Introduction

The Arab uprisings of 2011 produced domestic, regional and international shockwaves that tested the durability of some of the world’s longest standing autocratic regimes. Four states—Bahrain, Libya, Syria and Yemen, experienced foreign military interventions in support of ruling autocrats or competing rebel factions, resulting in autocratic survival in Bahrain and internationalized civil wars in Libya, Syria and Yemen. While the pervasiveness of external interventions in the Middle East and North Africa (MENA) is interlinked with the evolution and development of the regional state system that emerged in the twentieth century (Halliday 2005; Gause 1990; Brownlee 2012; Yom 2016), the simultaneity of military interventions at the onset of mass popular uprisings in 2011 poses a theoretical and empirical puzzle.

Military interventions in Bahrain, Libya, Syria and Yemen in 2011 pose two conundrums within the extant literature on external interventions. First, interventions in support of autocratic regimes and warring rebel factions occurred at the onset of largely peaceful pro-democracy uprisings and not as a result of preexisting conflicts. Second, states in the region experienced sequential and contemporaneous interventions during the region’s largest pro-democracy wave. To address this puzzle, this article proposes a structural explanation of multi-sided foreign military interventions during the Arab uprisings of 2011. I argue that the simultaneity of region-wide mass protests altered the balance of power within and among states, producing a permissive strategic environment that heightened external actors’ proclivity to intervene militarily in the aforementioned states. Changes to the balance of power and state capabilities induced by mass popular uprisings signaled a window of opportunity for external actors to pursue competing ideational and material geostrategic interests.

The article proceeds as follows. The first section situates external interventions in the Arab uprisings within the extant literature on foreign military interventions. The second section explicates a structural explanation of military interventions that focuses on how states intervened to alter or maintain the balance of power to leverage competing forms of influence. To demonstrate how structural changes to a regional environment induce external interventions, the third section offers a cross-national analysis of multi-sided military interventions in Bahrain, Libya, Syria and Yemen to illustrate how a change in the balance of power caused by domestic shocks shaped the propensity to intervene militarily in pursuit of competing ideational and material interests. I conclude by summarizing how structural conditions within a given regional environment affect the decision to intervene militarily in states experiencing domestic unrest.

The external determinants of military interventions

Foreign military interventions often structure conflict processes as actors seek to alter the domestic environment to serve competing geostrategic interests. The literature on military interventions elucidates how, when and why external actors intervene in states experiencing civil unrest. Morgenthau’s seminal essay on great power competition and military interventionism during the Cold War illustrated how bipolarity and America’s ideological commitment to contain communism shaped its pursuit of foreign interventions even to the detriment of its own economic and national interests (Morgenthau 1967). Looking to the international environment, scholars similarly elucidated the ways in which structural conditions impel military interventions. By capturing the scope and levels of formal and informal influence in internal conflict, (Scott 1967, 196) attributed the internationalization of internal conflict to its significance to the functioning of the international system. Expounding a definition of intervention as convention-breaking and authority-oriented behavior, Rosenau emphasized three systematic variables that structured and motivated interventions: the basic structure of the international system, the degree of ideological rivalry sustaining the system and the stability of states comprising the system (Rosenau 1969, 167–168). Scholars have similarly explicated how ideological and kinship ties and affective linkages produce spill-over effects which shape the type, level and scope of foreign intervention in civil strife (Mitchell 1970, 185).

Research on military interventions suggests such interventions subvert democratization and prolong civil wars (Regan 2002; Cunningham 2010; Downes and Monten 2013). Employing various coercive tools to alter domestic outcomes, intervening states are motivated by multiple ideational and material interests that dictate the durability of intrastate conflicts. Within IR, the extant literature on foreign military interventions proliferated at the backdrop of the Cold War as the Soviet Union and the USA leveraged influence in a highly bifurcated global system (Galtung 1971; Millar 1980; Dunér 1983; O’Rouke 2019). Subsequent works have illustrated the deleterious effects of military interventions on the intensity and durability of civil wars (Pickering 2001; Collier and Sambanis 2002; Howard and Stark 2018). Others have scrutinized the link between external intervention and warring rebel factions and the intensification of civil wars (Elbadawi and Sambanis 2000; Gent 2008). Such linkages exacerbate domestic unrest especially when intervening states pursue an alternative agenda from that of domestic combatants (Cunningham 2010). Thus, the role, type and relative strength or weakness of coercive and non-coercive external linkages affect domestic outcomes (Schmitz et al. 1999; Pridham 2000; Levitsky and Way 2006; Gleditsch 2007). Advancing an actor-centric model, (Findley and Teo 2006, 830) emphasize three types of strategic relations that determine the scope of external intervention in civil wars—if states intervene in response to other interveners; the level of convergence or divergence of interests with the target government; and structural factors. Others have illustrated how external intervention is predicated on “inter-power interactions” rooted in competition and rivalry between regional power-players and great powers (Gent 2010, 1; Yoon 1997). Anderson (2019) similarly illuminates how systemic changes in the international system produce competitive interventions, which determine the duration and prevalence of civil wars.

Similarly, scholarship on foreign intervention in the MENA underscores the region’s hydrocarbon wealth and the geostrategic calculations sustaining Western influence (Yom and Al-Momani 2008; Bellin 2012; Brownlee 2012; Hinnebusch 2015). (Kinsella and Tillema 1995) seminal work illustrates how Cold War competition between the USA and the Soviet Union increased arms transfers to warring states in the region between 1948 and 1991. Scholars have detailed the relationship between American oil interests and increased militarism since the Cold War (Jones 2012). Recent works have drawn links between the strength of external linkages on autocratic survival (Ayoob 2012; Yom and Gause 2012). Others have underscored the effects of international interactions between autocrats in the region and Western powers on stalled democratization (Lynch 2016; Ryan 2018; Mako and Moghadam 2021).

The burgeoning literature on military interventions has thus illuminated the internal and external factors shaping intervenor’s foreign policy decisions in states experiencing domestic unrest (Aubone 2013). This article contributes to existing debates and demonstrates that changes to the balance of power within a given strategic regional environment provide an opportunity structure for external actors to intervene militarily to alleviate hostilities, quell unrest or bolster combatant capabilities in pursuit of competing geostrategic interests.

A structural explanation of military interventions in the Arab Spring

Identifying and mapping how systemic shifts structure changes within the international system or within a given regional state system exemplifies a perennial agent–structure problem in international relations (Wendt 1999). Treating the MENA as a penetrated regional state system (Brown 1984, 4–5), I posit that domestic instability caused by mass uprisings altered the relative distribution of power within and between states, resulting in system-wide changes to the international relations of the MENA region (Gause 1999, 28).Footnote 1 Systemic shocks transformed the balance power in a vertically differentiated, heterarchic regional state system characterized by multiple and “often tangled hierarchies… with differentially divided capabilities or authority” (Donnelly 2009, 64). Such rapid transformations signaled a clear opportunity for external states to bolster their relative balancing capabilities in an arena of high international and regional strategic competition (Ripsman et al. 2016, 47). The uprisings produced a permissive regional strategic environment that enabled external actors to leverage competing ideational and material interests through interventions in weak and fragmented states experiencing political unrest (Ibid, 52). Military interventions thus enabled external actors with different regime types, ideologies and political institutions to pursue similar strategies to balance against emerging threats or to pursue geostrategic gains (Ripsman et al. 2016, 19).

