Effects of Defensive and Proactive Measures on Competition Between Terrorist Groups

• Author: Subhayu Bandyopadhyay,Todd Sandler
• DOI: http://doi.org/10.1177/00220027221108432
• Published date: 01 November 2022
• Date: 01 November 2022
• Subject Matter: Articles

Article

Journal of Conf‌lict Resolution

2022, Vol. 66(10) 1797–1825

© The Author(s) 2022

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DOI: 10.1177/00220027221108432

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Effects of Defensive and

Proactive Measures on

Competition Between

Terrorist Groups

Subhayu Bandyopadhyay

1

and Todd Sandler

2



Abstract

A two-stage game investigates how counterterrorism measures affect within-country

competition between two rival terrorist groups. Although such competition is

commonplace (e.g., al-Nusra Front and Free Syria Army; Revolutionary Armed Forces

of Colombia and the National Liberation Army; and al-Fatah and Hamas), there is no

theoretical treatment of how proactive and defensive measures inf‌luence this inter-

action. Previous studies on rival terrorist groups are solely empirical concerning group

survival, outbidding, and terrorism level, while ignoring the role that government

countermeasures exert on the rival groups’terrorism. In a theoretical framework,

alternative counterterrorism actions have diverse impacts on the level of terrorism

depending on relative group sizes and government-targeting decisions. In the two- stage

game, optimal counterterrorism policy rules are displayed in terms of how govern-

ments target symmetric and asymmetric terrorist groups. Comparative statics show

how parameter changes affect Nash or subgame perfect equilibrium outcomes.

Keywords

competitive terrorist groups, defensive and proactive counterterrorism, two-stage

game, comparative statics, outbidding between rival groups

1

Research Division, Federal Reserve Bank of St Louis, St Louis, MO, USA

2

School of Economic, Political & Policy Sciences, University of Texas at Dallas, Richardson, TX, USA

Corresponding Author:

Todd Sandler, School of Economic, Political & Policy Sciences, University of Texas at Dallas, 800 W. Campbell

Road, Richardson, TX 7508-3021, USA.

Email: tsandler@utdallas.edu

Introduction

Multiple rival terrorist groups may operate in the same country such as the Liberation

Tigers of Tamil Eelam (LTTE) and the People’s Liberation Army of Tamil Eelam

(PLATE) in Sri Lanka (Bloom 2005), the Revolutionary Armed Forces of Colombia

(FARC) and the National Liberation Army (ELN) (Phillips 2015), al-Fatah and Pal-

estinian Islamic Jihad (PIJ) (Bloom 2004), and Shining Path and the Tupac Amaru

Revolutionary Movement in Peru (Phillips 2015). Other notable rivalries include Moro

National Liberation Front and the New People’s Army in the Philippines, Provisional

Irish Republican Army (PIRA) and Ulster Volunteer Force (UVF) in Northern Ireland,

Hezbollah and Amal Movement in Lebanon, al-Qaida and Islamic State (IS) in Af-

ghanistan (Congressional Research Service 2022), al-Shabaab and Hizbul Islam in

Somalia, and Lashkar-e-Islam and Tehrik-i-Taliban in Pakistan. Such rivalries may

characterize some years and not others if groups come to an accommodation, merge,

end operations, or are annihilated. Moreover, rival terrorist groups in the same country

may be similar or quite different in size –e.g., Aum Shinrikyo was many magnitudes

larger in size than the Japanese Red Army (Hou, Gaibulloev, and Sandler 2020). Even

allied groups may pursue different policy outcomes (e.g., social revolution, policy

change, or territorial change), resulting in rivalry. Despite these ubiquitous rivalries,

there is no theoretical treatment of how a government should interface with such groups

when choosing its counterterrorism policies.

1

For instance, should the government rely

on defensive policies that protect vulnerable targets from all terrorist groups, or should

the government resort to proactive or offensive measures to weaken a targeted group?

In the latter case, should the government attack the stronger or weaker terrorist group?

Those and many other related questions are addressed here.

In its most elementary form, a theoretical model must have three players –the

government and two rival terrorist groups. This basic representation not only makes for

a tractable analysis, but also provides a framework that can be extended to more rival

groups and other considerations. In past theoretical work, one or more targeted

governments confront a single terrorist group, whose objective is to create maximal

damage with limited resources (Bandyopadhyay and Sandler 2011,2014;

Bandyopadhyay, Sandler, and Younas 2020;Mirza and Verdier 2014;Rosendorff and

Sandler 2004;Rossi de Oliveira, Faria, and Silva 2018;Siqueira and Sandler 2006).

When, however, there are two or more terrorist organizations operating in the same

country, their objectives are to create terror and to bolster their reputation as a relatively

stronger group. This latter aim may derive from the prospects of improved recruitment,

2

better external funding, and enhanced political inf‌luence. Those desires relate to the

notion of outbidding for which competitive terrorist groups within a nation seek,

through their attacks, to outshine their rivals (Bloom 2004,2005;Nemeth 2014). If a

rival terror group upstages its competitors, then the group may take the lead in pushing

its political agenda on the government. Terrorist groups drawn from the same ideo-

logical base may possess vastly different aims –e.g., one group may be less hard-line

than another in terms of acceptable concessions. In particular, many of the splinter

1798 Journal of Conf‌lict Resolution 66(10)