Rethinking GCC Security: Lessons From the Saudi-Led Coalition’s Intervention in Yemen

Abstract

This article examines the security implications of the Saudi-led Arab Coalition’s military intervention in Yemen (2015–2022), launched to restore the legitimate authority seized by the Houthis, officially known as Ansar Allah (Partisans of God)—an Iran-aligned Zaydi Shia group. It addresses two core questions: why did the coalition fail to achieve its stated objectives, and what lessons can be drawn for the Gulf Cooperation Council’s (GCC) future security frameworks? In doing so, the article explores three interrelated dimensions of the coalition’s intervention and the strategic lessons derived from them. First, the motives behind and consequences of Saudi Arabia’s militarised approach. Second, the strategic, institutional and operational shortcomings of the ad hoc coalition, and the resulting need for a more strategic security alliance in the future. Third, the limitations in the reliability of GCC’s extra-regional security partnerships, particularly with the United States, and the need to rethink future alignments.

Introduction

On 25 March 2015, Saudi Arabia launched a military intervention in Yemen, leading a coalition—commonly referred to as the Arab Coalition—that included all GCC states except Oman, as well as several non-GCC allies. This coalition initiated Operation Decisive Storm, later renamed Operation Restoring Hope. Its primary objective was to restore the Internationally Recognised Government of Yemen (IRGY) by expelling the Iran-backed Houthi rebels—Ansar Allah—from Ṣana’a and other key territories seized in late 2014. King Salman justified the intervention at the 26th Arab League Summit in Sharm el-Sheikh (28–29 March 2015) citing the Yemeni President’s appeal, the Arab Treaty of Joint Defense, Article 51 of the United Nations Charter, and UN Security Council Resolution 2216, a legal support until Yemen was “stable and safe” (Al Arabiya, 2015). From Riyadh’s perspective, therefore, the campaign served a dual purpose: re-establishing Yemeni state authority and curtailing Iran’s regional influence, a linkage underscored by former Saudi Foreign Minister Adel al-Jubeir, who framed the operation as “not a war of choice; this was a war of necessity” (CNN, 2016).

The Saudi-led Arab Coalition’s intervention marked a critical juncture in Gulf security politics and, more specifically, in Saudi Arabia’s Yemen policy. It demonstrated shortcomings in Saudi Arabia’s militarised approach, the ad hoc coalition, and the reliability of the GCC extra-regional security partners. First, the decision to intervene militarily reflected Riyadh’s shift from its historically non-direct interventionist posture in Yemen, a transition towards a more assertive interventionist posture in the region, seeking enhanced strategic autonomy and diversified security partnerships. This shift was driven primarily by concerns over Iran’s expanding influence, perceptions of diminishing U.S. engagement in the region, post-Arab Spring instability, and recent changes in Saudi leadership. However, the military intervention yielded unintended repercussions, including the exacerbation of the humanitarian crisis, heightened vulnerability of Saudi Arabia and the UAE to Houthi attacks, and emboldenment of the Houthis. Second, the military campaign secured initial battlefield gains, chiefly by ousting the Houthi forces from significant territories, particularly in southern Yemen, and symbolically signified a gesture of solidarity with Yemen and a nascent move towards collective defence initiatives within the Arab world. As Anwar Gargash, the former UAE Minister of State for Foreign Affairs, remarked, it represented “a new page of Arab cooperation to keep the region secure” (Roberts & Shaheen, 2015). Nevertheless, the coalition internationalised the conflict, affected the growing intra-GCC tension, and revealed profound shortcomings in the coalition’s strategic coherence—divergent political objectives between Riyadh and Abu Dhabi—its institutional robustness, as evidenced by partner defections and inadequate coordination with local forces, and its operational effectiveness in confronting the Houthis’ hybrid guerrilla tactics. Ultimately, while the United States, the United Kingdom, and France extended logistical and operational support to the coalition, Washington, in particular, fell short of meeting the expectations of Riyadh and Abu Dhabi. The trajectory of U.S. policy towards the Yemeni conflict—during and after the coalition’s campaign, from the Obama administration through Trump’s second term—has fostered perceptions of inconsistency, insufficiency, and strategic unpredictability. From earlier strained U.S.–Saudi relations and constraints on arms transfers, to the partial withdrawal of military assets and recent ambiguity surrounding President Trump’s second-term stance, these developments have prompted GCC states to question the reliability of their traditional Western partnerships and to pursue more diversified strategic alignments.

These dynamics raise the core puzzle that motivates this study: Why did an intervention launched to restore Yemeni legitimacy and hope fail to achieve its stated objectives? And what lessons can be drawn for the GCC’s future security frameworks? To address these questions, the article explores three more sectional questions: What motivated Saudi Arabia to intervene militarily in Yemen? How was the coalition built, managed, and conducted to weaken its effectiveness? How did extra-regional security partner commitments, particularly the U.S., and expectations about them, undermine the military campaign and shape Saudi Arabia’s doubts about the reliability of Washington and future alignment diversification?

While existing literature has extensively focused on the GCC’s defence spending, professionalisation, and diversification of external partnerships, far less attention has been paid to its capacity for collective military action during high-intensity contingencies—most notably the Saudi-led Arab Coalition’s intervention in Yemen. This article, therefore, pursues two objectives. First, it advances debates on GCC security politics. Second, it addresses the empirical gap identified above by analysing the motives and consequences of the coercive interventionism and by assessing the coalition’s institutional structure and quality alongside the credibility and commitment of key security partners, particularly the United States. In doing so, the study’s findings also derive lessons for future GCC security architectures.