The cross-national comparison illustrates how micro-level developments rooted in state-society relations affected macro-level outcomes in states that experienced foreign military interventions in 2011. All states examined herein—Bahrain, Libya, Syria and Yemen, are divided polities with fractionalized center-periphery relations, which signaled an opportunity for external states to alter the balance of power vis-à-vis regional and international rivals through multi-sided interventions. I illustrate how historical legacies of coercive and non-coercive interventions influenced the decision to intervene militarily in places where prior ideational and material threats and opportunities structured geostrategic alignments. Thus, transformations in the balance of power and relative weakness in state capabilities induced by the 2011 uprisings in weak and fragile states presented an opportunity structure for states to exert—and maintain, interests and opportunities. Moreover, the simultaneity of the uprisings produced a window of opportunity for regional and international states to exert influence, which determined the scope and level of interventions given that the uprisings occurred and progressed within a given temporal setting, priming the opportunity structure for intervening actors.Footnote 2 As illustrated in Fig. 1, all four states experienced variable upticks in external intervention at the onset of the uprisings in early 2011. Whereas one-sided intervention at the behest of the ruling al-Khalifa monarchy in Bahrain by Saudi Arabia and the UAE swiftly restored order and quelled dissent, multi-sided interventions in Libya, Syria and Yemen produced higher levels of fragility and violence.

Fig. 1
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External intervention pre and post uprisings, 2009–2019. Source: Fund for Peace, Fragile States Index. 0 denotes low external intervention, 10 high

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Intervention here denotes convention-breaking, authority-oriented behavior directed at changing or preserving the structure of political authority in a given society (Rosenau 1969, 161). Whereas existing works on multi-sided interventions focus on power dynamics between state actors and rebel groups at the onset of, and during civil wars (Anderson 2019; Lounsbery 2016; Christia 2012; Ackinaroglu 2012), military interventions during the Arab uprisings occurred initially in the absence of conflict. As illustrated in Fig. 2, although mass protests have been an integral feature of contentious politics in the MENA, the 2011 uprisings were unique because they constituted the largest protest wave in the region’s longstanding history with mass mobilization (Lynch 2012; Mako and Moghadam 2021; Tripp 2013).

Fig. 2
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source: Clark and Regan (2016). A protest event is defined as a gathering of 50 or more people demanding action from the government. The target is the state or state policy

Protest and Mobilization in the MENA 1990–2018. Data

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To capture the scope of foreign military interventions, I distinguish between interventions in support of governments, rebel groups, opposing governments and opposing rebel groups (Pearson and Baumann 1993, 4) in Table 1.

Table 1 Intervening actors, support type and outcomes
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States intervene in internal conflict to instigate, perpetuate, heighten or settle it by providing support for political organizations, military and paramilitary groups, taking a formal position that influences the conflict such as sanctions or embargos, providing financial and economic support or penalties to warring parties, using “volunteer” forces, or to mediate disputes (Scott 1967, 197). The cross-national comparison illustrates how changes to the balance of power produced regional and international rivalry and created the opportunity structure for states to pursue competing ideational and material interests (Sørensen 2008; Sil and Katzenstein 2010; Darwich 2016).Footnote 3 Analytical eclecticism complements the cross-national comparison because it “considers the different ways in which individual and collective actors in world politics form and pursues their material and ideal preferences within given environments” (Sil and Katzenstein 2010, 21). I argue external actors, working at times in coordination with each other or independently, interacted with domestic social forces to “participate directly and authoritatively, through actions taken jointly with the society’s members, in either the allocation of its values or the mobilization of support on behalf of its goals” (Rosenau and Farrell 1966, 65).

Operationalizing the case selection

To demonstrate how changes in the regional environment propelled multi-sided interventions during the Arab uprisings, I limit the case selection criteria to countries that experienced foreign military interventions following mass protests. I illustrate how domestic vulnerabilities brought on by mass uprisings produced strategic competition between great powers and meddling regional middle powers as states sought to recalibrate their capabilities in light of emerging threats and opportunities (Saouli and Saouli 2020, 15).

Contrasting cases of non-intervention with cases of intervention warrants some explanation. Whereas Tunisia became an institutionalized democracy that has withstood political and socio-economic shocks to its nascent success, Egypt initially succeeded in toppling its autocratic government only to reverse course in 2013 following a military coup that ousted its only civilian and democratically elected government within a year of taking office. Likewise, Morocco’s February 20 Movement produced modest constitutional reforms but failed to impose tangible constitutional and democratic constraints on the ruling monarchy, resulting in static stability (Lawrence 2016). Two factors distinguish Tunisia, Egypt and Morocco from Bahrain, Libya, Syria and Yemen. First, as largely homogenous societies, protests in the first set of cases developed organically where protestors coalesced around common socio-economic and political grievances, which shaped collective demands for reform. Second, neither states endured foreign military interventions at the onset of mass mobilization, nor thereafter. Conversely, Bahrain, Libya, Syria and Yemen are all divided societies with historical legacies of intergroup conflict and foreign meddling that made the authority structures in these states more precarious and more susceptible to external intervention (Rosenau 1969, 168).

Foreign military interventions thus characterize the cross-case comparison between Bahrain, Libya, Syria and Yemen while excluding Egypt, Morocco and Tunisia from the present inquiry (Seawright and Gerring 2008, 296). The case selection fulfills two objectives. First, the cases constitute a representative sample within a given temporal setting (the Arab Spring) that endured military interventions during mass protests. Second, they represent useful variation on the dimension of theoretical interest given that military interventions produced different outcomes: The swift intervention in Bahrain succeeded in its objective to keep the autocrat in power, whereas multi-sided interventions in support of ruling autocrats and/or competing rebel factions produced internationalized civil wars in Libya, Syria and Yemen (Seawright and Gerring 2008, 296).

Swift military intervention in Bahrain

The February 14th Day of Rage uprising in 2011 posed a domestic and regional threat to the balance of power for Arab Gulf states and American strategic interests in the Persian Gulf on the one hand, and Iranian influence in the Arabian Gulf’s only Shia majority state with a history of Iranian influence and meddling, on the other. As a key ally and a bulwark against Iranian influence, Bahrain geostrategic position makes it highly dependent on military, financial and diplomatic assistance from its foreign patrons. As the only Shia-majority state in the Gulf Cooperation Council (GCC), mass protests in 2011 heightened threat perception of Iranian meddling and interference, prompting neighboring states to provide military and financial assistance to quell dissent (Mabon 2012).

