The Yemen–Horn of Africa Corridor: Houthi Expansion and the Gap in American Red Sea Strategy

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Earlier this month, U.S. Africa Command (AFRICOM) warned that Yemen’s Houthis are seeking to expand into Somalia, and that Houthi fighters or representatives may already be operating in the north of the country alongside al-Shabaab, al-Qaeda’s affiliate there. The warning followed the Houthis’ September seizure of roughly 115 kilometers of Yemen’s Red Sea coast, including the port of Mokha and Perim Island in the Bab al-Mandab, in an offensive guided by Revolutionary Guard advisers, and it came as a Saudi-backed counteroffensive moved to retake the strait.

Together, these two developments compound the threat that each poses. The Houthis now hold much of the Arabian side of the southern Red Sea, and since at least 2023 they have been building a network of clients, suppliers and smuggling routes on the African side of the Gulf of Aden. The network already moves weapons, fighters and technical know-how between Yemen and Somalia. Its next stage is operational, and its reach extends well beyond the Red Sea. An al-Shabaab armed and trained by the Houthis, and through them by Iran, gains the ability to threaten American forces and interests across East Africa, while the Houthis gain the means to watch shipping from the Somali coast and to press on the one Israeli foothold emerging on the African shore, at Berbera in Somaliland. Iran’s proxies now have proxies of their own, and advanced weapons and technical know-how can cascade from Iran through the Houthis to jihadist networks that lie beyond the control of the Revolutionary Guard.

This is ultimately a much larger threat than the Horn of Africa. The United States confronts this network through two combatant commands, a maritime counterterrorism doctrine that commits American force to protecting American ships, and a set of regional partners competing over their interests in the territory in question. But these new developments constitute a new matrix of threats that requires a shift in both strategic vision and threat assessment.

Yemen as a Relay Node of Jihad

The network now taking shape across the Gulf of Aden is the latest form of a pattern that has run through Yemen’s history for decades. A long coastline, a weak central government and a position between the Arabian Peninsula and the Horn of Africa have repeatedly made Yemen a relay station for militant movements, a place where ideas, money and weapons arrive from outside, where fighters are trained and organized, and from which capability is sent onward across the water. Each phase left behind routes, personal ties and channels of cooperation that the next inherited.

The first phase began with the war against the Soviet occupation of Afghanistan. Between 1984 and 1989, the Yemeni cleric Abdul Majid al-Zindani sent between 5,000 and 7,000 Arab volunteers, many of them Yemenis, for training in Pakistan and Afghanistan. When the war ended, many returned to a newly unified Yemen, where President Ali Abdullah Saleh used them as proxies against southern secessionists in the 1994 civil war. The state’s accommodation of these jihad veterans gave al-Qaeda its first operating ground in the region, with targets at sea and across the Gulf of Aden from the start. In December 1992, bombs exploded at two hotels in Aden where American troops stopped on their way to Somalia, and in October 2000 an al-Qaeda suicide boat struck the USS Cole in Aden harbor, killing 17 American sailors.

The second phase made Yemen a hub of jihad in its own right. In January 2009, the Saudi and Yemeni branches of al-Qaeda merged to form al-Qaeda in the Arabian Peninsula (AQAP), which within a year attempted to bomb a passenger jet over Detroit. AQAP also became the partner of Somalia’s al-Shabaab across the water. In April 2011, American forces captured Ahmed Abdulkadir Warsame, al-Shabaab’s emissary to AQAP, in the Gulf of Aden as he returned from Yemen, where he had received explosives training and brokered a deal for al-Shabaab to buy weapons directly from AQAP.

The third phase brought Iran. The Houthi movement grew out of a Zaydi revival whose leader, Hussein al-Houthi, took the Iranian revolution and Hezbollah as his models, and from 1994 the family sent dozens of students a year to seminaries in Qom, Iran, some of whom received paramilitary training from the Revolutionary Guard. By 2013, Iranian weapons were reaching Yemen by sea.

This history makes it clear that the Houthi–al-Shabaab network runs on a durable infrastructure and that doctrinal hostility between different Muslim sects has never been a dependable barrier in Yemen. Earlier crossings of the sectarian line were tactical, as when Saleh, himself a Zaydi Shia, turned Sunni jihadists against the south, or when the Houthis made their truce with AQAP.

AQAP and the Triangle Across the Gulf of Aden

The Houthi relationship with al-Shabaab runs through AQAP, with which the Houthis reached an accommodation first. The result is a three-sided system in which the Houthis supply, AQAP brokers and operates in southern Yemen, and al-Shabaab buys on the African side.

