Romano on Pearlman and Atzili, 'Triadic Coercion: Israel’s Targeting of States That Host Nonstate Actors'

Wendy Pearlman, Boaz Atzili
David Romano

Wendy Pearlman, Boaz Atzili. Triadic Coercion: Israel’s Targeting of States That Host Nonstate Actors. Columbia Studies in Terrorism and Irregular Warfare Series. New York: Columbia University Press, 2018. Map, graphs. 384 pp. $65.00 (cloth), ISBN 978-0-231-17184-7.

Reviewed by David Romano (Missouri State University) Published on H-Diplo (March, 2020) Commissioned by Seth Offenbach (Bronx Community College, The City University of New York)

Printable Version: 

We often hear about how the post-Cold War decline of inter-state wars witnessed a concurrent rise in civil wars and the activities of militant non-state actors. Non-state militarized actors often enjoy the support and patronage of recognized states. They also typically use weak or failing states’ territories as a base of operations and sanctuary.

While recent work in security studies has therefore examined the difficulties involved in deterring non-state actors, this work examines a related issue: triadic coercion.[1] Triadic coercion, as the authors explain, occurs when “one state uses military threats and/or punishments against another state to deter it from aiding or abetting attacks by nonstate actors from within its territory or to compel it to stop such violence” (p. 1). When states targeted by non-state actors fail to eliminate them or deter them, and when diplomatic options with state backers of the non-state actors are unsuccessful or not an option, then states can be expected to turn to triadic coercion to solve their security problem.

With a long history of attacks from non-state actors, the Israeli state offers a rich case study for the authors to focus on. From Palestinian guerrillas to various Islamist groups, Israel has grappled with attacks from non-state actors since the founding of the state in 1948. Depending on the situation and time period, Israeli state policies to deal with the problem have varied. Sometimes the Israelis limited themselves to targeting hostile non-state actors directly, while in other instances they resorted to triadic coercion. The authors offer readers a clear, well-sourced, and eminently readable analysis of Israel’s history of triadic coercion, from the 1950s to the present. They also include a short (and correspondingly less satisfying) chapter applying the same analytical lenses to other illustrative cases (India’s efforts to deal with Kashmir and Turkey’s efforts to deal with Kurdish militants) in order to test the generalizability of their theories.

This book focuses on two related but distinct questions regarding triadic coercion: First, when and why do states resort to this policy? Second, when is triadic coercion successful and when does it appear doomed to fail? For the first question, most of the authors’ arguments indicate two basic reasons explaining the decision to coerce other states hosting or supporting hostile non-state actors: because triadic coercion works in some instances (a simple rational calculus on the part of coercing state decision makers) and because a “strategic culture” can emerge, which places value on military coercion of host/supporting states for its own sake, irrespective of whether or not such coercion will achieve desired outcomes (p. 15). The book then devotes the majority of its pages to arguing how in the Israeli case, a strategic culture frequently led to less than rational policies: “Israel aimed threats and strikes against regimes that were feeble, fragmented, and, at some junctures, hardly stronger than the nonstate actors that they ‘hosted.’ Nevertheless, Israel increasingly defended triadic coercion on the grounds that these regimes should act as responsible sovereigns; it did not soundly assess that they could. Triadic coercion thus evolved to represent an article of faith and conviction as much as a calculated strategy. Pounding host states stood nearly as an end in itself” (p. 21).

Which leads us to the second question: when does triadic coercion succeed or fail? Assuming that the coercer can, given the prevailing balance of power, credibly threaten the host state, the answer depends on the host regime’s strength. Although the authors provide a causal graph on page 8 that also includes whether or not the host state is defiant via-à-vis the coercer or cooperative, this does not really matter for determining the outcome of triadic coercion: in both cooperative cases (where the host state wants to put a stop to the non-state actors’ attacks) and defiant ones (where the host state sympathizes with and supports the non-state actors), strong regimes respond to coercion by containing non-state actors in order to protect themselves, while weak regimes get clobbered by the coercer but can do little to stop either the coercer or the non-state actors.

