Non-State-Led Proxy Warfare:
The Missing Link in the Proxy Wars Debate
By Tarik Solmaz
Conflicts in the early 21st-century have been dominated by proxy wars. In parallel with the dominance of the strategy of war by proxy in contemporary armed conflicts, the academic literature on proxy warfare has rapidly proliferated over the last two decades. Nevertheless, existing understandings of proxy warfare seem a bit problematic. Most scholars have considered proxy warfare as a way of warfare exclusively employed by states, in particular, global powers and regional actors. However, non-traditional forms of proxy warfare do exist, and today we have witnessed non-state actors raising and training their own proxies. So, this paper argues that it is time to think about non-state-led proxy warfare.
Let us continue by asking the so what question: Why should we think about non-state-led proxy warfare? Traditionally, in both theory and practice, non-state armed groups have mainly been associated with terrorism and/or insurgency warfare. As such, states have primarily aimed at eliminating non-state threats through counterterrorism and/or counter-insurgency tactics, techniques, and procedures. However, non-state-led proxy warfare shows that currently, violent non-state actors can employ sophisticated ‘political warfare’ capabilities. Briefly speaking, the term ‘political warfare’ means the employment of one or more elements of national power short of war to reach political objectives. That is, the concept of ‘political warfare’ essentially reflects an ancient idea of breaking the enemy's resistance without fighting. In practice, ‘political warfare’ can take many forms, and proxy warfare represents one of the most effective forms of it. By definition, ‘political warfare’ has traditionally been associated with states. Nevertheless, as a RAND report has recently identified, today “[n]onstate actors can conduct political warfare with unprecedented reach.” This paper argues that non-state-led proxy warfare, which exemplifies a form of non-state ‘political warfare’ after all, reveals that non-state actor can attain their political objectives without carrying out terrorist or guerilla-style attacks. Therefore, states may need to revise their existing strategies used to negate non-state threats.
The main purpose of this article is to explore some patterns regarding non-state-led proxy warfare, and so, to find out whether, and if so, how it differs from state-led proxy warfare. For these purposes, this article uses two case studies: al-Qaeda’s sponsorship of the Caucasus Emirate and Hezbollah’s support of Yemeni Houthis.
So far, only a few talked of non-state sponsorship. While some have only superficially touched on the topic, others have compared state-led and non-state-led proxy warfare and concluded that the former is notably different from the latter. However, this article will attempt to argue that the similarities between state-led and non-state-led proxy warfare outweigh the differences.
As noted earlier, the existing literature on proxy warfare is predominantly state-centric. To our best knowledge, Andrew Mumford is the first author who argues that proxy warfare is not a form of warfare carried out solely by state actors. Accordingly, he points out that non-state actors can use a state or another non-state group as a proxy force. For Mumford, al-Qaeda’s support for Lashkar-e-Taiba represents an example of proxy warfare conducted by a non-state actor. Admittedly, Mumford's ideas on non-state-led proxy warfare are ground-breaking given that the proxy warfare literature has merely focused on state-led proxy warfare at the time. However, in his work, he has analyzed neither the non-state sponsorship nor the al-Qaeda case itself systematically, and thus, he has not really addressed if any difference between state-led and non-state-led proxy warfare exists. Therefore, as some scholars have indicated, Mumford’s assessments regarding the subject remain substantially theoretical.
Candace Rondeaux and David Sterman have criticized the state-centrism in the literature on proxy warfare, and have maintained that in today’s proxy wars, non-state actors can be both sponsor and proxy. In the words of Rondeaux and Sterman:
Hezbollah, while acting in part as a surrogate of Iran, has placed itself at the center of a large network of non-state groups engaged in conflict across the Middle East, providing training to the Houthis in Yemen and support to pro-regime forces in Syria… [A]l-Qaeda worked through front groups and coalitions rather than engaging in direct efforts to seize territory and exercise governance itself... This strategy echoes al-Qaeda’s origins as an organization based around providing training and financing to independent groups and individuals— in essence, a proxy strategy of terrorism.
