each of these groups are active, but the data would not be independent. To keep the observations independent, the sponsorship variable is coded as 1 for this data if the potential sponsor intervenes in any of the potential alliances. We did, however, run our analyses with the repeated observations, and the results are robust to this design.
42 However, these states were not excluded from the tests of Hypotheses 1 and 2.
43 Jongman, Albert J. and Alex Peter Schmidt, World Directory of Terrorist and Other Organizations Associated with Guerrilla Warfare, Political Violence and Protest (Edison, N.J.: Transaction, 1988)
Janke, Peter, Guerrilla and Terrorist Organisations: A World Directory and Bibliography (New York: Macmillan, 1983)
44 This coding of a sponsor state provides a useful alternative to and/or extension of the UCDP/PRIO coding of ‘secondary parties’ to a conflict. While ‘secondary parties’ (variables SideA2nd and SideB2nd) are identified as state actors that enter the conflict to aid the primary actors, this aid is restricted to the military sort: ‘[S]econdary parties are states that enter a conflict with troops to actively support one of the primary parties’ (UCDP/PRIO Armed Conflict Dataset Codebook, p. 2). Our definition allows for a greater range of sponsorship activities, and includes both economic and tactical support as indicators of outside support for a militant group or alliance. Additionally, where the UCDP/PRIO data restrict the universe of potential secondary parties in a conflict to those countries that ‘share the position of the primary party it is supporting in the incompatibility’, we impose no ideological restrictions on the sponsor state by our definition.
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46 We also created a third version of the weak link variable that simply drops categories 2 and 3, and the results were robust.
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59 The results do not change if we use the first weak-link indicator as opposed to the second with the controls.
60 As a further robustness check, we re-analysed the models using all of the controls from Fearon and Laitin's 2003 study, ‘Ethnicity, Insurgency, and Civil War’. The results remain consistent and the weak-link variable along with the interaction term remain in the anticipated directions and significant.
61 The 95 per cent confidence intervals are in the parentheses.
62 Byman et al., Trends in Outside Support for Insurgent Movements.
* The University of North Carolina – Chapel Hill (email: email@example.com); and The University of Maryland – College Park (email: firstname.lastname@example.org), respectively. The authors are sincerely grateful to Kristian Gleditsch, Mark Crescenzi, Sarah Croco, Stephen Gent, Errol Henderson, Doug Lemke, Will Moore, Glenn Palmer, Todd Sandler, the Journal's four anonymous reviewers, and especially George Rabinowitz, for their exceptionally helpful comments. Data replication materials are available at http://www.bsos.umd.edu/gvpt/bond/.
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