Methodologically, this study employs a mixed-methods design that combines elite interviews, content analysis of official communiqués, data from the Yemen Data Project, specialist reports, press coverage, and relevant academic literature. It is further informed by the author’s long-term experience with Yemen’s conflict dynamics and the agendas of both local and external actors. The rest of the article proceeds in three sections. The first section analyses Saudi Arabia’s motives and implications of its militarised intervention in Yemen. The second section assesses the shortcomings of the coalition’s structure, agenda, and battlefield conduct. The third section evaluates the extent of credibility and commitment shown by the GCC’s long-standing Western partners, particularly the U.S., during the coalition campaign in Yemen.

Military Interventionism

Saudi Arabia’s engagement in Yemen has historically fluctuated between military and non-military interventions, shaped by the dynamics of Saudi-Yemeni relations and broader regional political considerations (Tynan, 2020). Saudi military involvement has encompassed both direct and indirect interventions aimed at addressing territorial, security, and ideological concerns. Notably, direct military interventions took place in the 1920s and 1930s against the Yemeni Imams, and in 1969 against South Yemen over territorial disputes, while indirect interventions were undertaken during the Egypt-backed Yemeni Revolution (1962–1970). More recently, direct military campaigns have targeted the Houthis, initially from 2009 to 2010, and again from 2015 to 2022.

Although largely motivated by security and ideological concerns, the Saudi-led military intervention in Yemen was framed as a measure of last resort, supported by legal and political justifications. Within this framework, Saudi Arabia articulated its actions through three primary narratives. First, it claimed that the intervention responded to former Yemeni President Abd Rabbuh Mansur Hadi’s appeal under Article 51 of the UN Charter (collective self-defence), endorsed by UN Security Council Resolution 2216. Second, it framed the intervention as an act of self-defence against a broader regional threat posed by the collapse of Yemen and Iranian backing for the Houthis. Former Saudi Foreign Minister Adel al-Jubair emphasised the defensive nature of the campaign, characterising it as a ‘war of necessity’ to defend both Saudi Arabia and the legitimate government of Yemen (CNN, 2016). Third, the justification also drew upon the Houthis’ history of failed negotiations and violations of previous peace agreements, ranging from the Sa’ada wars (2004–2010) to the 2014 Peace and Partnership Agreement.

The military intervention in Yemen, while framed as a response to the immediate threat posed by the Iran-backed Houthis, must also be situated within a broader set of external conditions. These include the upheavals of the Arab Spring, shifts in U.S. regional primacy and strategy, and the transformation of Saudi Arabia’s foreign policy decision-making. Collectively, these dynamics compelled Riyadh to act more proactively and independently in pursuit of its security imperatives and regional leadership status (Darwich, 2018). First, the Arab Spring revolutions—initially driven by popular movements and later enabling Islamist groups, including the Muslim Brotherhood (MB), to gain significant influence—were perceived by Saudi Arabia as a serious challenge to its regional position, echoing the ideological contestations of the pan-Arab nationalist movements of the 1960s. To contain these perceived threats, Riyadh adopted a double security approach against both the Iranian influence and the MB-associated revolutionary actors, through military interventions in Bahrain (2011) and Yemen (2015), political support for counter-revolutionary forces in Egypt and Libya, and a political and diplomatic blockade against Qatar during the 2017 Gulf crisis. Strategically, Saudi Arabia also engaged in international coalitions and significantly increased its arms expenditure (Cordesman, 2018). Collectively, these measures marked Riyadh as a post-Arab Spring ‘desert warrior’(Al-Rasheed, 2010).

Second, regional anxieties over the perceived decline of U.S. unilateral dominance—evident in Washington’s gradual strategic disengagement from the Middle East, from the Obama administration’s softening with Iran and concurrent ‘Pivot to Asia’ strategy to the Biden administration’s strained relations with Saudi Arabia—have driven Gulf Arab monarchies, particularly Saudi Arabia, to reassess their security frameworks by acting more independently in security matters and proactively pursuing greater autonomy in foreign decision-making.

Third, the transformation of Saudi leadership since King Salman’s ascension to power in 2015 marked a significant shift towards foreign policy assertiveness, moving away from the kingdom’s traditionally cautious approach to a more proactive foreign posture and increased centralisation of authority. King Salman, a member of the powerful Sudairi Seven alliance, departed from King Abdullah’s more consensual approach. He appointed his immediate family, most notably his son Mohammed bin Salman (MbS), as Deputy Crown Prince, Minister of Defence, and eventually Crown Prince (Karim, 2017).

Despite these mounting security concerns and evolving shifts in Saudi foreign policy, a critical question remains: Why did Saudi Arabia wait six months after the Houthis’ capture of Sana’a before intervening? Three possible explanations can be identified. First, the royal transition following King Abdullah’s death preoccupied the Saudi leadership. Second, the earlier death of Crown Prince Sultan in 2011, who had overseen Yemen affairs through the Special Committee for Yemen Affairs, resulted in policy discontinuity and disrupted coordination in Saudi Yemen policy (Al-Iryani, 2022). Third, there were misperceptions and underestimations of the Houthis’ objectives and capabilities. Regionally, Saudi Arabia, along with other states, misjudged the Houthi threat and instead prioritised containing the MB in the aftermath of the Arab Spring. These misjudgements were further reinforced by anti-Islah party (a Yemeni Muslim Brotherhood-affiliated party) actors within Yemen, particularly members of former President Saleh’s General People’s Congress (GPC), who perceived the Houthis’ advance as a means to counterbalance the influence of the Islah party (Shuja Al-Deen, 2020). This mischaracterisation of the threat emboldened the Houthis to fight Saudi-aligned Salafist groups in Dammaj, Sa’ada province, in both 2011 and 2013 as part of their broader strategy to advance towards Sana’a.