On a regional level, Bahrain’s stability is entwined with that of GCC member states. The 1982 GCC agreement on security coordination and cooperation emphasizes the interdependence of GCC security, stipulating that an attack on any member state is an attack on all GCC states and foreign interference by any group in the internal affairs of one state is interference in the affairs of all member states (Gulf Cooperation Council). Fears of Iranian interference in Bahrain’s internal affairs among the country’s majority Shia population particularly following the 2003 Iraq war preceded the 2011 uprising (Wikileaks. 2005). Bahrain’s King Hamad saw the uprising as a decades-old external plot “for subversive designs” (Al-Arabiya 2011). Similarly, Minister of Defense and Commander-in-Chief of the Bahrain Defense Force, Marshall Khalifa bin Ahmed al-Kahlifa, viewed the February uprising as “by all measures a conspiracy involving Iran with the support of the United States…to draw a new map” of the region based on shared interests to undermine Arab welfare (Gengler 2011).

At the behest of King Hamad bin Isa al-Khalifa, Saudi Arabia invoked a GCC common security agreement and deployed 1000 military personnel accompanied by 500 forces from the UAE and some troops from Qatar on March 13 2011 to aid Bahraini forces in quelling pro-democracy protests (International Crisis Group 2011). In a move to placate protestor demands following the uprising, GCC states announced the creation of a Gulf Marshall Plan to boost socio-economic spending (Toumi 2011). More recently, Saudi Arabia, Kuwait and the UAE allocated $10 billion in financial aid to Bahrain to alleviate a mounting budget deficit crisis (Barbuscia 2018).

The Bassiouni Commission, an independent inquiry established by King Hamad bin Isa Al-Khalifa in June 2011, found no established link of Iranian interference in the 2011 uprisings (Bahrain Independent Commission of Inquiry 2011, 387). Nevertheless, given its socio-economic and political vulnerabilities, military and financial assistance to Bahrain from its regional allies serves the dual purpose of safeguarding the regime from internal and external security threats while enabling Arab Gulf states to balance against Iranian influence in the GCC. Foreign military intervention in Bahrain succeeded in its strategic mission of ensuring regime survival for the purpose of maintaining the balance of power of GCC states in the Persian Gulf.

Western influence in Bahrain is predicated on its geostrategic value for balancing against Iranian influence in the Persian Gulf. Both the Muharraq airfield and the Jufair naval base became strategic points for British military and diplomatic interests in the region until Bahrain’s independence in 1971 (Lawson 1989, 118). American naval presence began with the US Middle East Force in 1948, and by 1971, the USA had replaced the British Royal Navy as Bahrain’s foreign military patron. The Cold War, the Iranian revolution and the Iran-Iraq war pulled Bahrain further into America’s geopolitical orbit as a naval frontier to counter threats to America’s hegemony in the region (Ibid, 121–123). The relocation of the US Fifth Naval Fleet to Bahrain in 1995 and the military capability of its neighboring Gulf allies shields it from domestic and regional threats. Designated a major non-NATO ally in 2001 by the Bush administration to reinforce strategic and military cooperation following 9/11, Bahrain has benefited from arms purchases from the USA, including a recent purchase proposal totaling $2.48 billion (Department of Defense 2019).

Bahrain’s importance for alliance management in the Persian Gulf region shielded the monarchy from international condemnation for the use of lethal force against unarmed protestors. Then, Secretary of State Hilary Clinton justified the Obama administration’s decision to intervene militarily in Libya while withholding decisive action against Bahrain and the perils of adopting a “one-size-fits-all” policy regarding foreign intervention, noting that:

America has many important national interests in the region, and they will not always align perfectly, despite our best efforts. ‘We’ll always have to walk and chew gum at the same time.’ That was certainly true in Bahrain. America will always have imperfect partners who doubtless view us as imperfect too, and we’ll always face imperatives that drive us to make imperfect compromises (Clinton 2014, 360).

Two years following the regime’s crackdown on protests, the Obama administration reaffirmed Bahrain’s strategic importance as host of the Combined Maritime Forces (a naval security partnership of 33 nations commanded by a US Navy Vice Admiral) by adding five additional patrol coastal ships and a $580 million expansion project of the Fifth Fleet (Parrish 2013). This partnership bolsters Bahrain’s stabilizing value for American interests in the region. Likewise, while Britain’s then Foreign Secretary William Hague strongly condemned the use of live ammunition on protestors and urged the formation of a national dialogue, Robert Cooper, E.U.’s foreign policy adviser defended repression against protestors, noting that “accidents happen” (Phillips 2011).

Regime survival in Bahrain is entwined with, and predicated on, balance of power considerations for regional and international states seeking to curb Iranian influence in the Persian Gulf to maintain access to one of the world’s most valuable oil transit route. Thus, foreign military intervention in Bahrain by allied GCC states ensured the regime’s survival given its unique demographic composition as the only Shia majority states in the GCC with a history of domestic unrest and foreign influence from GCC states and Iran.

Libya’s failed humanitarian intervention

Localized uprisings across Libya in 2011 produced a window of opportunity for regional and international actors to alter the balance of power in favor of anti-Qaddafi forces for the purpose of eliminating a longstanding adversary. Although external actors were unified in pursuing regime change, divergent ideational and material interests fueled competition between regional and international actors, producing a highly bifurcated transition and internationalized civil war. Qaddafi’s support for terrorism made his ouster a priority for Western powers, particularly the USA, UK and France. Following Qaddafi’s violent crackdown on mass protestors in Benghazi in February 2011, the Arab League’s 22-member body requested the creation of a no-fly zone from the U.N. Security Council (UNSC) to protect civilians from government attacks on March 12, 2011 (Al (Jazeera 2011). On March 17, 2011, the UNSC adopted Resolution 1973 invoking the “responsibility to protect” civilians and authorized the use of force following the implementation of a no-fly zone and an arms embargo in early 2011 (United Nations Security Council 2011). The NATO coalition supported rebel groups on the ground through coordinated attacks on Qaddafi’s 75 person convoy fleeing to Sirte, which killed an estimated 25 loyalists while injuring Qaddafi (Gazzini 2011). British and Qatari special forces on the ground provided crucial logistical and tactical support for rebel commanders to encircle Qaddafi remaining convoy in Sirte, leading to his capture and murder by rebel groups supported by international and regional actors under NATO’s command (Ibid). American-led NATO airstrikes, France’s recognition of rebels groups as Libya’s transitional government and direct military support from regional states to rebel factions bolstered rebel capabilities. Logistical and military support for anti-Qaddafi rebel forces thus titled the balance of power in favor of anti-regime rebel factions, resulting in foreign-imposed regime.