Recently, several scholars have talked of the role of non-state sponsors in the Syrian Civil War. For example, comparing the impacts of state and non-state sponsorship on proxies, Christopher Phillips and Morten Valbjørn, who focus on the Islamic State in Iraq’s (ISI) sponsorship of Jabhat al-Nusra and then the Islamic State of Iraq and Syria (ISIS) and the Kurdistan Workers’ Party’s (PKK) sponsorship of the Democratic Union Party (PYD), have concluded that whereas state sponsors try to moderate their proxies, non-state sponsors do not have such concern. Reinoud Leenders and Antonio Giustozzi dwell on the external sponsorship provided by Hezbollah to pro-regime militias in Syria. Within this context, the authors have stated that Hezbollah “played a key role [in Syria] as it trained fighters, and embedded advisers and commanders within” pro-government militias such as the Abu Fadl al-Abbas Brigades, Imam Zain al Abidin Brigade, and al-Mahdi Brigade. In a similar vein, James Wither argues that Hezbollah has employed its own proxy fighters such as Quwat al-Ridha to support Assad Regime during the Syrian Civil War. Although non-state-led proxy warfare is not primarily the main focus of Wither’s intellectual attention, and he did not provide a comprehensive analysis of Hezbollah’s support for Quwat al-Ridha, he acknowledges that this is “an apparently novel situation where a non-state actor rather than a state has sponsored proxy forces.”
Arguably, the most comprehensive analysis regarding the non-state sponsorship has been provided by Assaf Moghadam and Michel Wyss. Their article entitled The Political Power of Proxies: Why Nonstate Actors Use Local Surrogates is the first work that systematically analyses the main characteristics of non-state sponsorship and addresses how and in what ways non-state sponsorship differs from state sponsorship. In doing so, they make a significant contribution to the literature on proxy wars. In their article, the authors formulate a set of hypotheses regarding non-state sponsorship and then use three case studies to test them: Al-Qaeda in the Arabian Peninsula’s support of local Sunni tribes in Yemen, the YPG’s sponsorship of various groups affiliated with the Syrian Democratic Forces, and Hezbollah’s support of the Lebanese Resistance Brigades. Drawing on case studies, the authors argue that, unlike state sponsors, non-state sponsors essentially use proxies to enhance their political power and legitimacy rather than for achieving military victory. Namely, the authors conclude that non-state sponsorship is qualitatively different from state sponsorship.
Having examined newly emergent literature on non-state-led proxy warfare, we will concentrate on the key features of state-led proxy warfare in the next section. By doing so, we aim to provide a framework that may help us to compare state-led and non-state-led proxy warfare.
The Core Characteristics of State-led Proxy Warfare
To identify whether, and if so, how non-state-led proxy differs from state-led proxy warfare, first, we need to identify the key characteristics of state-led proxy warfare by addressing the following questions one by one:
- For what reason(s) and under what circumstances do states prefer to conduct proxy warfare?
States use proxy warriors for a wide range of different reasons. Nevertheless, for simplicity of comparison, based on the existing literature, we have identified four main reasons and conditions promoting the use of proxy actors. Accordingly, states use proxy combatants for some or all of the following four reasons:
- In cases where an opponent/adversary does not pose an existential threat, states prefer to use proxy combatants rather than waging conventional war.
- The use of proxy fighters in armed conflicts offers states an opportunity to enable plausible deniability.
- The use of proxy fighters in armed conflicts offers states an opportunity to avoid the political, material, financial, and human costs, and risks of direct military intervention.
- A notable power asymmetry between states may lead the relatively weaker party to employ proxy fighters. By doing so, the weaker side aims to compensate for its military, financial or other deficiencies.
- With whom do states conduct proxy warfare?
States can conduct proxy warfare by using other state actors and/or a diverse range of armed non-state actors such as guerillas, terrorists, volunteer battalions, and private military companies.
- In what ways do states conduct proxy warfare?