The Consequences of Military Intervention

The Saudi-led military intervention in Yemen had far-reaching consequences for both the country and the wider region. First, it heightened vulnerabilities for the GCC states, particularly Saudi Arabia and the UAE. Until December 2021, Saudi Arabia alone endured approximately 430 missile and 851 drone attacks by the Houthis (Reuters, 2021). Second, the intervention caused a massive humanitarian crisis. According to the Yemen Data Project, the coalition waged around 24,800 air raids during the coalition operations, which resulted in significant collateral damage to civilians and infrastructure, including the deaths of over 9,200 civilians (Yemen Data Project, n.d). Third, the intervention paradoxically strengthened the Houthis’ position. By framing themselves as defenders against foreign aggression, the Houthis consolidated domestic alliances—such as their temporary alignment with former President Saleh—and deepened their ties with Iran, which viewed the war as a means of countering Saudi regional influence (Juneau, 2021). Fourth, the intervention, coupled with the Qatar blockade by the Arab Quartet (Saudi Arabia, the UAE, Bahrain, and Egypt)—which followed the 2017 GCC crisis, during which these fellow states severed diplomatic and economic ties with Qatar over allegations of support for terrorism and rapprochement with Iran—has pushed other GCC states to seek alternative security arrangements. Qatar, for example, turned to Turkey (Bakir, 2023). Oman also viewed the Saudi and Emirati military presence in Yemen’s al-Mahra province with suspicion and apprehension, considering it part of its traditional sphere of influence. Fifth, by falling short of its initial objectives, the intervention has contributed to the emergence of de facto statehood in Yemen. Semi-autonomous regions emerged along conflict lines, with the Houthis controlling significant parts of the north, the Southern Transitional Council (STC), backed by the UAE, controlling much of the south, and Saudi Arabia maintaining influence in Hadramout (Al-Dahab, personal communication, February 15, 2024). This fragmented post-intervention situation resembles the earlier failed initiatives, such as the 2011 Gulf Initiative and subsequent National Dialogue Conference, which proposed a federal constitution and governing system.

A Fragile Military Coalition

Similar to the broader dilemma of shifting alliances in the Middle East (Darwich, 2019; Walt, 1990), the GCC has historically struggled to establish a robust and unified security alliance, despite multiple initiatives. Efforts like the Peninsula Shield Forces (1985), the Cooperation Belt (1997), the GCC Joint Defence Agreement (2000), and the GCC Unified Military Command (2013) all fell short of this objective (Farouk, 2019). This persistent failure can be attributed to both internal and external factors. Internally, despite facing common threats, particularly from Iran, GCC states possess heterogeneous military capabilities and divergent threat perceptions. Externally, their continued reliance on Western security providers, particularly the UK and the U.S., has inhibited the development of an independent and cohesive regional security alliance.

In contrast to formal alliances, Saudi Arabia favours ad hoc coalitions to address security concerns, as in Yemen. The formation of such coalitions aligns with the deeply embedded Bedouin concept of ‘faz’ah’, the provision of immediate support and solidarity within a community during times of crisis. Such coalitions serve a range of strategic advantages for Saudi Arabia, the GCC, and participating states. They offer mission-specific flexibility compared to formal treaties (Morey, 2016); demonstrate solidarity with vulnerable nations; advance the political or economic agendas of certain participating states (e.g., the UAE and Egypt) (Dogan-Akkas, 2021; Mason, 2018); facilitate burden-sharing in security provision; and enhance Saudi Arabia’s symbolic reputation as convener and leader of regional coalitions. Indeed, this preference and norm proved limited in the case of the coalition in Yemen, as shifting political realities within GCC states produced divergent responses—ranging from bandwagoning, whereby weaker states align with a stronger power to share in the benefits of its dominance (Walt, 1985), to hedging, a strategy involving cautious engagement and balancing amid uncertainty to avoid the risks of over-commitment to any single power (Kuik, 2021)—as well as efforts by some states to maintain strategic autonomy.

In the aftermath of the Arab Spring and the subsequent assertive foreign policy of King Salman, coalition-building became a defining feature of Saudi Arabia’s evolving security policy. Riyadh proactively led or joined several regional and international coalitions: the Arab Coalition in Yemen (March 2015), the Islamic Military Alliance to Fight Terrorism (IMAFT) (December 2015), the Global Coalition against Islamic State in Iraq and Syria (ISIS) (February 2016), and the anti-Qatar Arab Quartet (June 2017) (Miller & Cardaun, 2020, pp.7-8). This strategic shift can be partly attributed to a perceived decline in the reliability of Western security partners, particularly the U.S., for its ‘Asia Pivot’ strategy, support of the Arab Spring uprisings, and engagement with Iran through the Joint Comprehensive Plan of Action (JCPOA) in 2015 (Miller & Cardaun, 2020, pp.5-6).

Saudi Arabia tirelessly attempted to enlist states to deploy to Yemen. It employed various strategies such as flattery, bargaining, and incentives. However, several countries responded and participated diversely over the course of the war: rejections, bandwagoning, hedging, withdrawals, and even shifting courses of participation. These responses and patterns of participation arose from concerns about the intervention’s legal legitimacy, political objectives, and operational difficulties.

GCC, Arab, and a number of Islamic and Western states were invited to join the coalition. Three states rejected and maintained neutrality: Pakistan, a traditionally close ally (Ali & Ahmad, 2021); Malaysia (Miller & Cardaun, 2020, p.15); and Algeria (Cafiero, 2016). However, other members of the GCC and the broader Arab world ultimately joined the coalition: Egypt, Morocco, Jordan, Kuwait, Sudan, the UAE, Bahrain, and Qatar. Meanwhile, Turkey, the U.S., the UK, and France provided logistical support.

