هذا التقرير متاح أيضًا بـ العربية
Saudi Arabia entered the war in Yemen in 2015 with overwhelming military superiority, an advanced arsenal of fighter jets, missiles and air defence systems, and leadership of a regional coalition seeking to retake the capital, Sanaa, and end Houthi control over state institutions. But after more than 11 years of military operations, the group remains entrenched in its main strongholds and has developed missile capabilities that can threaten vital facilities inside the kingdom.
The Saudi campaign’s failure stems from a misreading of the war and a heavy reliance on air strikes against a group experienced in mountain warfare and attritional conflict. The Houthis also drew on the Yemeni army’s arsenal and Iranian support to build a growing military force, while divisions and Saudi-Emirati rivalry weakened the Yemeni forces opposing them and hampered efforts to retake Houthi-held areas.
With large-scale clashes resuming in 2026, the cost of any new Saudi attempt to secure a military victory has risen as the Houthis have expanded their attacks on oil facilities, airports and economic infrastructure. Retaking Sanaa would also require an extensive ground campaign, alongside security and political arrangements that would prevent the group from returning to the battlefield. Why have the Houthis not been defeated after so many years, and what still prevents Riyadh from winning the war militarily?
Misreading the war and relying too heavily on air power
The Saudi campaign’s problems began with its initial assessment of the war. Riyadh entered the conflict on 26 March 2015 expecting a swift victory through intensive air strikes that would pave the way for forces loyal to the Yemeni government to retake Sanaa. The Houthis had seized the capital in September 2014 before expanding south with support from military units loyal to former Yemeni president Ali Abdullah Saleh.
Saudi Arabia enjoyed overwhelming superiority in fighter jets, long-range munitions, reconnaissance and military logistics. Its military spending reflected that advantage, reaching about $83.2 billion in 2025, according to estimates published by the Stockholm International Peace Research Institute on 27 April 2026. This placed the kingdom eighth worldwide and first in the Middle East.
The coalition made extensive use of this superiority. The Yemen Data Project, an independent initiative that monitors air operations, documented 25,054 air strikes by the Saudi- and UAE-led coalition between March 2015 and March 2022.
But Yemen’s geography favoured the Houthis’ defence, particularly in the northern and western highlands around Sanaa and Saada, with their steep mountain ranges, valleys and narrow passes. This terrain lends itself to ambushes and fortified positions, provides cover for weapons depots and allows fighters to move in small groups that are difficult to detect and target.
Since 2004, the Houthis have gained extensive experience in guerrilla warfare. They rely on small units bound by social and tribal ties, using ambushes, sniping, mines and local knowledge of mountain passes to make their positions difficult for attacking forces to detect and capture.
In a study published by Cambridge University Press in late 2021, military researcher Ralph Shield concluded that Saudi air power had helped impede Houthi advances and prevent the group from taking control of all of Yemen. He found that it achieved better results when supporting ground forces, while strategies involving bombing, blockade and the targeting of leaders faced major difficulties in subduing the group and forcing it to surrender.
The limits of that superiority became clear in the battle of Marib in 2021, when the Houthis launched a major offensive on the province east of Sanaa, the internationally recognised government’s most prominent stronghold in northern Yemen. The coalition deployed military reinforcements and intensified air strikes to support government forces, helping to slow the Houthi advance. Fighting nevertheless continued for months without a decisive outcome.
In January 2022, the Giants Brigades, Yemeni military formations backed by the UAE, made rapid gains in Shabwa province and Marib’s Harib district. They benefited from training, weapons, organisation and air support, underscoring the importance of ground forces capable of capitalising on air strikes to seize and hold positions.
Targeting and intelligence failures further complicated the campaign. A Reuters investigation published on 19 April 2016 pointed to excessive reliance, at some stages of the operations, on information supplied by local Yemeni parties.
The investigation cited a 2010 US diplomatic cable documenting the cancellation of a Saudi strike after it emerged that the target supplied by the Yemeni authorities was the headquarters of a military commander at odds with former president Ali Abdullah Saleh. The incident highlighted the risks of relying on intelligence from parties involved in local conflicts.
Air strikes that caused civilian casualties also drew mounting international criticism. In September 2021, the UN Human Rights Council’s Group of Eminent International and Regional Experts announced that, since 2018, it had investigated about 30 coalition strikes that caused civilian deaths and injuries. In specific cases, it found failures concerning distinction, proportionality and the precautions required during attacks. The coalition rejected some of those findings and criticised the investigations’ methodology.
Political and human rights pressure also helped change the level of western support for the operations. The US halted aerial refuelling for coalition aircraft in 2018. In February 2021, the administration of former US president Joe Biden announced an end to support for offensive operations linked to the war. Restrictions on offensive weapons sales to Saudi Arabia were subsequently lifted in 2024.