Western strategic interests in Libya predate the 2011 intervention. Qaddafi’s attempts to pivot the international balance of power to the third world made Libya a sight of strategic competition during the Cold War (Anderson 1982, 532). His subsequent support for extremist Islamist groups and Libya’s role in the bombing of Pan AM Flight 103 in 1988 posed a threat to regional and international security. External pressure and sanctions by western states in the 1990s and the rising threat Islamist groups such as the Libyan Islamic Fighting Group (LIFG) posed for Qaddafi led to regime reproachment with the United States in 2003. By 2006, the Bush administration formalized full diplomatic relations with Libya after it accepted responsibility for the Pan Am bombing and agreed to halt its weapons of mass destruction and long-range missiles program (Blanchard 2010). Within the context of the post 9/11 era, the USA committed limited funds for non-proliferation and counter-terrorism initiatives and strategic cooperation against the LIFG and al-Qaeda in the Islamic Maghreb (Ibid, 10). However, Qaddafi remained an unpredictable leader for western states, with a longstanding record of human rights abuses against civilians and dissident groups. Growing fears of mass repression of pro-democracy protestors in eastern Libya led to President Obama’s commitment to the U.N.-sanctioned NATO intervention. Diplomatically, Obama’s decision mollified British, French and Arab Gulf interests to bolster military and logistical capabilities against Qaddafi’s forces (Obama 2020) 652). Since 2011, the United States has selectively engaged in strategic operations in Libya to contain emergent security threats, including the Battle for Sirte in 2016 against the Islamic State through Operation Odyssey Lightening.

Qaddafi’s reproachment facilitated diplomatic, political and strategic cooperation between western European powers in the areas of oil exports, anti-terrorism and migration controls. In particular, the market potential for British, French and Italian arms manufactures created competition and an exponential growth of military equipment sales to Libya after the E.U. lifted its arms embargo in 2004 (Hansen and Marsh 2014, 281–282). However, Qaddafi’s conditional strategic cooperation with western powers, repression of dissidents and his longstanding history of anti-western policies made him an unpredictable figure. The uprisings provided an opportunity for western European powers, particularly the UK and France, to alter the balance of power in North Africa against a longstanding adversary while attempting to restore their prestige and great power status (Dawson 2021; Davidson 2013). Prime Minister David Cameron saw an opportunity in Libya to exert the long declining power of the UK by ensuring that Britain remained at the forefront in responding to a failed pariah state “on Europe’s southern border, potentially threatening our security, pushing people across the Mediterranean and creating a more dangerous and uncertain world for Britain and for all our allies as well as for the people of Libya” (UK Foreign and Commonwealth Office 2011). On a strategic level, Britain’s ability to tilt the balance of power in favor of anti-Qaddafi rebel forces ensured that Libya would not return to supporting terrorism while bolstering the security of maritime trade routes and shipping lanes in the Mediterranean, all of which are vital to its national interests (Cristiani 2014, 6).

France’s early decision to spearhead international regime change efforts, its lobbying for EU and international sanctions, a U.N. administered no-fly zone, and its coordination with Arab states regarding the use of force, made it the leading advocate for international intervention in Libya (Davidson 2013, 317–318). President Sarkozy’s push for regime change and his support for rebel groups in the south early 2011 through covert shipments of rocket launchers, assault rifles, machine guns and Milan anti-tank missiles transformed anti-Qaddafi rebel capabilities (Gélie 2011). France’s support for rebels groups in eastern Libya alongside Egypt, Saudi Arabia, the UAE and Russia sought to balance against Qatar and Turkey’s backing of the Islamist-dominated government in Tripoli. President Marcon’s support of General Haftar’s military campaigns was predicated on the idea that a strongman solution will bring unity and order to Libya, contain the rise of Islamist groups and help France’s Total secure oil contracts from Haftar-controlled eastern regions (Taylor 2019). Oil, migration and terrorism undergird France’s geostrategic interests in Libya as it balances against competition from Italy, Turkey and Russia. Although Italy’s energy company ENI has the largest influence in Libya’s oil production and exports, France has attempted to secure stakes in Libya’s oil production for its energy company, Total. In 2019, Libya’s National Oil Corporation (NOC) approved Total’s $450 million purchase of 16.33 percent minority stake in the Waha oil field concessions, one of the largest oil fields in Libya (Reuters 2019). To curtail the growing influence of the Islamist-dominated Libya Dawn coalition supported by Qatar, Turkey and Sudan, France joined forces with the UAE, Egypt, Jordan and Saudi Arabia in providing military support for anti-Islamist forces under the Libyan National Army led by General Haftar through Operation Dignity (Wehrey 2020, 8).

Although Italy initially expressed reservations about regime change given its commercial and security partnerships with the Qaddafi regime, it agreed to join the NATO coalition only after it guaranteed assurances from rebel leaders to honor Qaddafi-era agreements pertaining to access to oil and gas exports and curbing migration (Lombardi 2012). Italy’s strategic interests in Libya are predicated on maintaining access to the country’s oil and gas reserves considering that Italy is Libya’s largest oil importer and its only gas export destination (Elliott 2020). In 2017, Italy signed a controversial Memorandum of Understanding with the GNA and Tripolitanian allied proxies to provide financial and military support to the Libyan Coast Guard. While the MoU has significantly halted the flow of migration across the Mediterranean, it has led to systematic human rights violations against migrants in Libya (Human Rights Watch 2020). Italy pursued strategic stability by bolstering the capabilities of the internationally recognized Government of National Accord (GNA) in Tripoli to maintain its geostrategic interests and balance against France and Gulf states’ support for Qaddafi-era general, Haftar.

Although Russia abstained from UNSC Resolution 1973, it supported a no-fly zone in Libya. Russia’s geostrategic interests, akin to those in Syria, are predicated on establishing military, economic and political influence in the Middle East and the Mediterranean to balance against Turkey’s growing influence and compete against western powers. Russia joined forces with the UAE, France, Egypt, Jordan and Saudi Arabia in 2014 by backing General Haftar and allied militias in their attempt to take over the GNA in Tripoli. Russia provided an estimated 1000 paramilitary fighters through the Wagner Group and mercenaries to fight alongside Haftar’s forces in eastern Libya and coordinated efforts with Egypt and the UAE to provide technical, logistical and financial support by printing currency through the illegitimate Central Bank in eastern Libya to bolster Haftar’s capabilities against the GNA (Wehrey 2020, 7, 21–22). As noted by Wehrey, Russian assertiveness in Libya since the uprising has been opportunistic: seeking to maintain energy control and arms and infrastructure deals while balancing against Turkey and western European states partially facilitated by America’s declining influence in Libya (Ibid, 21). Russia’s intervention is predicated on altering the balance of power away from western and American influence to secure and maintain its economic, diplomatic and military interests in the MENA.