President al-Sisi of Egypt, a member of the Arab Quartet, joined the coalition to signal Arab solidarity and to gain economic rewards from the Saudis and the Emiratis. Egypt’s role, however, was largely symbolic, shaped by a cautious approach to avoid repeating the military quagmire of the 1960s. Sudan contributed to the coalition by deploying thousands of troops from the Rapid Support Forces to support military operations along the southern borders of Saudi Arabia, as well as in northwestern provinces and the western coastal plains of Yemen. Former President Omar al-Bashir’s decision to join the coalition was driven by financial incentives and a desire to appease the Gulf leaders concerned about his relations with Iran and the MB (Heras, 2017). Morocco initially deployed six F-16 fighter jets in the first year, one of which was lost over Yemen. Its role gradually declined due to the mounting setbacks of the operation, the Qatar crisis, and tensions with Saudi Arabia over its 2018 stance on the 2026 World Cup bid (Young, 2019). Similarly, Jordan initially deployed a limited number of fighter jets but later withdrew due to the regional developments and a growing recognition of the limitations of a purely military approach (Kilani, 2019).

Turkey’s position on the Yemen conflict and coalition, according to Munassar (2021), “shifted mainly from bandwagoning to hedging. In contrast to its proactive regional policy, Turkey seems passive in its approach to the Yemen conflict’’ (p. 4). Initially, Turkey expressed support for the coalition by providing logistics, humanitarian aid, and diplomatic engagement through backchannel efforts. The support was partly motivated by Ankara’s interest in securing support from Saudi Arabia in Syria and enticing a favourable Saudi stance towards the Islah party, a Yemeni MB-affiliated political party closely aligned with Turkey’s ruling party. However, Turkey later withdrew its support in the context of growing domestic difficulties and the diplomatic dispute with the Arab Quartet over the Qatar blockade. This shift marked a recalibration of Turkey’s relations with Saudi Arabia, the UAE, and Iran.

The level of participation by GCC countries was significantly shaped by internal and regional dynamics, including power asymmetries, divergent threat perceptions, and the intra-GCC divide (Bianco, 2020). Oman, for example, known for its quiet diplomacy and hedging strategy, maintained a neutral stance to preserve its historical relationship with Iran and to sustain a delicate balance between Tehran and Riyadh (Binhuwaidin, 2019; Hamdi & Salman, 2020). Throughout the war, Oman has actively engaged in mediation efforts between the conflicting parties in Yemen, with an allegedly relative inclination towards the Houthis. Kuwait, in addition to its initial military support, hosted the Yemen peace talks in 2016.

The UAE and Bahrain, sharing similar political and ideological views, readily joined the coalition as staunch allies of Saudi Arabia, acting as ‘bandwagoneers’. All three were bound by a shared threat perception of political Islam (Mason, 2018, 2023; Miller & Verhoeven, 2020). Qatar, despite its initial alignment, adopted a more independent and at times oscillating foreign policy posture. This included support for the Yemeni uprisings during the Arab Spring, joining and later withdrawing from the coalition, and even launching media campaigns against the coalition. This volatile behaviour confused and undermined Saudi Arabia’s regional plans (Yom, 2018). Moreover, the UAE and Qatar, as both GCC second-tier powers situated within two opposing regional blocs (the Arab Quartet versus Turkey-Qatar-MB alliance), played competing roles in the Yemeni conflict, shaped by divergent geopolitical ambitions and ideological cleavages (Quilliam, 2020). Ultimately, the Yemen intervention and Qatar blockade widened GCC fissures, fuelled trends of foreign policy autonomy, mutual mistrust, and the erosion of cohesion norms within the bloc (Bianco & Stansfield, 2018; Keating & Abbott, 2021; Sadiki & Saleh, 2020; Ulrichsen, 2020). As Hoetjes (2021) argues, “disagreements between the Gulf monarchies heightened by hyper-nationalist tendencies inhibit the ability of this sub-regional organisation to facilitate peacebuilding in Yemen” (p. 1).

Becoming a ‘Saudinised’ and ‘Emiratised’ Coalition

The term ‘Arab Coalition’ arguably became a misnomer, reflecting a primarily bilateral effort by Saudi Arabia and the UAE. Even these two remaining core members harboured divergent strategic visions for Yemen (Parker, 2021), making distinct ‘Saudinised’ and ‘Emiratised’ strands of the intervention. These clashing objectives of the two Gulf Arab states—along with their aligned Yemeni forces—directly impacted the combat operations, including the logistical distribution, the effectiveness of intelligence sharing, the degree of political polarisation, and overall operational performance. These dynamics are further discussed in the forthcoming section.

The coalition strategies of Saudi Arabia and the UAE in Yemen diverged, indicating that the latter adopted a more autonomous posture and pursued a distinct agenda, in contrast to its initial bandwagoning alignment with Saudi Arabia. In terms of security, Saudi Arabia adopted a northern Yemen-oriented approach aimed at restoring political legitimacy, deterring the Iran-backed Houthis, and securing its borders. For Saudi Arabia, Northern Yemen remains a strategic concern due to its geographical proximity, political weight, demographic intensity, and entrenched tribal networks. In contrast, the UAE adopted a southern Yemen-oriented approach, focused on countering the Houthis in the south, containing al-Qaeda in the Arabian Peninsula (AQAP), and securing vital maritime lines (Salisbury, 2020). Politically, Saudi Arabia primarily engaged with traditional northern actors, IRGY, and the Islah party to preserve the de jure Yemen authority and offset the Houthis. While the UAE navigated two main allies: STC with its Security Belt Forces, and exclusively the northern-based Saleh family network, particularly Brig-General Tareq Saleh—the nephew of former President Saleh—who leads UAE-backed forces in parts of the Red Sea coast.

The UAE’s southern Yemen policy stemmed from: (1) historical sympathy for southern grievances since the 1994 Secession War; (2) a strategic aspiration to project influence in vital maritime routes, including the Gulf of Aden, Socotra Island, and key seaports such as Aden; and (3) an ideological perception that an independent South would be free from the influence of northern actors, particularly the MB and Zaydi elites. Leveraging the political, ideological, and geographic cohesion among southern actors, the UAE helped consolidate a relatively unified southern entity capable of resisting the Houthis, containing the MB, and ultimately asserting a stronger position in the pursuit of secession.