The Houthis’ growing strength and ability to absorb losses
The Houthis withstood the Saudi campaign thanks to their arsenal of heavy weapons, military expertise and institutions for financing and recruitment. Access to Yemeni army weapons, their alliance with former president Ali Abdullah Saleh and, later, Iranian support in developing missiles and drones strengthened their ability to absorb losses and continue fighting.
After the Houthis took control of Sanaa in 2014, their alliance with Saleh gave them access to army stockpiles and military systems, as well as the expertise of officers, engineers and technicians in the armed forces. Security and military units loyal to the former president continued fighting alongside them during the early years of the Saudi intervention.
The weapons seized by the Houthis included tanks, artillery, ballistic missiles and air defence systems. In June 2015, forces allied with them launched a Scud ballistic missile towards Saudi Arabia. The Houthis’ relationship with Saleh later unravelled and ended with his killing in December 2017. By then, the group had already absorbed a large share of the military and security capabilities associated with him.
Iranian support subsequently helped the Houthis develop their weaponry. Reports issued by the US Defense Intelligence Agency in 2024 documented that support, identifying technical similarities between Iranian systems and the missiles and drones used by the group, as well as components and weapons seized in shipments bound for Yemen.
Iranian assistance included the transfer of equipment, technology and expertise for assembling and operating missiles and drones, alongside training and the development of targeting, navigation and air defence capabilities. This helped the Houthis extend the range of their attacks and deploy more sophisticated systems.
On 15 October 2026, Andreas Krieg, a professor of security studies at King’s College London, explained that members of Iran’s Revolutionary Guard and Lebanon’s Hezbollah had helped the Houthis acquire technical knowledge of missiles and drones. He said former Yemeni military engineers and locally trained technicians had also helped develop this expertise within the group.
An October 2026 field study by the UK-based Conflict Armament Research also confirmed that the Houthis were seeking to manufacture parts for medium-range ballistic missiles inspired by Iran’s Kheibar Shekan system. Researchers examined components, testing tools and materials linked to solid-fuel engines seized in shipments bound for the group. Shipping documents identified a Chinese supplier of some components, indicating that supply networks were expanding.
Alongside developing their weaponry, the Houthis expanded their ranks. A 2024 report by the UN Panel of Experts estimated that the number of fighters affiliated with the group had risen from about 30,000 in 2015 to 350,000.
The UN also documented the use of schools, summer centres, incentives and social pressure to recruit children and young people. Its 2025 annual report on children and armed conflict verified the recruitment and use of 127 children by the Houthis, warning that restrictions on access to some areas hindered efforts to document all cases.
The Houthis used their control over state institutions to collect taxes, customs duties, fees and levies, alongside revenues from the telecommunications, fuel and commercial sectors. In its 2024 report, the UN Panel of Experts estimated that the revenues the group collected and controlled during 2023 totalled about 3.392 trillion Yemeni rials, or about $6.4 billion.
Those revenues included about 300 billion rials from land collection points. The panel said some of those proceeds were used to pay fighters’ salaries and finance military activities.
A study published by the Sana’a Center for Strategic Studies in February 2026 said the group continued to impose taxes and fees and control assets and economic sectors to bolster its resources, while the internationally recognised government faced declining revenues, disrupted oil exports and divided financial institutions.
Divisions among Yemeni forces opposing the Houthis
The existence of numerous Yemeni factions opposed to the Houthis, combined with conflicting Saudi and Emirati interests, weakened the ground forces on which Riyadh relied in the war. These forces were split into formations with different leaders, loyalties and political objectives. Some were also preoccupied with internal struggles over influence and economically important areas.
This camp included government army units, tribal forces and local formations in Marib, alongside the UAE-backed Giants Brigades and the National Resistance Forces led by Tariq Saleh, a Presidential Leadership Council member and nephew of former Yemeni president Ali Abdullah Saleh. It also included the Southern Transitional Council, which advocated South Yemen’s secession.
Saudi Arabia sought to support the internationally recognised government and preserve a unified Yemeni state that would secure its southern border. The UAE, meanwhile, backed southern and local formations with different political and military goals, particularly over control of Aden, the ports and the western coast, and the future of South Yemen.
The disagreements escalated into direct confrontation in August 2019, when the UAE-backed Southern Transitional Council seized Aden, the temporary seat of the Saudi-backed government. Fighting then broke out between the two sides, deepening divisions within the coalition and weakening efforts to coordinate military operations.
A February 2021 study by the US research institution RAND concluded that local political and economic grievances, alongside divisions among the Houthis’ opponents, had hindered efforts to build a stable coalition and helped weaken government institutions and forces.
Those disputes worsened in late 2025, when UAE-backed Southern Transitional Council forces expanded into the eastern Yemeni provinces of Hadramout and Al-Mahra. Saudi-backed forces then intervened to retake those areas, leading to an open political and military confrontation between Riyadh and Abu Dhabi.