State-led proxy warfare may take many forms. Briefly speaking, state sponsorship, among other forms of support, may generally involve providing some or all of the following elements:
- Financial support,
- Weapons and materials,
- Logistical support,
- Strategic advice and guidance,
- Military training,
- Intelligence assistance,
- Non-kinetic support (i.e., political, diplomatic, and moral support)
Al-Qaeda’s sponsorship of Caucasus Emirate
Al-Qaeda is a Salafi militant organization founded by Osama bin Laden in the late 1980s. Although al-Qaeda’s core leadership resides in the Afghanistan and Pakistan region, its political objectives go far beyond their borders. The group declares that its ultimate objective is the establishment of a global Islamic Caliphate. As such, since its inception in the late 1980s, al-Qaeda has attempted to initiate a global jihadist insurgency.
In line with its globalist outlook, al-Qaeda has established a wide range of branches and front groups operating around the world. Also, several already existing terrorist/insurgent organizations such as al-Shabaab have pledged loyalty to al-Qaeda over time, and by extension, have become part of al-Qaeda’s global network. Besides, several violent extremist groups that have loosely allied with al-Qaeda. In this regard, al-Qaeda has given a diverse range of support to home-grown radical groups that have distinct origins, organizational structures, and political agendas, to undermine sovereignty, territorial integrity, or political stability of target states.
Until recently, in the North Caucasus region, which is located in the southwestern part of the Russian Federation, the primary ally of al-Qaeda was the Caucasus Emirate, which was established as the successor to the Chechen Republic of Ichkeria in 2007. The Caucasus Emirate aimed at forming an independent state based on Islamic law in North Caucasus, and thus, declared a jihad on Russia. Because it had maintained close ties with al-Qaeda in practice, the group has generally been labeled as an al-Qaeda affiliate. Without a doubt, the Caucasus Emirate had been deeply associated with al-Qaeda’s global network. However, unlike other extremist movements that have clearly and unambiguously sworn absolute fealty to al-Qaeda’s leadership, the Caucasus Emirate had never declared formal allegiance to al-Qaeda. For this reason, the group can be best understood as the al-Qaeda-backed independent insurgent/terrorist organization rather than its offshoot or formal affiliate.
Historically, the North Caucasus region is of crucial importance for al-Qaeda's global jihadist agenda. In the words of al-Qaeda leader Ayman al-Zawahiri “the North Caucasus represented one of three primary fronts in the war against the West.” Due to the fact that al-Qaeda lacks the sufficient capabilities to mount a direct military campaign inside the North Caucasus and does not have powerful local branches or direct affiliates in that region, it needs to employ indigenous militant groups to create social and political instability. As a matter of fact, al-Qaeda’s central leadership has provided a varying degree of support for North Caucasian insurgents to attain its political objectives for several decades. That is to say, al-Qaeda's support for the jihadi groups in the North Caucasus predates the formation of the Caucasus Emirate. During the two Chechen wars, al-Qaeda provided weapons, military training, material assistance, and financial aid to Chechen rebels; sent fighters to assist local combatants in their struggle against Russian forces and carried out propaganda on behalf of Chechen jihad. After 2007, al-Qaeda and its affiliates continued to provide financial, training, and moral support to North Caucasian militants organized under the umbrella of the Caucasus Emirate.
In the years between 2007 and 2014, with the contribution of al-Qaeda’s assistance, the Caucasus Emirate was the most active and dangerous terrorist/insurgent group in North Caucasus. During this period, the Caucasus Emirate conducted several guerilla-style and terrorist attacks against the Russian security forces and civilian targets. One of the most well-known of these is the 2010 Moscow metro bombings, which killed 40 people and gained the Caucasus Emirate a worldwide reputation.
However, in the years between 2013 and 2015, with the killing of the group's founder and senior leader Doka Umarov, and the growing influence of ISIS over the North Caucasus insurgency, the Caucasus Emirate faced an existential crisis. As such, since late 2014, several top leaders and commanders of the organization have begun transferring their allegiance to ISIS. Thereafter, in June 2015, Abu Mohammad al-Adnani, who was the official spokesperson of ISIS, announced the establishment of a new governorate, dubbed Islamic State Caucasus Province. Currently, even the actual existence of the Caucasus Emirate is quite dubious. Analysts disagree on the current status of the Caucasus Emirate; some argue that small groups operating under the banner of the Caucasus Emirate are still exist, while others maintain that it was effectively replaced by Islamic State Caucasus Province.