Although southern Salafists, particularly the Giant Brigades, initially rejected the idea of southern secession, they increasingly came to view the South as an ideal space for advancing their ideological vision, free from the perceived dominance of Zaydism and the MB in the north (Juneau, 2020). Consequently, Yemen witnessed widespread debate over the shifting objectives of the intervention and the evolving trajectory of the coalition, with criticism of Saudi Arabia for appearing to overlook these developments.

By 2019, the UAE adjusted its Yemen policy by withdrawing its military forces from the country. Emirati scholar Al-Ketbi (2020) suggests that this decision was driven by a reevaluation of the UAE’s foreign policy direction (p.396), shaped by the growing complexities of Yemen’s internal conflict and mounting international pressure (Said & Kalin, 2023). Although the UAE achieved notable military success, particularly in southern Yemen, it ultimately recognised the stagnation of the broader conflict, with its influence sustained through local allies it had trained and armed, such as the STC-led militias and Tareq Saleh’s National Resistance Forces in the Red Sea region. Simultaneously, the UAE faced Houthi attacks, diverging priorities with Saudi Arabia, and increasing criticism from both the Yemeni public and government regarding its southern-oriented strategy. This shift marked a transition in Abu Dhabi’s role within the coalition—from initial bandwagoning with Riyadh, to a more autonomous policy, and ultimately to a pronounced buck-passing strategy (Dogan-Akkas, 2021): a posture whereby a state seeks to shift the burden of confronting a shared threat onto another actor (Mearsheimer, 2001).

Three Overlapping Phases of Operation

The coalition’s operation in Yemen unfolded across three overlapping phases: a decisive military advance (2015), a protracted civil-military campaign (2016-2022), and a gradual withdrawal (since 2017). Over this period, the operation produced mixed outcomes. While the initial year achieved significant territorial gains, these came at the cost of substantial civilian casualties.

The first phase, characterised by airstrikes, ground offensives, and a naval blockade, achieved notable successes in the south and east. In support of Yemeni government forces and local resistance groups, the coalition’s Operation Decisive Storm, launched on March 25, 2015, neutralised Houthi-Saleh missile capabilities. This was followed by Operation Restoring Hope (April 21, 2015), also known as the ‘Golden Arrow,’ a kinetic operation which successfully dislodged Houthi-Saleh forces from Aden by July 2015. By August, five southern provinces and the resource-rich Marib region were also retaken. However, extensive aerial bombardment resulted in infrastructure destruction and civilian casualties. Targeting the residences and bases of Houthi-Saleh leaders proved counterproductive as it failed to eliminate their leadership or alter their course towards a political resolution (Shield, 2018).

The second phase drew on a civil-military campaign outlined in the early Operation Restoring Hope in April 2015, combining military pressure with political negotiation and economic reconstruction. Yet, progress in non-Houthi-controlled areas was hindered by limited economic recovery, and the political track stalled. The coalition’s adherence to the ‘Three Terms of Reference’—the Gulf Initiative, the Outcomes of the National Dialogue Conference, and UNSC Resolution 2216—to resolve the conflict failed to adapt to evolving realities. This rigidity paralysed peace efforts from the 2016 Kuwait Talks to the 2019 Riyadh Agreement. Two factors, however, help explain the coalition’s initial territorial gains: first, the Houthis were at that time relatively disorganised and lacked a strong support base in the south; second, the flat, open terrain of the southern and eastern regions afforded strategic advantages to coalition forces, especially in terms of air and naval superiority.

The third phase, beginning around 2017, saw a gradual drawdown of coalition members, officially and operationally coinciding with the GCC crisis. This shift stemmed from the growing realisation that military victory was unlikely, mounting international scrutiny over the humanitarian crisis in the country, and the risk of escalation in the region. Coalition operations, particularly in the north, gradually became reactive and defensive in nature. A notable example was the failed attempt to save Nihm district, just 20 km from Sana’a, in February 2016. Meanwhile, Houthi tactics had evolved into a strategy of regaining lost territory through counteroffensives, coupled with missile and drone attacks on Saudi Arabia and the UAE (Williams & Shaan, 2020). This shift forced Saudi Arabia to prioritise border security and the defence of recently liberated areas. In Yemen, it prompted debate over the coalition’s failure to advance on all fronts—an approach that, if adopted, might have weakened or overwhelmed the Houthis.

However, the Houthi offensives gained momentum due to four key factors. First, they capitalised on political compromises such as the 2018 Stockholm Agreement, which established a ceasefire in Hodeidah. This enabled the Houthis to solidify control over the strategic Red Sea port and its extensive coastlines, preserving smuggling routes and posing threats to shipping lanes. Second, the reduction in coalition air defences—including the drawdown of joint terminal attack controllers (JTACs), the scaling back of Patriot and Pantsir systems, and subsequent U.S. withdrawal of Patriot batteries from Saudi Arabia in mid-2021—lessened pressure on Houthi positions, particularly following the withdrawal of key Emirati support. Third, intra-conflicts between the Yemeni government and the STC diverted resources and attention from critical fronts such as Marib (Almeida & Knights, 2020). The UAE’s airstrikes on the Yemeni government forces near Aden in August 2019 deepened tensions between the Yemeni government and the UAE. The Riyadh Agreement of November 2019 sought to address this through a power-sharing arrangement (Jalal, 2021). Fourth, the Houthis’ growing combat experience, improved weaponry, and entrenchment in mountainous terrain—where they enjoyed local support and logistical advantages—bolstered their resilience as the conflict moved northwards, approaching Sana’a and its surrounding governorates such as Marib, al-Jawf, and al-Bayda.