The UN Monitoring Team that tracks al-Qaeda and the Islamic State reported in February 2026 that AQAP acquires weapons from the Houthis, among other sources, and cited a member state’s account that the Houthis paid AQAP some 250,000 Saudi riyals, about $65,000, as a reward for an attack in June 2025, and that Houthi elements joined AQAP in joint operational planning in Abyan that August. The same report recorded a member state’s account of meetings in Somalia in October 2025 aimed at forming a joint unit of Houthis, AQAP and al-Shabaab. It assessed the Houthis’ direct collaboration with al-Shabaab as limited and transactional, focused on training and weapons acquisition. Read together with the UN Panel of Experts on Yemen’s finding that the Houthis provide training and medical care to AQAP operatives in Houthi-held areas, the picture is a triangle whose densest ties run between the Houthis and AQAP, and whose African extension is now being organized.

The Houthi Supply Network in Somalia

Al-Shabaab, which has fought the Somali government for nearly two decades, is the wealthiest of al-Qaeda’s affiliates, raising at least $100 million a year through the extortion and taxation it imposes on the territory it holds in southern and central Somalia, and it operates along a coastline that no government effectively controls. Yet it has no military industry of its own. Its arsenal has consisted largely of small arms, improvised explosives and commercial drones bought or captured locally, and it has had neither the weapons that would allow it to contest the air nor the technical knowledge to build, modify and maintain more sophisticated systems.

The Houthis possess the capability al-Shabaab lacks, having built over the past decade, through years of Revolutionary Guard and Hezbollah instruction, an arms industry that assembles drones, adapts missiles and manufactures explosives, and they now sell the knowledge behind it. Designated a Foreign Terrorist Organization since March 2025, and with Iran’s ports under an American blockade, the Houthis need hard currency from outside Yemen. The commander of U.S. Central Command, Admiral Brad Cooper, says Iran-backed groups must now send money back to the Revolutionary Guard. They also need smuggling routes that bypass the interdiction of their own coast, and Somalia, which the UN Panel of Experts on Yemen found increasingly serving as a transit hub for weapons bound for the Houthis, provides both.

Both UN expert panels have documented the exchange. The Yemen panel reported in October 2025 that the Houthis were transferring weapons to al-Shabaab, that two Houthi military engineers had trained its members in making explosives, adapting drones and maintaining weapons, and that the Houthis controlled the smuggling linking al-Shabaab, AQAP and regional networks. A month later, the Somalia panel reported that four groups of 30 al-Shabaab fighters traveled to Yemen for training, one of them for two months near Hudaydah, the Houthis’ principal Red Sea port and military stronghold, where instruction of that kind runs through Houthi facilities and security. The Wall Street Journal has reported that at least 100 al-Shabaab fighters have made the trip, one group spending three months this year learning drone assembly.

The effects of this cooperation are already apparent. Al-Shabaab has used commercial drones for reconnaissance for years, but in 2024 Puntland security forces intercepted five commercial drones modified to carry explosives, which officials believed the Houthis had shipped through the port of Bosaso. That capability binds al-Shabaab to the Houthis, because the components, replacement parts and technical knowledge needed to keep armed drones in the air arrive from Yemen. The same capability makes al-Shabaab worth more to the Houthis, since a group able to strike on its own can carry Houthi purposes onto the African shore, from the surveillance of shipping in the Gulf of Aden to the campaign against any Israeli presence at Berbera.

Surveillance, Recruitment, and the American Presence

Access to the African coast gives the Houthis three strategic assets beyond revenue: the ability to watch shipping from both sides of the Gulf of Aden, a recruiting ground outside Yemen, and a means of challenging the Israeli presence taking shape in Somaliland. Somalia also offers both movements a further prize, which they share with al-Qaeda’s founding generation: the prospect of driving the United States out of another corner of the Muslim world. In his 1996 declaration of war on the United States, Osama bin Laden praised the 1993 Mogadishu firefight, remembered in the West as Black Hawk Down, after which the United States “left the area carrying disappointment, humiliation, defeat and your dead with you,” and the thinning of American surveillance over Somalia now offers the Houthis and al-Shabaab the prospect of a repetition. Berbera and the American presence in the Horn are the two objectives the Houthis and al-Shabaab share on their own account.