The logic here can perhaps best be understood via examples from the book. Although Israel repeatedly struck Syria in the early to mid-1960s (a “defiant” but weak regime at the time) and Lebanon in 2006 (a “cooperative” but also weak regime), neither was in a position to stop Palestinian guerrilla attacks (in the 1960s Syrian case) or Hezbollah attacks (in the post-1983 Lebanese case) into Israel. Strong regimes, in contrast, could and did respond to triadic coercion from Israel by putting a stop to non-state actors’ cross-border attacks, such as in the case of Hafez al-Assad’s 1970-2011 Syria and Gamal Abdel Nasser’s 1956-67 Egypt. These stronger regimes did not wish to get dragged into a war with Israel at a time not of their choosing. Despite their sympathy and support for non-state actors fighting Israel, they therefore acted to put a stop to incursions over their shared borders with Israel.

The argument regarding outcomes of triadic coercion is both compelling and fairly simple to make. Most of the book’s pages are therefore devoted to the prior question of the causes of triadic coercive policy choices and strategic culture. In short, why would Israel, at considerable international diplomatic and public relations cost, inflict pain and suffering on Lebanese and Syrian regimes unable to comply with their demands? From 1991 until 2005, Lebanon remained occupied by Syria, so how could targeting Lebanon in such a scenario pressure a less than sovereign Lebanese government to reign in Hezbollah? Additionally, further weakening of the regimes in Beirut and Damascus (during the 1960s) only compromised these governments’ ability to reign in non-state actors and therefore appeared counterproductive. The authors’ answers to these questions center on Israeli decision-making, which became dominated by military rather than civilian leaders, and the “cult of the offensive” that viewed such coercion of host states as a moral imperative as much as a strategic necessity: “Israel’s use of both massive force and triadic coercion was encouraged by regard for the inherent, as opposed to instrumental, utility of actions in pursuit of deterrence; a lack of nuance in distinguishing among different actors, glossed over as a monolithic adversary; an emphasis on the logic of appropriateness, rather than strategic outcomes, as a criterion for adopting military strategy; and an emotion-laden calling for severe punishment to burn into enemies’ ‘consciousness’ a fear of Israel’s might and resolve. These tendencies elevated moralistic convictions and dubious assumptions at the expense of measured calculations about the costs and benefits of military force” (p. 216).

It is here that I remain somewhat unconvinced of the authors’ causal arguments. There exists a better, more easily perceivable explanation for when Israel resorted to military coercion against neighboring states and when it did not. “Strategic culture” seems to be a spurious causal variable or at best an intervening variable. The better explanation can ironically be found in the aforementioned graph of triadic coercion outcomes: cooperative regimes, whether strong or weak, were not targeted militarily by Israel while “defiant” ones, again irrespective of regime strength, were. For this reason, Israel did not target the Jordanian regime or Egypt after 1979, despite cross-border attacks from both countries. It did target Lebanon after it fell under Syrian hegemony from 1991 to 2005 (with the Israelis viewing Lebanon as just a part of Syria at this point) and then under Hezbollah domination after 2005. The logic here would appear twofold. First, weakening a hostile regime may appear good for promoting security, whether or not this will stop non-state actors (which would explain targeting Syria in the 1960s in particular, just prior to the 1967 war), and non-state actors’ attacks provide a great excuse to do so. Second, domestic politics may demand military strikes following attacks from over the border. The authors unfortunately make only brief or implied references to the domestic political motivators for Israeli coercive policies, but these appear central for an electoral democracy like Israel.

In the 2006 Lebanese case, triadic coercion also appears to have worked; there have been very few Hezbollah attacks on Israel since the 2006 Lebanon war in which Israel targeted not only Hezbollah but also Lebanese infrastructure in general. The authors address this issue, citing Hezbollah leader Hassan Nasrallah’s statement that “had he known that abducting Israeli soldiers would lead to a war of the magnitude it did, he would ‘absolutely not’ have endorsed the kidnapping” (p. 213). Yet they somehow miss the point that while other elements of the Lebanese government (and army) remain unable to control Hezbollah, Hezbollah came to dominate the Lebanese government in 2006 and Hezbollah does maintain command and control over itself. An Israeli strike on Lebanon in such circumstances begins to look less like triadic coercion than regular coercion and deterrence, with an effective outcome since 2006.