Fighting a Semi-State Houthis

The Yemen war exhibits characteristics of both asymmetric warfare and operational challenges faced by military operations in Afghanistan. Evidences suggest the coalition faced three major operational challenges in Yemen: limited experience in counterinsurgency warfare, deficiencies in intelligence and coordination, and structural organisational constraints.

First, the coalition lacked adequate experience and training in counterinsurgency warfare in a rugged and mountainous environment like Yemen. Indeed, the Saudi army had minimal prior engagement in such warfare except for limited indirect support to the Yemeni army in its operation against the Houthis in 2009-2010. In contrast, Emirati forces were more efficient in ground combat and organisational structure, particularly in southern Yemen, largely stemming from prior military engagements alongside Western militaries in operations such as Afghanistan (Knights, 2023). Despite access to a vast stockpile of precision-guided munitions replenished by the U.S., the Royal Saudi Air Force (RSAF) inflicted significant collateral damage, suggesting shortcomings in training and Rules of Engagement (ROE). Coalition airstrikes struck civilian targets on several occasions, resulting in considerable civilian casualties, including the bombing of a funeral hall in 2016, a school bus in a public market in 2018, and a wedding party in the same year. Under mounting international scrutiny, the coalition eventually conceded to such combat errors and reportedly launched investigations into the conduct of certain Saudi commanders.

The coalition became entangled in a protracted guerrilla warfare with the Houthis (Mutschler & Bales, 2024), a capable semi-state actor that, for roughly two decades, has received Iranian, Hezbollah, and Iraqi militia support in missile development, drone technology, and guerrilla-warfare training (United Nations Security Council, 2024). Using SCUD missiles looted from Yemen’s army and further external assistance, primarily from Iran, the group acquired a varied arsenal of ballistic and cruise missiles, armed and reconnaissance drones, and man-portable air-defence systems. As Knights (2018) observes, the Houthis “moved from small-arms ambushes to medium-range ballistic missiles in half a decade” (p.15). Their Iranian-derived ballistic missiles include the Qaher-1/M2 (250–400 km), Burkan-2H (1,000 km), Burkan-3 (1,200 km), Toofan (1,950 km), and the Palestine-2 hypersonic missile (2,150 km). Attack drones include: Qasef-1 and Qasef-2K (150 km), Sammad-1 (500 km), Sammad-2 (900 km), Sammad-3 (1,500 km), and Waid-2 (2,500 km) (Anderson, 2025; Hoffmann & Wright, 2022). Training by Iranian and allied operatives includes training in missile assembly, unmanned aerial vehicles (UAV) programming, and guerrilla tactics.

The coalition struggled to understand the nature of the Houthi tactics and strategy. Tactically, the Houthis adeptly employed ambushes and deployed small, agile units of three to five fighters to maximise mobility and minimise vulnerability to airstrikes (Knights, 2018, p.19). In contrast, coalition forces often operated in large, static formations vulnerable to missile attacks. For instance, in September 2015, a gathering of Emirati, Saudi and Bahraini soldiers near an ammunition depot in Marib was struck by a Houthi missile that killed more than 50 personnel. Similarly, in September 2019, three Saudi-backed Yemeni brigades were encircled by Houthi forces in Kitaf District, approximately 25 km from the Saudi border. The frequency of such incidents and the growing toll of collateral damage prompted self-reflection within the coalition. Brigadier Ahmed al-Asseri, the former coalition spokesperson, acknowledged these challenges, stating, “This is their first fight…you learn the hard way” (McDowall et al., 2016). Informed by time and earlier operational mistakes, the coalition seemed to adjust its conduct, with the final phase of operations reportedly proving effective in avoiding the bombing of civilians. Strategically, the Houthis adopted four approaches. (1) They mobilised through legitimacy and resistance narratives, presenting themselves as defenders of Yemeni sovereignty against foreign intervention and framing the war as both a national and religious struggle. These narratives countered the coalition’s collective punishment strategy aimed at turning public anger against the group. (2) They demonstrated resilience by withstanding sustained pressure and leveraging civilian suffering to bolster their position. (3) They employed an in-out offensive manipulation, fighting on local and border fronts while launching missile and drone attacks into Saudi Arabia and the UAE. (4) They tactically engaged in peace talks to buy time, reorganise, and consolidate their position.

Second, intelligence and coordination shortcomings were evident in both the identification of Houthi positions and capabilities and in the coordination with Yemeni ground forces. These deficiencies manifested across strategic, operational, and tactical levels. At the strategic level, the coalition struggled to anticipate the Houthi coup and detect Iran and Hezbollah’s supply routes to the Houthis. Moreover, the absence of pre-war military intelligence—despite the protracted Houthi insurgency in Sa’ada between 2004 and 2010—undermined the coalition’s preparedness for such a campaign. Consequently, the coalition became heavily reliant on externally sourced intelligence—particularly from the U.S., the UAE, and the Saudi-backed Yemeni government—to inform target selection. Intra-GCC tensions during the campaign raised concerns that sensitive information had been deliberately leaked or manipulated as a tool of political leverage within the broader regional dispute. At the operational level, the military operations in Yemen revealed intelligence dissonance between Saudi Arabia and the UAE, which was rooted in political and doctrinal differences. Some sources alleged that the UAE’s military intelligence apparatus had deliberately misled coalition forces, particularly the air forces, with the aim of targeting formations affiliated with the Islah party within the IRGY army (Hammoud, 2020). This context could explain the repeated airstrikes on these units, which were routinely attributed to ‘mistakes’ by the coalition. A particularly illustrative incident occurred in July 2015, when a coalition airstrike hit the ‘al-Abr’ military camp of IRGY in Hadramout, in the far east of the country, resulting in the deaths and injuries of approximately 100 soldiers, including senior officers. At the tactical level, coalition forces faced repeated failures in early warning and real-time intelligence, limiting their ability to anticipate and pre-empt Houthi offensives within Yemen and across the borders into Saudi Arabia and the UAE. Several airstrikes resulted in fratricide due to flawed target identification and inadequate coordination. In contrast, the Houthis—supported by Iranian and Hezbollah-linked counterintelligence units—employed information warfare and deception tactics to disrupt coalition operations. This included signals intelligence (SIGINT) collection via control of Yemen’s telecommunications infrastructure in Sana’a, enabling the interception of adversarial communications. They also reportedly manipulated targets and deployed disinformation to redirect coalition strikes towards rival factions and civilians, exploiting the aftermath for propaganda purposes (Gentry, 2019).