The Houthis seek al-Shabaab’s help in deploying radar coverage of the shipping lanes from the Somali coast, according to an intelligence briefing reviewed by the Wall Street Journal, and Matt Bryden, a former coordinator of the UN monitoring group on Somalia, told the Financial Times that such equipment is already installed. The Houthis also seek permission to recruit in Somalia and the ability to launch attacks from Somali territory. Radar on the Somali shore would extend Houthi targeting across the full width of the Gulf of Aden.

Berbera turns this network into a front against Israel. Israel recognized Somaliland in December 2025, and Abdul Malik al-Houthi responded by declaring any Israeli presence there a military target. By March, Israel was seeking a military base at Berbera. Al-Shabaab, for its own reasons, has declared that it will oppose any Israeli use of Somaliland. The two movements therefore converge on the same objective. In June, a four-member Houthi delegation crossed the Gulf of Aden to Jilib, al-Shabaab’s stronghold in southern Somalia, where discussions included countering Israeli activity at Berbera, according to the Journal.

The implication for Israel is clear. Any Israeli military installation at Berbera would sit within reach of Houthi missiles from the north and al-Shabaab’s networks from the south and east, and the Houthis are building the surveillance and liaison needed to link the two.

Permissive Conditions on the Arabian Shore

While building on the African shore, the Houthis are pressing their advantage against Saudi Arabia on the Arabian one. Since July, the Houthis have enforced a blockade on Saudi oil carriers in Bab al-Mandab, which they present as retaliation for the Saudi blockade of Houthi-held Yemen. On September 10, drones that the Saudi foreign ministry said came from Iraq struck the East-West pipeline, which carries Saudi crude to the Red Sea, and Riyadh then shut down the line. On September 19 the Houthis fired a ballistic missile at Riyadh, and Saudi Arabia, running low on interceptors, asked France, Britain, Pakistan and Egypt for air defense support.

Washington’s choices have given the Houthis room to maneuver. Crown Prince Mohammed bin Salman asked President Donald Trump for military support; Washington offered intelligence and targeting assistance, and U.S. officials said they would refrain from military action provided the Houthis did not disrupt non-Saudi traffic in the Red Sea. Strike options prepared by U.S. Central Command (CENTCOM) were not carried out. In Muscat in mid-September, Houthi representatives told U.S. officials they would not attack American or Israeli ships or other commercial vessels, with the exception of Saudi ones. The May 2026 U.S. counterterrorism strategy ties the prospect of decisive American military action in Yemen specifically to the endangerment of American ships.

Washington continues to provide Riyadh with intelligence and targeting support, yet the cumulative effect of its choices is permissive. The condition Washington attached to its restraint coincides with the terms the Houthis offered in Muscat, which leaves Saudi shipping outside the protection of American power. The Houthis can escalate against Saudi Arabia, defend their gains on the Yemeni coast and develop their Somali network at little risk of American retaliation, and every month in which the situation remains unchanged gives the African side of the network time to mature.

From Regional Network to International Jihad

International jihadism lost much of its reach after the fall of the Islamic State’s caliphate, in part because the Sunni jihadist movements were cut off from havens, money and advanced weapons. The Houthi network now offers all three to al-Qaeda’s two most capable affiliates, with Iran behind it. Tehran’s accommodation of al-Qaeda has until now taken the form of shelter, and the State Department has assessed that al-Qaeda’s de facto leader, Saif al-Adel, is based in Iran. Through the Houthis, that accommodation has become supply. The capabilities crossing the Gulf of Aden, from drone assembly and explosives manufacture to the air defense al-Shabaab has requested, have belonged until now to states and to Iran’s own proxies.

Both recipients have long sought to strike beyond their region. AQAP, which tried to bring down an airliner over Detroit in 2009, claimed the 2015 Charlie Hebdo massacre in Paris, and in 2024 a Kenyan operative was convicted in New York of plotting a hijacking attack on an American city on behalf of al-Shabaab after training as a pilot in the Philippines. Houthi technology joined to that intent turns a regional insurgent network into a threat to Western aviation and to the American homeland. The fighters trained in Saada and Hudaydah will also return home, carrying their skills to Somalia, Kenya and the Somali diaspora.

This threat is maturing as American counterterrorism capacity in the region contracts. The U.S.-led coalition left Iraq at the end of September, Central Command is absorbed by the blockade of Iran, and drone losses are thinning surveillance over Somalia. Yemen has shown before what follows such gaps: when the Yemeni state collapsed in 2015, AQAP seized Mukalla and governed it for more than a year.