Qaddafi’s ouster in 2011 provided a window of opportunity for regional states to exert influence by backing competing political groups and militant rebel factions. Regional intervention has been largely bifurcated along those supporting the Islamist-dominated government in Tripoli against anti-GNA factions in eastern Libya. Regional actors—primarily Qatar, the UAE, Egypt, Jordan and Saudi Arabia, were united in advocating for regime change, albeit with contrasting motivations. Whereas Qaddafi’s disdain for Gulf sheikhdoms galvanized their support for regime change and provided regional legitimation for the intervention (Engelbrekt et al. 2014, 6), Turkey supported the intervention after it ensured that preexisting economic and financial contracts in Libya would be safeguarded.

Turkey and Qatar supported the internationally recognized GNA in Tripoli and its allied Islamist groups, particularly those with ties to the Muslim Brotherhood. During the initial uprising, Qatar provided an estimated $400 million to various Islamist rebel groups, including the 14 February Martyrs Brigade, and supplied them with large amounts of weapons and training, including Milan anti-tank missiles and infantry training by Qatari special forces, making the Gulf emirate “a link between rebels and NATO forces” (Black 2011). While Qatar’s support for Islamists fulfilled an ideational objective, Doha’s backing of Islamist groups rested on its assessment of them being cohesive and militarily capable with deep commitments to remaking the post-Qaddafi order (Wehrey 2020, 13–14). The uprisings in Libya provided Qatar an opportunity to exert small-state soft-power influence through personal connections to Qaddafi dissident groups to balance against regional rivals often in support of Muslim Brotherhood-aligned dissident groups (Ulrichsen 2014, 126–127).

Turkey’s initial opposition to regime change was based on the lack of domestic support for the intervention among Turkish public opinion, safeguard Turkish infrastructure investments and Turkish expatriates working in Libya, and its fractious alliance with France at the time due to Sarkozy’s opposition to Turkey’s accession into the E.U. (Chivvis 2014, 73). Turkey aligned closely with the US position when it became clear that an intervention was imminent by March 2011. Since 2011, Turkey has bolstered the bargaining power of Islamist factions in Tripoli while safeguarding $18 billion worth of construction and investment projects to maintain its leverage over access to oil and gas reserves in the Mediterranean (Hacaoglu 2019). Turkey’s assertive foreign policy under Erdogan, particularly its support for Islamist-aligned factions in Libya and Syria, undergirds its ideational and material support for the Islamist-dominated GNA in Tripoli following Qaddafi’s ouster. To maintain its geostrategic interests in Libya and cement its foothold in North Africa and the Eastern Mediterranean, Turkey and the GNA signed a maritime demarcation and military agreement in November 2019. Turkey aided the GNA in their final offensive to expel Haftar’s forces from northwestern Libya in June 2020, which severely degraded Haftar’s capabilities. Turkey’s preference for a unified and stable Libya is predicated on maintaining long-term strategic goals by expanding its sphere of influence in the Eastern Mediterranean, maintaining longstanding commercial interests, particularly in the energy sector, and potential access to markets in the Sahel and the rest of Africa for Turkish construction companies and export-oriented manufacturers (Harchaoui 2020, 6–7).

To counter Qatari and Turkish influence, the UAE, Saudi Arabia and Egypt lent support for Qaddafi-era General Haftar against the internationally recognized government in Tripoli to contain Islamists and maintain strategic access to the Mediterranean. Initially, Egypt intervened to contain the flow of migration from eastern Libya at the onset of the conflict in 2011. Since 2014, Egypt under President al-Sisi has provided military and logistical support for Emirati and Saudi efforts to quell the rise of Muslim Brotherhood-aligned Islamist factions of the GNA. Egypt signaled the desire to support U.N.-backed reunification efforts following the inauguration of a large naval base 135 km from its border with Libya (Lewis 2021).

Although the UAE sought to tilt the balance of power against Islamists in Tripoli backed by Qatar and Turkey, it too attempted to secure access to strategic waterways in the eastern Mediterranean and maintain a foothold in North Africa and the Sahel. While Arab Gulf leveraged influence with anti-GNA rebel groups headed by General Haftar in Libya’s oil-rich eastern provinces, the UAE became the largest broker and supplier of military and logistical support for operations in eastern Libya. Between 2014 and 2017, the UAE provided military and strategic aid, including military hardware, for Haftar’s forces in eastern Libya from the al-Khadim airbase, located about 105 km from Benghazi (Lewis 2017). Qatar and the UAE attempted to alter the balance of power by supporting rival Libyan exiles in 2011 to secure distinct geostrategic spheres of influence, which contributed to the fractionalization and militarization of the post-Qaddafi transition (Wehrey 2020, 14–16).

Foreign military intervention in Libya set the path for persistent meddling by regional and international actors. The NATO-led intervention opened a window of opportunity for external actors to alter the balance of power and articulate competing geostrategic interests following Qaddafi’s ouster and accelerated the proliferation of rebel groups, producing a security vacuum sustained by arms imports to warring rebel groups backed by regional and international actors. Libya became an arena of strategic competition between regional and international rivals with Turkey, Qatar, Italy and the United States providing military, economic and political support for the internationally recognized government in Tripoli and France, Egypt, Saudi Arabia, the UAE and Russia maintaining a strategic alliance in support of General Haftar and allied militias in eastern Libya. Consequently, Libya descended into a proxy “war of the many” (Badi 2019). The discovery of vast continental gas shelves in the eastern Mediterranean has fueled foreign meddling in Libya as regional and international actors balance against emerging strategic interests (The (The The The Economist 2020). By late 2020, the U.N. Acting Special Envoy for Libya concluded that the presence of 10 military bases and 20,000 foreign fighters either fully or partially occupied by foreign forces in violation of the U.N. arms embargo poses a “serious crisis”, noting that “They are not in Libya for your interests, they are in Libya for their interests” (United Nations Support Mission for Libya 2020).

Syria as an arena of regional and international competition

The 2011 uprisings in Syria altered state capabilities and opened a window of opportunity for regional and international actors to pursue militaristic interventions both in support of the Assad regime and competing rebel factions. External intervention in the Syrian uprising produced an internationalized and protracted civil war sustained by support for proxy rebel groups (Byman 2018). The initial anti-Assad axis formed between the Gulf States and Turkey attempted to balance against the capabilities of Iran and its proxies, Hezbollah and Hamas (Hassan 2013). Israel has attempted to tilt the balance of power against the Syrian regime by arming as many as 12 anti-Assad rebel groups in southern Syria through military transfers of assault rifles, machine guns, mortar launchers and transport vehicles to prevent Iran-backed groups and IS militants from advancing near the Israeli border (Tsurkov 2018). Thus, regional and international actors sought to alter the balance of power in pursuit of competing ideational and material interests at the onset of largely peaceful pro-democracy protests in 2011.