Third, the coalition—primarily Saudi Arabia and the UAE—faced organisational challenges in forming, integrating, and coordinating with a newly constituted Yemeni army composed of remnants of the pre-war military, tribal militias, and religious factions, each with distinct ideological outlooks and regional concentrations (Hokayem & Roberts, 2016). In addition to managing tribal dynamics, the Saudis and Emiratis were compelled to align with either Salafist forces or those affiliated with the MB. Despite Riyadh’s longstanding discomfort with the latter, it engaged them opportunistically for operational objectives. Due to a shortage of deployable infantry and the risks associated with ground operations, coalition members relied heavily on local forces. Although a Joint Operations Room was established by Saudi and Yemeni military elements, longstanding distrust—rooted in the post-Arab Spring political realignments and the intra-Gulf crisis (i.e., Saudi Arabia and the UAE versus Qatar)—contributed to fragmented agendas and geographically disconnected operations. This lack of cohesion, particularly with Islah-aligned forces in Taiz and Marib, led to communication breakdowns, incidents of friendly fire, and growing scepticism over the depth of Saudi–Emirati commitment to these allied formations (Al-Dahab, personal communication, February 15, 2024).

Reliability and Limitations of GCC’s Extra- Regional Security Partnerships

The Gulf Arab monarchies have long relied on extra-regional security partners, particularly the U.S., to manage external threats (Al-Shayji, 2014; Arafat, 2020; Saleh, 2020). Saudi Arabia, in particular, has maintained a strategic partnership with the U.S. since the onset of the Cold War, driven by shared concerns over international and regional communist movements. This alignment was formalised through the Nixon Doctrine, which positioned Saudi Arabia as a regional security pillar, and the Carter Doctrine, which committed the U.S. to protecting Gulf energy resources and allied regimes from communist expansion and Iranian revisionism. The alliance deepened during the rise of the Ba’athist regime in Iraq, especially following its invasion of Kuwait. In the wake of Iran’s regional expansion and the post-Arab Spring upheavals, Saudi Arabia and its GCC counterparts have intensified their demand for security guarantees from international allies, particularly the U.S. (Ulrichsen, 2025).

Alongside other Western powers, the U.S. provided logistical and intelligence support to the coalition. According to former U.S. Secretary of Defence James Mattis, this support constituted “limited U.S. military assistance to coalition forces engaging in operations in the legitimate exercise of self-defence” (Robbins et al., 2018). This included intelligence sharing, aerial refuelling, munitions supply, and the deployment of approximately 50 to 60 U.S. military personnel to coordinate and support coalition operations, with around 10 directly involved in the Saudi Air Force Operations Centre in Riyadh (McDowall et al., 2016). Although the Biden administration announced an end to offensive weapons sales to coalition members, defensive support, particularly missile defence systems, continued, exemplified by a $650 million sale to Saudi Arabia and a $65 million sale to the UAE (Lee et al., 2022). The UK and France also contributed substantial military assistance to the coalition, including the supply of heavy weaponry, training, technical expertise, and arms maintenance. Both countries deployed liaison officers to the operations centre in Riyadh to advise and monitor air operations. Additionally, the UK, through BAE Systems—its largest defence contractor—deployed Royal Air Force personnel to train and advise Saudi pilots (Merat, 2019).

However, Saudi expectations and U.S. responsiveness towards the coalition in Yemen diverged. Four key factors shaped Washington’s approach to the coalition. First, the U.S. ‘Asia Pivot’ and strategic retrenchment from the Middle East marked a shift towards offshore balancing, favouring indirect influence through partners over direct military involvement (Shield, 2018). Second, the doctrinal shifts in U.S. foreign policy from President Obama to President Trump (second term) further substantiate this argument. Third, U.S. policy on Yemen places emphasis on countering AQAP and safeguarding national interests in the region (Hartig & Hathaway, 2022). Since November 2023, the U.S. has led an international coalition, ‘Prosperity Guard’, in response to Houthi attacks in the Red Sea to explicitly protect the shipping routes and implicitly to prevent Houthi attacks against Israel and its regional interests. Fourth, the deterioration of the U.S.-Saudi relationship impacted the coalition in Yemen in several ways, including President Trump’s subdued response to the 2019 attack on the Abqaiq processing plant and Khurais oilfield and Biden’s initial stance, in which he sought to treat the kingdom as a pariah state (Munassar, 2023). Also, the Biden administration’s suspension of arms sales, revocation of the Houthis’ Foreign Terrorist Organisation (FTO) designation, previously enacted under Trump, and the 2021 withdrawal of Patriot missile defence systems from Saudi Arabia contributed to Saudi concerns over the credibility of U.S. security commitments. This sentiment was underscored by Prince Turki al-Faisal, former Saudi intelligence chief. In a CNBC interview, he commented ironically, “I think we need to be reassured about American commitment…That looks like, for example, not withdrawing Patriot missiles from Saudi Arabia at a time when Saudi Arabia is the victim of missile attacks and drone attacks — not just from Yemen, but from Iran” (CNBC, 2021).