Hezbollah’s support of Yemeni Houthis
Hezbollah is a Shia Muslim military, political, and social movement that emerged in Lebanon in 1982 in response to the Israeli occupation of Southern Lebanon that same year. Today, Hezbollah wields significant political power in Shia-majority areas of Lebanon, it fully participates in Lebanon’s democratic institutions; it employs and deploys sophisticated military capabilities as witnessed during the 2006 Israel-Hezbollah War; it has a welfare system that functions better than the state’s welfare system; and it has relied on its TV, satellite, radio, and digital media to conduct propaganda operations. So, it would not be wrong to say that Hezbollah is not only a violent non-state actor but also a state within a state.
Although Hezbollah is primarily based in Lebanon, it currently operates across many parts of the Middle East. This is because Hezbollah’s objectives are not limited to maintaining its domestic political power over Lebanon. In the name of anti-imperialism and/or anti-Zionism, the group also pursues a self-styled ‘resistance’ strategy against Israel and the USA. Besides, Hezbollah pursues sectarian geopolitical projects in parallel with the regional strategies of Iran which has long been the primary sponsor of its activities. In that sense, Hezbollah has staunchly opposed the subversive activities allegedly supported by Sunni-Arab states within the areas that Iran and its allies have traditionally viewed as belonging in an Iranian/Shia sphere of influence; and directly engaged in armed conflicts with anti-Shia/takfiri jihadists such as al-Qaeda (and by extensions al-Qaeda affiliates), and ISIS.
In the existing literature, Hezbollah has mainly been considered an Iranian proxy force. Indeed, since its formation, Hezbollah has always been armed and financed by Iran. Nevertheless, as several analysts have observed, Hezbollah also employs its own proxies. Apparently, among these groups is the Houthi movement who is a Shia-oriented insurgent group in Yemen.
The Houthi fighters seized Yemen’s largest and capital city, Sana’a, in 2014, and subsequently have been engaged in a fierce civil war against Yemen's Saudi Arabia-backed government. Many security analysts believe that, during this period, Houthis have largely been supported by Iran, which is Saudi Arabia’s main antagonist, and thus, in the existing literature, the Houthi movement has generally been considered as one of the Iranian proxies in the Middle East. Arguably, Iran has been and still is the foremost sponsor of Houthis, but that does not necessarily mean that Iran is the sole actor aiding the Houthi insurgents.
The Saudi-led coalition and Yemen's government have long accused Hezbollah of providing weapons, military advice, and training to the Houthi rebels. Also, the US State Department’s Country Reports on Terrorism 2019 declares that Hezbollah provides weapons and training to Houthi rebels. In a similar vein, many security analysts have believed that Hezbollah backs the Houthi movement. Yet, Hezbollah leader Hasan Nasrallah has consistently denied any involvement in Yemeni Civil War. However, Hezbollah's denial of its role in Yemen smacks of Russia's policy of plausible deniability employed during the armed conflicts in Ukraine in 2014.
This is, first, because Yemen’s government and the Saudi-led coalition fighting in Yemen have presented some evidence indicating that Hezbollah commanders provide military training to Houthi fighters. Second, in the past, some Hezbollah and Houthi members have admitted that Hezbollah experts help to train Houthis. Third, Houthi rebels have employed a wide range of advanced conventional weapons similar to those possessed by Hezbollah. Finally, Nasrallah’s statements strengthens the claims that Hezbollah provides sponsorship to Houthis. For example, in a televised speech in 2018, addressing Houthi militants, Nasrallah said: “I am ashamed that I am not with you. I wish I could be one of your fighters and fight under the guidance of your brave and dear leaders.” Following year, in another speech, Nasrallah declared that “[w]e are not ashamed that we have martyrs from Hezbollah in Yemen.”