Turkey seeks to maintain ideational and material interests and balance against emerging security threats along Syria’s northeast border (Kösebalaban 2020). The expansion of Turkey’s securitization zone into northeast Syria aims to obstruct the rise of Kurdish separatism and consolidation of political and militant organizations such as the Kurdish-led Syrian Democratic Forces and the Kurdish Democratic Union Party (YPD) and its militia, the People’s Protection Units (YPG)-an offshoot of the Kurdistan Worker’s Party (PKK). Growing sectarian polarization across the region pivoted Turkey toward Gulf persistence on regime change in Syria (Haas et al. 2013, 162–163). Dubbed a “jihadist highway” (Uslu 2016, 784), Turkey helped form the Free Syrian Army, armed Islamist rebels, and became a conduit for their entry into Syria (Pamuk and Tattersall 2015). The containment of the PKK and its offshoot, the YPG, has entrenched Turkey’s intervention as evinced by Operation Olive Branch of January 2018 in Syria’s Afrin district. As an alliance between Turkish forces, Turkmen militias and Turkish-backed Free Syrian Army rebels, the Operation rearmed jihadist Islamists and Syrian rebels (Al-Khalidi 2018).

Similarly, Gulf states sought to alter the balance of power by supporting anti-Assad rebel factions. Although Bashar al-Assad sectarianized the uprisings to denigrate protests in largely Sunni areas, support for anti-Assad rebels by Arab Gulf states similarly fractionalized the Syrian opposition by empowering radical Sunni Islamist groups such as Jabhat al-Nusra and the Salafist Islamic Front (Phillips 2015, 369–370). Saudi Arabia provided infantry weapons, financial support and training of Islamist groups such as the Army of Islam and the Army of Muhammad (Chivers and Schmitt 2013). Likewise, Qatar aided Islamist Syrian rebel groups with an estimated $1–3 billion, which included an estimated 70 military cargo flights via Turkey from April 2012 to March 2013 and two shipments of shoulder-fired missiles, including Chinese-made FN-6s, through Turkey (Khalaf and Smith 2013; Mazzetti et al. 2013). Arab Gulf states attempted to balance against Iran’s influence in Syria through private and government funding for warring Islamist factions (Dickinson 2013). Financial support for anti-Assad and anti-Iranian Islamist groups posed a strategic challenge for the USA and its Western allies. In a leaked email to senior advisor John Podesta, then Secretary of State Hilary Clinton noted that in addition to the reliance on more covert military operations, the USA must “use our diplomatic and more traditional intelligence assets to bring pressure on the governments of Qatar and Saudi Arabia, which are providing clandestine financial and logistic support to ISIL and other radical Sunni groups in the region” (Wikileaks 2014). Material support for rebel groups enabled Gulf states to leverage substantial influence in the 2011 uprising in hopes of altering the balance of power in favor of regime change.

Iranian intervention in Syria is predicated on maintaining the balance of power in favor of the Assad regime against external meddling by Arab Gulf states and Turkey. The convergence of the Iran-Syria alliance axis since 1979 is rooted in shared systemic anti-imperial grievances, resistance to foreign and western hegemony and meddling in the region, the Iran-Iraq war and Egypt’s peace with Israel following the signing of the Camp David Accords (Ehteshami and Hinnebusch 1997, 90–93). To maintain influence, Iran has exploited religious symbolism and sectarian kinship ties to legitimize its alliance with, and defense of, Bashar al-Assad’s Alawite identity through venerated Shia sites such as the shrines of Sayda Zaynab and Sayda Ruqaya, the Shrine of Husayn’s head in the Umayyad Mosque in Damascus, the Mashhad al-Husayn in Aleppo and the mausoleum of “Ammar bin Yasir, Uways al-Qarani, and Ubay bin Ka’b in Raqqa” (Pinto 2007, 110). The deployment of religious and sectarian symbolism reifies the importance of these site as powerful recruiting tool for Shia militias from neighboring Iraq and Lebanon to maintain the geopolitical nexus that binds the alliance between the two countries and their proxies. As Matthiesen notes, this reflects a tactical and strategic attempt by Iran to secure its interests through militant religious proxies (Matthiesen 2013). On a material level, Iran has helped the Syrian regime sustain economic shocks induced by the civil war with $16 billion of financial and economic aid since 2012, including three liens of credit totaling over $6.6 billion since 2013 (Hatahet 2019). Stabilizing the Syrian regime opens a potential market for Iranian exports amid stifling international sanctions particularly given that financial aid prioritizes lines of credit for Iranian companies operating in Syria (Ibid). The strategic alliance between the regional “odd couple” (Ehteshami and Hinnebusch 1997, 87) has enabled both Damascus and Tehran to balance against regional and international threats.

Russia’s backing of the Syrian regime reflects historic and contemporary relations between the two countries to alter the balance and distribution of power against Western influence in the region. On October 8, 1980, the Soviet Union signed a Treaty of Friendship with Syria aimed at strengthening political, economic, military, scientific, technological, cultural ties and respect for state sovereignty, national independence and the principles of non-interference and the “elimination from the practice of international relations of any manifestations of the policy of hegemonism and aggression” (Survival. 1980). Given this history between the two nations, Russia, backed by China, vetoed U.N. Security Council resolutions invoking humanitarian intervention over the use of chemical weapons. Domestically and regionally, Russia’s struggle with radical Islamist groups in the North Caucasus region reached its zenith with the declaration of the Caucasus Emirate, a jihadist organization of mostly ethnic Chechens in 2007, and their subsequent allegiance to the Islamic State in 2015, which pinned Russia in direct conflict with the Islamic State in Syria (International Crisis Group 2016). Whereas the bulk of foreign jihadists inside Syria came from Tunisia, an estimated 5000–7000 nationals from Russia and former Soviet territories constituted the largest cluster of jihadists from outside the region. By 2015, around 2400 of foreign jihadists in Syria were Russian nationals, a jump from 800 in 2014 (The Soufan Group 2015).

Since 2011, Russian foreign aid to Syria is driven by the need to expand its power and capabilities in the region. Russian backing of Bashar al-Assad has entrenched its financial and economic access to Syrian markets for Russian firms. These include reconstruction concessions, oil and gas investments for private and state-owned firms, and a fifty-year contract to mine phosphate at the Sharqiyeh field near Palmyra with 30% of revenues reserved for the Syrian state (Hatahet 2019). Russia has also become a key contender in Syria’s agricultural sector through control of strategic crop fields, making it the leading supplier of wheat (reaching an estimated 1.5 million tons in 2018 (Ibid). Strategically, although limited in capacity, Russia has announced an expansion of its sole naval based in the Mediterranean located in Tartus, Syria. Built in 1971, the base is limited in scope and capacity. The new expansion follows the signing of a 49-year lease agreement between Syria and Russia to revamp and expand the base, upgrade its tactical and logistical capabilities and enhance Russia access and influence in the Middle East, North Africa and Europe (Ibid).