After years of relative truce in the Yemen conflict, Trump’s 2025 redesignation of the Houthis as a terrorist group during his second term notably marks a reversal of the Biden-era delisting, reinforcing a hardline stance aligned with Saudi narratives. However, this approach has also been characterised by contradictions and strategic unpredictability. While Gulf leaders had high expectations for Trump’s return, especially following the strained Biden–MbS relationship, his administration has thus far delivered brutal continuities rather than strategic clarity (Lynch, 2025). Trump’s Riyadh speech in May 2025 lacked concrete policy declarations on Yemen, instead promoting arms sales and offering vague gestures towards diplomacy with Iran. This ambiguity has left Gulf leaders uncertain whether to expect confrontation or rapprochement. The resulting confusion underscores the GCC’s growing perception of Washington as an unreliable partner and has reinforced the ongoing recalibration of Gulf foreign policy, particularly Riyadh’s hedging strategies and economic diplomacy.

The perceived detachment of the U.S. from the regional and Saudi national interests (Wolf, 2020) has contributed to a growing trend towards foreign policy autonomy in Saudi Arabia and other GCC states. This autonomy is reflected in their increasing willingness to challenge established norms, including the long-standing ‘security for oil’ paradigm underpinning their alliances with Western powers (Saab, 2023). This shift is evident in a range of autonomous policy choices and strategic realignments.

First, the GCC states appear to be seeking a more diversified and flexible security architecture that better serves their specific needs and objectives. Saudi Arabia’s OPEC + decision to cut oil production, its refusal to join the U.S.-UK-led Red Sea coalition against the Houthis, and its growing links with China and Russia represent clear manifestations of this shift. The growing regional presence of China and Russia has contributed to a reconfiguration of the regional balance of power and has intensified great power competition (Bekkevold, 2019). In response, the GCC states began to adopt a more pragmatic approach to their foreign policy, seeking partnerships beyond traditional Western allies and engaging more actively in Global South blocs. Notably, both Saudi Arabia and the UAE were invited to join the BRICS in its 15^th summit in South Africa in 2023.

Such moves indicate that the GCC monarchies are adopting a calibrated foreign policy posture—characterised by strategic hedging—between established Western allies and emerging non-Western partners. For them, China presents an alternative model of governance focused on economic development rather than liberal norms (Fulton, 2019). Meanwhile, Russia—seeking to regain its Soviet-era influence and counter U.S. dominance—proposed security initiatives for the region, such as the ‘2019 Collective Security Concept for the Persian Gulf Area.’ In the Yemen conflict, Russia has maintained strategic neutrality, positioning itself as a potential mediator. Saudi Arabia, in particular, sees China and Russia—given their close ties with Iran—as potential actors to pressure Tehran and its proxies towards de-escalation and a negotiated settlement.

Second, the GCC states appear to be assuming greater responsibility for their own security by pursuing self-reliance through the formation of ad hoc military coalitions in response to threat contingencies (e.g., the coalition in Yemen) and by investing in the development of domestic defence industries. These efforts aim to reduce their reliance on external partners and enhance their capacity to manage security challenges autonomously.

Conclusion

In contrast to earlier interventions in countries such as Iraq and Afghanistan—where declassified data enabled investigations into intelligence and operational failures—comparable inquiries into the shortcomings of the Saudi-led Arab Coalition in Yemen remain limited and largely inaccessible. Unlike unilateral interventions, multinational ad hoc coalitions in counterinsurgency operations can yield modest success through joint efforts of burden-sharing, coordinated action, and mutual learning, thereby building institutional knowledge for future contingencies (Moller, 2022). Yet, they remain prone to failure due to political divisions, organisational fragmentation and operational flaws.

The Saudi-led coalition’s intervention in Yemen represents a critical case in the study of contemporary civil wars regarding the dynamics of external intervention, ad hoc coalition formation, and non-state actor resilience. For Saudi Arabia and the wider GCC region, the coalition intervention featured deep-rooted dilemmas in how Middle Eastern alliances perceive and respond to security threats. Politically, the intervention revealed a reluctance among regional leaders to address such threats through collective institutions and clearly defined objectives (Hlatky & Juneau, 2021). Organisationally, it underscored the fragility of security structures shaped by hesitant and often fragmented alliances. Operationally, it demonstrated the limitations of ad hoc coalitions in achieving strategic objectives due to incoherent planning and execution. At the same time, the intervention presents a compelling case for scholars of counterinsurgency and asymmetric warfare. The Houthis defy conventional insurgent models by evolving into a hybrid armed actor with both guerrilla tactics and quasi-state functions. Their resilience and adaptability in the face of a superior multinational force compel a reassessment of traditional counterinsurgency approaches. Furthermore, their rapid development of a sophisticated arsenal—including medium- and long-range ballistic missiles and drones with ranges exceeding 2,000 km—illustrates a striking acceleration in non-state actor military capabilities. The transnational scope of their operations, reflected in attacks on strategic infrastructure in Saudi Arabia, the UAE, and international shipping lanes in the Red Sea, and beyond, like Israel, underscores the evolving nature of asymmetric warfare and the complex security challenges it poses to regional and global actors alike.

To conclude, this case study underscores three interrelated lessons. Reliance on force alone internationalised the Yemeni war, weakened the country’s state structures and empowered its sub-state actors. The coalition’s fluid membership, divergent objectives, and operational shortcomings exposed the limitations of ad-hoc coalitions, informing the need for prior strategic consensus and security frameworks. Likewise, hesitant extra-regional partners like the U.S. inform the GCC states and the broader Middle East of the imperative of building treaty-based security alliances or, at a minimum, diversifying partnerships. These outcomes and lessons also matter well beyond the Yemeni case, extending to Libya, Syria, and Sudan, where fragmented interventions through coercive means and loose coalitions have internationalised existing civil wars and polarised local actors, giving rise to competing de facto authorities, rival ideological identities, and foreign patronage networks.