As the UAE announced the withdrawal of its remaining forces from Yemen in December 2025, Saudi Arabia began reorganising forces and government institutions in the south and trying to absorb formations that had previously received Emirati funding.
A Reuters investigation published on 5 February 2026, citing officials and informed sources, revealed that Riyadh had allocated nearly $3 billion that year to pay salaries, support projects and fund southern forces. The aim was to unify the factions and strengthen the authority of the internationally recognised government.
But weaknesses in military coordination resurfaced in September 2026, when the Houthis launched a major offensive on Yemen’s western coast. They seized Mokha and areas and islands near the Bab el-Mandeb Strait, exposing shortcomings in the preparedness, command and intelligence of Saudi-backed forces.
The attack revealed a misreading of the scale of Houthi mobilisation and preparations, alongside weak coordination within the command structure that took shape after the Emirati role receded. A Reuters investigation quoted a diplomat who estimated that the group had mobilised about 100,000 fighters without its preparations being adequately detected.
Neil Quilliam, a Gulf affairs specialist at the UK-based Chatham House, described what happened as a clear intelligence failure. Yemeni researcher Farea al-Muslimi, who specialises in Yemen and Gulf affairs, said the Saudis were caught off guard by the attack, which ended with forces allied with Riyadh withdrawing and leaving behind equipment and weapons that the Houthis seized.
Al-Muslimi and Sanam Vakil, director of Chatham House’s Middle East and North Africa Programme, argued that Saudi-Emirati rivalry had weakened the forces opposing the Houthis. Internal disputes, weak governance and corruption allegations, they said, had also undermined the effectiveness of Yemen’s Presidential Leadership Council, established in 2022, and hindered efforts to build institutions capable of administering areas outside Houthi control.
Threats to Saudi Arabia’s heartland and the rising cost of war
The development of Houthi missiles and drones has raised the cost of Saudi military operations by enabling the group to target oil facilities, airports and economic infrastructure inside the kingdom. This has forced Riyadh to devote increasing resources to air defence and infrastructure protection, while making economic and security risks a factor in planning any large-scale offensive inside Yemen.
The threat became especially clear in March 2022, when the Houthis targeted Saudi Aramco facilities, including a fuel storage facility in Jeddah where a major fire broke out. They also said they had attacked other oil sites.
The importance of halting cross-border attacks was reflected in the UN-brokered truce that began on 2 April 2022, according to a study published two months later by the Armed Conflict Location & Event Data Project, an international initiative specialising in conflict documentation. It said the previous year had seen more than 40 events involving coalition air strikes each week, alongside about four Houthi missile and drone attacks on Saudi Arabia a week.
Coalition air strikes and Houthi cross-border attacks almost ceased during the first two months of the truce. Riyadh subsequently moved gradually towards direct negotiations with the group, receiving a Houthi delegation in September 2023 to discuss a ceasefire, salaries, ports, Sanaa airport and security arrangements.
Over the following years, the Houthis gained further experience in long-range attacks. Since the start of the Israeli assault on the Gaza Strip in October 2023, they have intensified attacks on Red Sea shipping and launched missiles and drones towards “Israel,” prompting the US and Britain to begin striking their positions in January 2024.
The group also came under Israeli strikes targeting military sites and facilities inside Yemen. In May 2025, the Houthis and the US reached a separate agreement to halt attacks on each other, while Yemen’s crisis continued without a comprehensive political settlement.
Regional tensions escalated with the outbreak of the broad US-Israeli confrontation with Iran in February 2026. Houthi attacks on Saudi Arabia resumed in July and expanded in September and October, as the group threatened shipping through the Bab el-Mandeb Strait, one of the Red Sea’s most important maritime corridors for trade and oil exports.
In September 2026, informed Iranian sources told Reuters that Riyadh had asked China to use its influence with Tehran to pressure the Houthis to stop their attacks, after Pakistan conveyed Saudi warnings to Tehran. This indicated that the kingdom was seeking to contain the threat through regional diplomacy.
The attacks escalated further in October, when the Houthis targeted Saudi airports and oil facilities, including King Khalid International Airport in Riyadh. One attack killed 13 people and wounded about 300 others, according to the toll announced at the time. An attack on Aramco’s headquarters in the eastern city of Dhahran that month sparked a fire and damaged parts of the building.
Major General Turki al-Maliki, spokesman for the Saudi-led coalition, said the Houthis had tried to attack King Khalid Airport 20 times that month and that the series of attacks on the kingdom’s facilities had killed people and injured hundreds. He also said 127 weapons depots in Yemen’s mountainous areas had been destroyed, along with launch platforms linked to the group.