The example of Turkey in chapter 7 of the book can further illustrate this point. Unlike Israel vis-à-vis its Arab neighbors, Turkey has never been at war with any of its neighbors to the south and east. Far from being “defiant” actors on the Kurdish issue, Iran and Iraq as well as Syria after 1998 even had agreements with Turkey allowing it to enter their territory in “hot pursuit” of Kurdish guerrillas. Iran, Iraq, and Syria likewise shared Turkish concerns regarding Kurdish irredentism. When such diplomatic options exist with cooperative neighboring states, triadic coercion simply does not make sense. Even the Kurdistan Regional Government of Iraq since it emerged in 1991 does not qualify as “defiant,” having succumbed to Turkish pressure since the early 1990s to help contain and at times (in the case of the Kurdistan Democratic Party of Iraq) even fight the Kurdistan Workers’ Party (PKK) militants based in the rugged mountains of Iraqi Kurdistan. Whatever its “strategic culture,” if Israel had the non-military options Turkey enjoyed to evoke cooperation from neighbors against non-state actors attacking it, it stands to reason that they would have pursued them (as they did with Jordan on many occasions and Egypt after 1979). Yet Israel could not cut off electricity to a neighboring state as Turkey did repeatedly to the Kurdistan Region of Iraq (KRG) from 1991 to 2003, nor could it threaten trade sanctions or other diplomatic measures as Turkey could with Iran and Iraq. Israel was already in a state of war with Lebanon, Syria, pre-1979 Egypt and pre-1995 Jordan. This limited its options, yet it still refrained from targeting relatively cooperative regimes over the issue of non-state actors’ attacks. The Turkish case in this sense does not appear very analogous to the Israeli one.

The one instance where Turkey did resort to significant triadic coercion actually seems much more aggressive than the prudent, careful, and defensive posture the authors paint for Ankara. In 1998, Turkey massed tens of thousands of troops on the Syrian border, threatening to start a war with Syria should it continue providing safe haven to the PKK and its leader. The authors cite this as the exception that proves the rule for Turkey (and a successful use of triadic coercion given the Assad regime’s strength at the time). It seems to me, however, that Turkey chose the “nuclear option” with a state it was not at war with. That it did so successfully still does not point to a “strategic culture” that is much more restrained or pacifist than the Israeli one. By the same token, it does not take too much imagination to think of what Turkey would do to the KRG, very quickly, should it one day announce its support for the PKK. Turkish tanks would, in all likelihood, be rolling into Erbil within hours.

Finally, the cases of India and Pakistan also seem too different to compare to Israel in terms of the choice to engage in triadic coercion. The issue of Kashmir and non-state actors’ attacks only really took off in the 1990s. This is also around the time Pakistan joined its Indian rival in the club of nuclear armed states. One would expect a lot fewer attempts at military coercion between two states possessing nuclear weapons. Additionally, Pakistan and India both enjoy much larger populations and strategic depth than Israel, with non-state actors’ attacks mostly occurring in remote Kashmir province. This would make it a lot easier for India to be patient and reserved toward provocations over the border with Pakistan. In cases when non-state actors attacked Indian cities like Mumbai, India did resort to triadic coercion (unsuccessfully). In such rare cases of Indian triadic coercion, however, the authors do make a convincing case as to why such policies failed: the Pakistani regime simply lacks the unity and strength to deal with non-state actors operating out of their territory.

Despite my reservations regarding “strategic culture” as an explanatory variable, it seems hard to argue with the authors’ point that more theoretical attention needs to be paid to triadic coercion in general. State decision makers are engaging in triadic coercion, and it behooves everyone to examine the logic behind such policies and their likely results as carefully as possible. In this regard, the authors of Triadic Coercion offer all of us an exceptionally interesting, informative, and well-crafted starting point.


[1]. See, for example, Andreas Wenger and Alex Wilner, eds., Deterring Terrorism: Theory and Practice (Stanford, CA: Stanford University Press, 2012).

Citation: David Romano. Review of Pearlman, Wendy; Atzili, Boaz, Triadic Coercion: Israel’s Targeting of States That Host Nonstate Actors. H-Diplo, H-Net Reviews. March, 2020. URL:

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