As a consequence, in the current situation, it is really difficult to quantify the extent to which Hezbollah has assisted to the Houthis. Also, it is possible to think that the Yemeni government and Saudi-led coalition have been exaggerating Hezbollah’s role in Yemen to justify their aggression. Besides, it is very likely that, compared to Iran, Hezbollah offered relatively limited support to the Houthi rebels. However, there is sufficient evidence to reckon that Hezbollah has provided a range of assistance to Yemeni Houthis, and this has affected, more or less, the course of the civil war in Yemen.
The case studies reveal that in today’s world, politically motivated non-state armed actors exercising either state-like functions or having significant transnational military and financial assets provide external support to rebel groups to achieve political objectives. Succinctly speaking, key points of similarity and differences between state-led proxy warfare and non-state-led proxy warfare include the following points:
- The primary reason why states and non-state actors adopt the proxy warfare approach is always context-dependent. Like states, non-state armed groups may conduct proxy warfare due to a diverse range of different reasons including avoiding costs of direct attacks, maintaining plausible deniability, taking advantage of proxy fighters' local knowledge, and compensating for their military and financial deficiencies.
- Whereas state sponsors can conduct proxy warfare by employing armed non-state groups and/or other state actors, non-state sponsors substantially rely on other violent non-state actors whose political ideologies and identities are quite similar to theirs. Hence, while state-led proxy warfare can take the form of both conventional and irregular warfare, non-state-led proxy warfare generally takes the form of irregular warfare. However, this does not necessarily mean that non-state armed groups never employ a state actor as a proxy force. Given that we are living in an era in which non-state actors are playing an increasingly prominent role in world politics, this type of proxy-sponsor relationship may be the case in the future.
- The case studies show that like state sponsors, non-state sponsors provide financial assistance, weapons, equipment, military training, and some forms of non-military support such as propaganda to their proxies. The only difference is that because compared to most states, violent non-state groups have limited sources and capabilities, they offer relatively less support to their proxies.
Consequently, it would be correct to say that there are significant differences between the capabilities, organizational structures, and organizational cultures of state and non-state actors, and thus, how they use these to carry out proxy warfare. However, in the final analysis, non-state-led proxy warfare is, in substance, not that different from state-led proxy warfare.
Non-state-led proxy warfare may not be a brand-new phenomenon, but today it has become more widespread and important owing to the fact that non-state actors have increasingly been able to access greater economic and military sources. As emphasized earlier, this may have implications for the global security environment. Traditionally, armed non-state actors have been mainly associated with terrorism and insurgency warfare. Hence, states have primarily aimed at eliminating non-state threats through counterterrorism and/or counter-insurgency conceptual lenses. However, non-state-led proxy warfare demonstrates that non-state-armed groups are not limited to these modes of warfare, and they are also able to employ alternative methods. Hence, state actors may need to review their existing strategies used to counter non-state challenges.
 For example, see Karl W. Deutsch, “External Involvement in Internal Wars,” in Internal War: Problems and Approaches, ed. Harry Eckstein (New York: Free Press of Glencoe, 1964), 102; Bertil Duner, “Proxy Intervention in Civil Wars,” Journal of Peace Research 18, no.4 (December 1981): 353-354; Yaacov Bar-Siman-Tov, “The Strategy of War by Proxy,” Cooperation and Conflict 19, no.4 (November 1984): 263; Ideal Salehyan, Rebels Without Borders: Transnational Insurgencies in World Politics (Ithaca, New York: Cornell University Press, 2009), 44; Tyrone L. Groh, Proxy War: The Least Bad Option (Stanford, California: Stanford University Press, 2019). 27-32; Frank Hoffman and Andrew Orner, “The Return of Great-Power Proxy Wars,” War on the Rocks, September 2, 2021, https://warontherocks.com/2021/09/the-return-of-great-power-proxy-wars/; Dominic Tierney, “The Future of Sino-U.S. Proxy War,” Texas National Security Review 4, no. 2 (Spring 2021): 52.
 The term ‘political warfare’ seems tautological to some extent. War itself is fundamentally a political act. In other words, political entities wage a war to achieve their political objectives. So, using the adjective ‘political’ to describe a mode of warfare is somewhat superfluous.