The Seam in American Strategy

The United States already possesses most of the instruments needed to contest this network; it lacks a single operational picture and the policy to use it. The network spans the boundary between two combatant commands: AFRICOM, which is responsible for operations on the continent, sees the Somali side, while CENTCOM, absorbed in enforcing the naval blockade of Iran, carries responsibility for Yemen.

The partners Washington needs are deeply divided over their interests in the region. Saudi pressure forced the UAE-backed southern separatists in Yemen to disband and the last Emirati troops to withdraw, and Riyadh has accused Abu Dhabi of using Somaliland to move a separatist leader out of Yemen. The two governments began to repair the rift in late September, when Sheikh Mansour bin Zayed Al Nahyan met Crown Prince Mohammed bin Salman in Riyadh in their first high-level meeting since it opened, but the repair is incomplete. The UAE operates Berbera port and maintains an expanded military base nearby. Saudi Arabia, the UAE, Egypt and Israel each hold different positions on Berbera, the one place where Houthi and al-Shabaab objectives meet.

The policy problem therefore extends well beyond the protection of commercial vessels. American strategic thinking is still organized around boundaries that Yemen’s history shows to be porous: sectarian enemies expected to check one another, an Iran held answerable for its proxies, and a region whose theaters fit the map of combatant commands.

The task, then, is to prevent the consolidation of a network spanning the Gulf of Aden in which the Houthis provide Iranian-derived technology and training, AQAP supplies the connective tissue in southern Yemen, and al-Shabaab offers territory, manpower and access to the African shore. As that network matures, the challenge facing the United States moves from episodic attacks on shipping toward a standing insurgent infrastructure on both sides of one of the world’s most important maritime chokepoints, with Iranian capability at its core and American, Saudi and Israeli interests within its reach.

Recommendations

First, the United States should treat passage through Bab al-Mandab and Hormuz as one principle and refuse to negotiate it flag by flag. An American exemption obtained in Oman only confirms the Houthis’ claim to administer access to the Red Sea.

Second, Washington should secure access at Berbera while deferring recognition of Somaliland. Camp Lemonnier lies about 80 miles from Perim, in a Djibouti that avoids confronting the Houthis and hosts a Chinese base, and American surveillance over Somalia is thinning as drone losses mount. Berbera offers a deep-water port and one of Africa’s longest runways, which Hargeisa has offered to the United States, alongside an Emirati facility reportedly built for American and Israeli use. Recognition would add little to that access and much to the strain with Riyadh and Cairo at the moment their cooperation matters most. A Taiwan-style relationship serves American purposes better: contingency access, an upgraded American presence in Hargeisa and support for Somaliland’s coast guard, with recognition held in reserve.

Third, the United States should organize Red Sea cooperation so that it does not depend on the state of relations between Riyadh and Abu Dhabi. Within a single year the two have moved from open confrontation in Yemen to tentative reconciliation talks. Washington should work through separate bilateral channels: with Saudi Arabia on the Yemeni coast, where its counteroffensive is under way, and with the UAE on the African shore, where its position at Berbera gives it the closest view of the network. Israel should extend the intelligence support it already provides Riyadh through CENTCOM. American channels would carry warning and targeting data among all three, so that cooperation survives a renewed rift and no government must endorse another’s policy on Somaliland. Washington should also use those channels to keep Saudi and Emirati clients off each other’s ground, since the contest between their Yemeni clients fractured the anti-Houthi coalition before the September offensive.

Fourth, Washington should direct Treasury action and intelligence collection at the Houthi–AQAP–al-Shabaab triangle as one system. The organizations are already designated, so the leverage lies where the network’s money enters the formal financial system: the Gulf-based front companies, exchange houses and money-transfer firms that settle its payments, and the businesses that supply its smugglers with fuel, engines and boats, all of which depend on access to the dollar. Collection should follow the triangle as a whole, drawing on the surveillance Berbera makes possible, before the joint unit that the UN Monitoring Team is reported to be planning becomes a command on the African shore.

Fifth, the United States should protect its counterterrorism coverage of Yemen and Somalia from the demands of other theaters and prepare now for the fighters the network is training. Surveillance and collection over both countries should be shielded from reallocation, since terrorist networks grow fastest when American attention lapses, as AQAP’s year in Mukalla showed. Washington should also build screening and intelligence-sharing arrangements with Kenya, Ethiopia, and European governments on individuals who have trained with the Houthis, so that their return to Somalia, East Africa, and the diaspora is tracked before it produces the kind of plot al-Shabaab has already attempted against the United States.

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