The attacks exposed challenges facing Saudi air defences, given the kingdom’s vast size and widely dispersed vital facilities, as well as the depletion of US-made interceptor missile stockpiles during the confrontation with Iran. These factors made complex and repeated attacks more difficult to counter.
Farzan Sabet, a Middle East researcher at the Geneva Graduate Institute, explained that the kingdom faced difficulties in providing an integrated air defence network covering all sensitive sites. He noted that the level of coordination between surveillance, warning and interception systems posed an additional challenge for Saudi defences.
The escalation also affected air traffic and economic activity. International airlines were forced to suspend or reroute flights, while a summit between the European Union and the Gulf Cooperation Council scheduled for 24 October 2026 in Riyadh was postponed because of security concerns and travel disruption.
The difficulty of ending the insurgency after retaking Sanaa
Saudi Arabia faces another obstacle: the difficulty of defeating the Houthis permanently, even if they lose Sanaa and the main cities. The group’s mountain strongholds, tribal and military networks, and past experience would allow it to return to guerrilla warfare. Holding recaptured areas, meanwhile, requires security and administrative institutions capable of governing and preventing renewed fighting.
The Houthis fought six wars against the Yemeni state between 2004 and 2010, four years before they seized Sanaa. Throughout that period, they maintained an armed presence despite repeated military campaigns, benefiting from the mountainous terrain of Saada and the surrounding areas.
In a 2020 RAND study titled “Could the Houthis Become the Next Hezbollah?,” researchers examined the group’s prospects for survival if it lost some of the territory under its control. These included retreating to its northern strongholds and rebuilding its military capabilities, scenarios rooted in the movement’s history and organisational structure.
Large-scale ground operations also pose major humanitarian and political challenges, especially in densely populated cities and sensitive economic sites. This was evident during the 2018 battle for Hodeidah, when the coalition launched a ground, air and naval offensive to seize the city and its Red Sea port.
At the time, the UN warned that a major battle to capture the port, a vital route for food imports and humanitarian aid to northern Yemen, could worsen famine, with about 8.4 million Yemenis at risk of severe hunger. This helped intensify international pressure to halt the offensive.
In July 2018, the UAE announced a temporary halt to its offensive operations to allow mediation. The Stockholm Agreement followed in December, halting the assault on the city as part of arrangements to de-escalate the conflict.
The humanitarian risks are resurfacing with the current escalation. Aid organisations reported in October 2026 that the new fighting had disrupted assistance to about 800,000 people and displaced more than 200,000 in the preceding weeks, while hospitals in combat areas faced shortages of medicine and basic supplies.
Recent Saudi military plans show the scale of the forces needed for any attempt to retake Houthi-held areas. A Reuters investigation published on 2 October 2026, citing six officials and informed sources from the region and the West, revealed that Riyadh was considering a ground campaign led by Yemeni forces with air and intelligence support. More than 100,000 fighters could be mobilised, depending on the scope of the assault.
The options under consideration included a limited operation to retake areas around Bab el-Mandeb and the western coast, or a broader offensive on simultaneous fronts in Al Bayda, Marib, Taiz and Al Jawf, in an attempt to put Houthi forces under pressure across several fronts and recapture strategic positions.
On 4 October 2026, Rashad al-Alimi, chairman of Yemen’s Presidential Leadership Council, announced the launch of military operations to retake Houthi-controlled areas. But the group continued to attack on different fronts, including Taiz and Aden. In Aden, it targeted Al-Maashiq Presidential Palace with missiles and drones, killing five people and wounding 16 others.
These developments coincided with Saudi efforts to secure external military support to bolster its defences and the capabilities of allied forces. A western official told Reuters that the US had provided intelligence and advisory assistance, while Pakistan and Turkey had contributed military equipment and expertise.
On 18 October, Egypt announced that it was ready to provide defensive military support to the kingdom. Egyptian President Abdel Fattah el-Sissi called for an urgent parliamentary session to consider that support.
Beyond the demands of military operations, Riyadh faces the question of how to govern any recaptured areas. Controlling Sanaa and other cities requires government and security institutions capable of controlling weapons, paying salaries and providing services. It also requires political arrangements with tribes and rival factions over the distribution of power and resources and the future relationship between northern and southern Yemen.
In their analysis for Chatham House, Sanam Vakil and Farea al-Muslimi argued that continued military pressure without a coherent political strategy risks recreating the conditions that allowed the Houthis to consolidate their control. A successful, lasting settlement, they said, depends on reforming Yemeni government institutions and reaching an understanding among Gulf states on the country’s future.
More than 11 years after the launch of Operation Decisive Storm, Saudi Arabia’s challenge is to meet military and political objectives simultaneously: retaking Houthi-controlled areas, protecting its own territory and economic facilities, and building a Yemeni authority capable of administering recaptured areas. The years of war have shown that superior firepower alone has not been enough to achieve those goals.