 Linda Robinson et al., Modern Political Warfare: Current Practices and Possible Responses, (Santa Monica, CA: RAND Corporation, 2018), 219.
 Brendan Sozer, “Development of proxy relationships: a case study of the Lebanese Civil War,” Small Wars & Insurgencies 27, no.4 (2016): 639; Reinoud Leenders and Antonio Giustozzi, “Foreign sponsorship of pro-government militias fighting Syria’s insurgency: Whither proxy wars?” Mediterranean Politics (2020): 22.
 Candace Rondeaux and David Sterman, Twenty-First Century Proxy Warfare: Confronting Strategic Innovation in a Multipolar World Since the 2011 NATO Intervention (Washington D.C, New America: February 2019), 50-52.
 Christopher Phillips and Morten Valbjørn, “‘What is in a Name?’: The Role of (Different) Identities in the Multiple Proxy Wars in Syria,” Small Wars & Insurgencies 29, no. 3 (2018): 428.
 Leenders and Giustozzi, “Whither proxy wars?” 1-30.
 James K. Wither, “Outsourcing warfare: Proxy forces in contemporary armed conflicts,” Security and Defence Quarterly 31, no.4 (2020): 21.
 Assaf Moghadam and Michel Wyss, “The Political Power of Proxies: Why Nonstate Actors Use Local Surrogates,” International Security 44, no.4 (Spring 2020): 128-154.
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 Ariel Cohen, Russia’s Counterinsurgency in North Caucasus: Performance and Consequences (Carlisle Barracks, PA: United States Army War College, 2014), 49.
 Sergey Markedonov, “Radical Islam in the North Caucasus Evolving Threats, Challenges, and Prospects,” Center For Strategic & International Studies, November 2010, 10; Gordon M. Hahn, “Getting the Caucasus Emirate Right,” Center For Strategic & International Studies, August 2011, 5; Cohen, Russia’s Counterinsurgency, 27; Thomas Visel, Nationalist to Transnational Insurgency: State Repression and Violent Extremist Scale Shift (Fort Leavenworth, Kansas: School of Advanced Military Studies United States Army Command and General Staff College, 2016, 21-22); Grazvydas Jasutis, “The Rise and Decline of the Caucasus Emirate,” Geneva Centre for Security Policy, no.9, July 2016, 4.
 Hahn, “Getting,” 2; 21; Cohen, Russia’s Counterinsurgency, 48-49; “Caucasus Emirate,” National Consortium for the Study of Terrorism and Response to Terrorism (START), University of Maryland, last modified January 2015, https://www.start.umd.edu/baad/narratives/caucasus-emirate; Jasutis, “Caucasus Emirate,” 4.
 Marta Ter, “The Caucasus Emirate, the Other Russian Front,” Notes Internacionals, No. 129, November 2015, 3.
 Anna Borshchevskaya, “The Islamic State Comes to Russia,” The Washington Institute for Near East Policy, January 26, 2016, https://www.washingtoninstitute.org/policy-analysis/islamic-state-comes-russia.
 On Caucasus Emirate’s current status, see Regis Gente, “Is this the end of the Caucasus Emirate?” Open Democracy, June 29, 2015, https://www.opendemocracy.net/en/odr/is-this-end-of-caucasus-emirate/; “The North Caucasus Insurgency and Syria: An Exported Jihad?,” International Crises Group, March 16, 2016, 2, https://www.crisisgroup.org/europe-central-asia/caucasus/north-caucasus/north-caucasus-insurgency-and-syria-exported-jihad; Nick Sturdee and Mairbek Vatchagaev, “ISIS in the North Caucasus,” Newlines Institute for Strategy and Policy, October 26, 2020, https://newlinesinstitute.org/isis/isis-in-the-north-caucasus/.