Prevented from toppling Assad through an internationally sanctioned intervention, Western states sought to alter the balance of power in favor of anti-Assad rebel factions. In 2011, the E.U. suspend Syria’s membership in the Euro-Mediterranean Partnership and imposed targeted economic and diplomatic sanctions by freezing the assets of Syrian individuals and companies, halted Syrian oil imports and economic investments in the country (European Commission 2019). Most E.U. member states joined Operation Inherent Resolve in 2014 to neutralize ISIL in Iraq and Syria. France’s Sarkozy became the first international leader calling for Assad’s ouster in 2011, advocating a Libya style intervention for the purpose of regime change. Both Hollande and Macron pursued an active foreign policy to tackle ISIL and limit Assad’s capabilities, with Hollande admitting to arming Syrian rebels in 2014 to neutralize both targets (Olivas-Leal 2014). Britain joined western states in condemning Assad’s use of chemical weapons. As part of Operation Inherent Resolve, the UK has committed resources and manpower through the RAF’s Operation Shader, which, since 2014, has targeted ISIL fighters in Iraq and Syria, killing an estimated 4000 members (Kearney 2019). At the backdrop of American drawback from Syria, the Trump Administration struck a deal with France and the UK to maintain and increase troop deployments by an additional 10–15 percent with American funding (Selgiman 2019).

Syria’s reliance on Iran, its ideological support for Hezbollah, Hamas and Iran-backed militias in Iraq post-2003 underscore its geopolitical significance for the USA (Wikileaks. 2008). The Syrian uprising opened a window of opportunity for the USA to intervene militarily, financially and logistically to alter the distribution of power in favor of anti-regime forces. Dissuaded from intervening unilaterally, the Obama administration’s “no boots on the ground” strategy prioritized covert interventions through the use of drones, multilateral engagement with regional allies and support for allied rebel factions (Calhon 2018). This was reflected in a memo by then Secretary of State Hilary Clinton with respect to American strategy for combating ISIL which advocated for providing “the FAS, or some moderate forces, with equipment that will allow them to deal with a weakened ISIL and stopped up operations against the Syrian regime. This entire effort should be done with a low profile, avoiding the massive traditional military operations that are at best temporary solutions” (Wikileaks 2014).

American reliance on covert military operations to weaken the Assad regime by supporting the Free Syrian Army (FSA) and competing Islamist rebel factions bolstered the power of warring rebel groups and fractionalized the Syrian opposition. The CIA launched Operation Timber Sycamore in 2013 as an attempt to covertly provoke regime change by tilting the balance of power to domestic anti-Assad rebel forces. Costing an estimated $1 billion, the Operation, initially proposed by then CIA Director David H. Petraeus in 2012 with resolute lobbying from Jordan, Israel and Saudi Arabia, trained rebels in Jordan and Turkey and provided weapons to FSA fighters vetted by the CIA (Mazzetti et al. 2013). Although the USA remained a key funding source for the program, Saudi Arabia contributed large sums of cash and weapons (Mazzetti and Apuzzo 2016). In addition to the CIA program, the Pentagon launched a $500 million program to train and equip 5000 anti-Assad Syrian rebels in 2014 in response to ISIL’s advancement. The Pentagon halted the costly program aimed at creating “capable, indigenous forces” in 2016 after it produced only a handful of fighters (5–7 by some estimates) due to rebel desertions (Shear et al. 2015). To supplement the failure of the train and equip program and with ISIL posing an increasing threat to domestic, regional and international security, the Pentagon pursued a $2.2 billion Syrian rebel covert program that funneled Soviet-era weapons, including, AK-47s, rocket-propelled grenade launchers, mortars, to Syrian Democratic Forces (SDF) comprised mostly of Kurdish YPG forces working alongside Arab and Assyrian militias in the Jazira region of northeast Syria (Angelovski and Marzouk 2017). The weapons were purchased by the Special Operations Command (SOCOM) from Central and Eastern European states and transferred by air and sea to Turkey, Jordan and Kuwait and were distributed to anti-Assad rebel forces through the Black Sea Route in northern and southern Syria (Angelovski and Marzouk 2017).

External actors intervened in the Syrian uprising to alter the balance of power in favor of pro and anti-Assad forces in pursuit of competing ideational and material interests. Multi-sided foreign military interventions produced an internationalized civil war and created conditions ripe for proxy warfare between warring rebel forces seeking to gain territorial control to influence the initial uprising’s trajectory (Rosenblatt and Kilcullen 2019). The conflict also created a diplomatic rift between traditional NATO allies Turkey and the USA as the former seeks to eradicate the most viable American ally of the FSA, the YPG, due to its affiliation with the Kurdistan Workers Party (PKK)—a designated terrorist organization in Turkey. As in Libya, multi-sided interventions produced an internationalized civil war that exacerbated the militarization of the Syrian uprising and contributed to the cooptation, fractionalization and sectarianization of the 2011 pro-democracy protest movement.

External intervention and Yemen’s fractured transition

Yemen’s post-Arab Spring transition has been dictated in large part by external actors seeking alter the balance of power to maintain distinct spheres of influence. Regional influence, particularly of Gulf states, in Yemen’s transition solidifies their position as “emerging interventionists” seeking to augment domestic unrest in pursuit of geopolitical security amid an increasingly dynamic-and tumultuous regional environment (Young 2015, 10). The GCC-initiated transition plan for Yemen maintained the ruling party’s core ruling elite and replaced the GCC-allied president Ali Abdullah Saleh with his vice president “Abd Rabbu Mansur Hadi” on November 23, 2011. The U.N. transitional plan became a battleground for foreign influence as states sought to alter the balance of power by supporting allied political factions. Whereas Qatar and Turkey backed Sunni Islamist groups tied to the MB, Iran provided limited support for the Houthis, and Gulf states, most notably Saudi Arabia and the UAE, provided political and financial support for General Hadi and the General People’s Congress part (Baron 2019). The failure of the 2013 National Dialogue conference to produce a sustainable political solution to Yemen’s post-2011 transition, the growing threat from al-Qaeda in the Arabian Peninsula (AQAP) and Houthi takeover of the capital Sanaa and the strategic Port of Hodeidah (Yemen’s largest port) and their expansion into southern Yemen and the Arabian Peninsula by 2014, incentivized regional meddling with assistance from western states.