 Lina Khatib, “How Hezbollah holds sway over the Lebanese state,” Chatham House, June, 2021, 2-31, https://www.chathamhouse.org/sites/default/files/2021-06/2021-06-30-how-hezbollah-holds-sway-over-the-lebanese-state-khatib.pdf; Frank Hoffman, Conflict in the 21st Century: The Rise of Hybrid Wars (Arlington, Virginia: Potomac Institute for Political Studies, 2007), 35-42; Colin P. Clarke, “How Hezbollah came to dominate information warfare,” The Jerusalem Post, September 17, 2017, https://www.jpost.com/Opinion/How-Hezbollah-came-to-dominate-information-warfare-505354.
 “Saudi Arabia accuses Iran, Hezbollah of aiding Houthis after deadly missile attack,” The Times of Israel, December 26, 2021, https://www.timesofisrael.com/saudi-arabia-accuses-iran-hezbollah-of-aiding-houthis-after-deadly-missile-attack/; “ Yemen government says Hezbollah fighting alongside Houthis,” Reuters, February 24, 2016, https://www.reuters.com/article/us-yemen-security-idUSKCN0VX21N;
 “Country Reports on Terrorism 2019,” Washington, DC: U.S. Department of State, June 2020, https://www.state.gov/reports/country-reports-on-terrorism-2019/.
 Cameron Glenn, “Who are Yemen's Houthis?” Wilson Center, April 29, 2015, https://www.wilsoncenter.org/article/who-are-yemens-houthis;
Seth G. Jones, “The Iranian and Houthi War against Saudi Arabia,” Center for International and Strategic Studies, December, 2021, 5-13, https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/211221_Jones_IranianHouthi_SaudiArabia.pdf?fn1d98tAhj7yOUr.IncppMueLOC4kv83; Matthew Levitt, “Hezbollah’s Regional Activities in Support of Iran’s Proxy Networks,” Middle East Institute, July 26, 2021, https://www.mei.edu/publications/hezbollahs-regional-activities-support-irans-proxy-networks.
“Lebanon's Hezbollah denies sending weapons to Yemen,” Reuters, November 20, 2017, https://www.reuters.com/article/us-mideast-crisis-syria-nasrallah-idUSKBN1DK22D; “Hezbollah rejects calls for minister to quit over Yemen comments,” Reuters, November 11, 2021, https://www.reuters.com/world/middle-east/hezbollah-chief-rejects-calls-resignation-minister-who-sparked-gulf-row-2021-11-11/.
“Saudi coalition shows footage of alleged Hezbollah involvement in Yemen war,” The Jerusalem Post, December 26, 2021, https://www.jpost.com/middle-east/article-689814. “Yemen army kills Hezbollah military expert in Marib,” Arab News, December 9, 2021, https://www.arabnews.com/node/1984261/middle-east.
 Alexander Corbeil and Amarnath Amarasingam, “The Houthi Hezbollah
Iran's Train-and-Equip Program in Sanaa,” Foreign Affairs, March 31, 2016, https://www.foreignaffairs.com/articles/2016-03-31/houthi-hezbollah; “Lebanon’s Hizbollah and Yemen’s Houthis open up on links,” Financial Times, May 8, 2015, https://www.ft.com/content/e1e6f750-f49b-11e4-9a58-00144feab7de; “Houthi prisoner admits: ‘Hezbollah expert came to train us’,” Arab News, January 11, 2018, https://www.arabnews.com/node/1223831/middle-east.
 Yaakov Lappin, “Iran views Houthi attacks as 'experiment lab' for its weapons, doctrines,” Israel Hayom, July 11, 2021, https://www.israelhayom.com/2021/07/11/iran-views-houthi-attacks-as-experiment-lab-for-its-weapons-doctrines/; “The terror of Iranian weapons.. Houthi Forces Threaten Gulf Security,” Abaad Studies and & Research Center, February 13, 2018, https://abaadstudies.org/news.php?id=59756.
 “Nasrallah’s message to Yemen’s Houthi leaders: ‘I wish I could fight with you,” Al Arabiya News, last modified May 20, 2020, https://english.alarabiya.net/features/2018/06/30/Nasrallah-s-message-to-Yemen-s-Houthi-leaders-I-wish-I-could-fight-with-you-.
 Levitt, “Proxy Networks.”