In 2015, Saudi Arabia launched Operation Decisive Storm—an international coalition against Houthi rebels back by the UAE, the USA, UK and France “to protect the people of Yemen and its legitimate government from a takeover by the Houthis. A Violent extremist militia” (Embassy of the King of Saudi Arabia 2015). Saudi Arabia attempted to alter the balance of power by curbing geostrategic threats emanating from Iranian support for Houthi militias forces “with ambitions and projects of sabotage in Arab countries” (Al-Arabia 2015). In 2018, a top Coalition general reiterated Saudi Arabia’s position that the Houthis were funded by Iran and Hezbollah (Saudi Press Agency 2018). Saudi Arabia’s support for Saleh-era Field Marshall Hadi reaffirmed historic relations between the Kingdom and the two Yemeni leaders who often relied on Saudi intervention to quell Houthi rebellions prior to 2011 (Baron 2019). The UAE has been a keen supporter of the Southern Transitional Council (STC)—a separatist movement seeking to reverse Yemen’s 1990 unification whose leaders profess kinship ties with the UAE due to shared cultural and religious relations (Ibid, 7). The Yemeni uprising provided a window of opportunity for Arab Gulf states to balance against Iranian proxies while simultaneously pursuing competing ideational and material interests in the Arabian Peninsula.

Western support for the Saudi-led coalition from the USA, UK and France included arms sales, costly refueling missions and logistical support from US Central Command and US Africa Command (Gould 2019). Moreover, the USA and UK remained key weapons suppliers for Saudi Arabia and the UAE. According to SIPRI data, from 2015–2017, arms exports to Saudi Arabia from the USA reached $6.9 billion and exports from the UK to Saudi Arabia totaled over $2 billion. Similarly, arms exports to the UAE from the USA totaled over $2 billion, while the UK sold over £7 billion worth of weapons and dual-use equipment to Saudi Arabia between 2008 and 2017, with purchases spiking post-2015 (Action on Armed Violence 2018). Weapons sales to Saudi Arabia, while congruent with the history of American foreign policy toward the Kingdom,Footnote 4 directly contributed to Yemen’s civil war and humanitarian catastrophe since 2015. France’s military intelligence acknowledged that French weapons sold to Saudi Arabia and the UAE have been used in Yemen, contradicting earlier assurances from President Macron that such arms sales were strictly for defense purposes (Dodman 2019). By supporting various anti-Houthi elements, the UAE and Saudi Arabia leveraged historic ties with various Yemeni factions to alter the balance of power against potential Iranian expansionism in the Arabian Peninsula. Although the UAE formally withdrew from Operation Decisive Storm in July 2019, recent evidence suggested it has recalibrated and entrenched its interests and capabilities by building an airbase on the strategic Island of Mayun located in the Bab el-Mandeb Strait-a a key global oil chokepoint (Riedel 2021).

Iranian influence in Yemen, and especially among the Houthis, has historically been marginal. Contradicting the Yemeni government’s claims that Iran had been arming the Houthis, US Ambassador to Yemen Stephen Seche in 2007 noted that evidence points to the Houthis obtaining their weapons from the Yemeni black market and the government itself rather than Iran or its proxies (Wikileaks 2009). Although Iran’s objectives in Yemen and its support for the Houthis post-2011 are limited on both material and ideational grounds (Juneau 2016), instability following Saleh’s ouster enabled Iran to strike a limited alliance with Houthis in an attempt to alter its distribution of power in relation to Saudi and Emirati influence. Similar to its engagement in Syria, Iran’s support for the Houthis is a continuation of its ideational and strategic axis of alliances with non-state actors in the region including Hezbollah, its allies in Syria, and Iraq’s Popular Mobilization Forces. Given the opportunity to exert influence in Yemen’s domestic affairs to balance against Saudi influence, Iran’s interests in Yemen and its incipient support for Houthi shifted toward bolstering its coercive capabilities by supplying the group with advanced weaponry, aiding the group’s control of key territories and shipping ports, and undermining disarmament efforts by disregarding the international arms embargo created under UNSC Resolution 2216 of 2015. However, whereas Iran’s deployment of sectarianism served as a mobilizing tool in Iraq, Bahrain and Syria, its ideational sway among the Houthis has been inflated by Iran and regional rivals to justify competing intervention narratives (Cafiero and Krieg 2019).

Russia’s interest in Yemen predates the 2011 uprisings as the external patron of the Soviet-leaning Marxist–Leninist state of the People’s Democratic Republic of Yemen (PDRY) prior to Yemen’s unification in 1990. Russian support for the PDRY was predicated on maintaining access to the strategic port of Aden to ensure the free flow of oil and secure its access to states in the Red Sea (Mahmood 2019). To counter western influence in Yemen, Russian abstained from UNSC Resolution 2216 of 2015 and vetoed a 2018 U.N. Security Council resolution castigating Iran’s non-compliance with the arms embargo stipulated in Resolution 2216.

Although Saleh’s ouster led to a relatively smoother transition in its immediate aftermath, the geopolitical and geostrategic interests of international and regional powers subverted democratization prospects. External actors attempted to bolster the capabilities of competing political factions in Yemen in an attempt to alter the balance of power to maintain distinct geostrategic spheres of influence.

Conclusion

This article has offered a structural explanation of military interventions in a subset of Arab Spring cases to explain the exponential rise in, and simultaneity of, foreign military interventions following region-wide protests in Bahrain, Libya, Syria and Yemen. I have argued that the simultaneity of mass uprisings within a given temporal setting produced a strategically permissive regional environment and provided the opportunity structure for regional and international actors to pursue competing material and ideational interests during the region’s largest pro-democracy wave. In doing so, foreign actors sought to alter the balance of power by leveraging distinct spheres of influence manifested by support for ruling autocrats and/or warring rebel factions.

Through a comparative analysis of countries that experienced mass protests followed by foreign military interventions, I have illustrated the argument that on a regional level, the uprisings provided a window of opportunity for external actors to pursue competing ideational and material interests to create, maintain or augment geostrategic spheres of influence. Through a multilayered analysis that captures regional and international interventions, I show how and why interest and opportunity shaped the pursuit of militaristic foreign policy decisions to alter the balance of power in a permissive regional environment. States that endured multi-sided competitive interventions in support of both ruling autocrats and warring rebel factions, as in Libya, Syria and Yemen, produced more violent trajectories marked by prolonged and internationalized civil wars. On the other hand, the limited but decisive military intervention in Bahrain succeeded in protecting the ruling monarchy against domestic threats. I argue this is largely predicated on the degree of threat domestic ruptures pose for intervening states, which determine conflict duration and complexity. Thus, the level and scope of interventions varied given that states sought to alter the balance of power in a competitive regional environment.

External interventions in the Arab uprisings offer three important insights for analyzing how a change in a region’s structural composition can induce external interventions by states pursuing competing interests. First, the uprisings illustrate how timing and sequencing of region-wide mass protests created a window of opportunity that made states more vulnerable to external intervention. Second, the exponential increase in foreign military interventions preceding conflict during initial protests illustrates how structural drivers of insecurity shaped external actors’ calculous to intervene militarily for the purpose of securing distinct ideational and material interests. Lastly, by offering a structural explanation of foreign military interventions, I have demonstrated the ways in which international interactions shape domestic outcomes in states experiencing political ruptures. Doing so pivots existing explanations of divergent outcomes of the Arab Spring away from domestic factors to illuminate the effects of the external environment on subsequent conflict duration and escalation.