Dagger at the Red Sea: Charting the rise of the Houthis

Experts and officials describe how the once-obscure militia obtained a vast arsenal and disrupted one of the world's key trade routes

Pro-Houthi forces march during a military parade in Sanaa, Yemen in 2022. EPA

In a four-part series, The National reflects on a decade of war in Yemen, uncovering 10 years of conflict that has torn apart families, lives and livelihoods. The first and second parts can be found here and here

Ten years ago today, Yemen’s clan-based Houthi movement stormed key parts of the country’s capital Sanaa, after weeks of clashes and more than two decades of political turmoil.

It stunned observers around the Middle East – as shocking as the fall of Mosul and much of northern Iraq to ISIS only three months earlier. With global attention focused on ISIS’s spread across Syria and Iraq, few realised the full implications of the Iran-backed group’s advance towards the Red Sea coast.

In little more than a month, the Houthis were positioned to blockade the waterway, a transit point for about 30 per cent of shipping container trade globally. With local forces, a 2015 UAE-led “light footprint” effort stemmed the Houthi advance at the vital port of Aden – a significant achievement – but soon, the group was positioned to hold a dagger at one of the world’s trade chokepoints.

The Rubymar cargo ship partly submerged off the coast of Yemen after being hit by a Houthi missile in the Red Sea. AFP

While the Houthis dismissed accusations that this was their plan, experts say the blockade was years in the making, following a steady supply of Iranian arms and advisers. The blockade, which has already cost Egypt billions in Suez Canal revenue and worsened global inflation due to rising shipping costs, could have an impact lasting years longer than the Gaza war, one maritime expert tells The National.

Salvatore Mercogliano, a historian of global shipping at Campbell University, North Carolina, has taught US merchant sailors and says western powers were slow to wake up to the threat.

“The Red Sea had its moments in the past. You go back to 1984 [when] the Libyans mined the Red Sea, so there was always potential for this scenario to be reprised. What got me was, very quietly, the US Fifth Fleet stood up this combined Task Force 153 ... you don't stand one of those things up unless you know something's up or about to happen,” he says.

A helicopter lands on the guided missile destroyer USS Laboon in the Red Sea. AP

The move, partially in response to deteriorating relations between the US and the Houthis’ key backer Iran, followed at least 40 Houthi attacks on ships during the country’s civil war and in the years following several stop-start peace deals.

The Houthis say their Red Sea blockade is in solidarity with Palestinians, under heavy Israeli bombardment in Gaza that has killed more than 41,200 people.

A Houthi official, speaking to The National, characterised the Red Sea blockade as the “supporting battle for Al Aqsa Flood [Hamas’s October 7 attack on Israel] which we have named the Promised Conquest Battle and the Holy Jihad," as a "new and exceptional battle that has taken on a different dimension".

"There is a maritime aspect to this, which has necessitated the high activation of naval forces," he explains.

Iranian support

The Houthis began as an attempt to revive the culture and values of the Zaydi Shiite northern Yemeni minority sect in the late 1980s, but became increasingly political in the early 1990s, forming the Believing Youth, a mass movement under the group’s leader Hussein Al Houthi.

Al Houthi politicised the movement through the 1990s, turning it into an insurrectionist force, indoctrinating followers in summer camps and eventually paving the way for child soldier recruitment. His brother Abdul-Malik Al Houthi, the movement’s current leader, took on his role after Hussein was killed in a clash with government forces in 2004.

Early in the group’s formation, batches of adherents were sent to the Holy city of Qom, Iran, for religious instruction, part of an enduring partnership that has divided analysts as to its depth, materially and ideologically.

But it also includes a growing partnership with Lebanon’s powerful, Iran-backed armed group, Hezbollah.

A former Yemeni army general, who did not wish to speak on the record, told The National that Iran has become adept at resupplying the group by smuggling at sea, using civilian vessels, and moving supplies to remote inlets and ports.

“Houthis have been receiving parts for missiles and drones from Iran mainly through the sea corridors. If the US catches one shipment, it means there are maybe 10 others at the same time that weren’t caught and made their way into Houthi territories."

The former general stressed that “Iran isn’t the sole provider. They buy their parts from arms dealers all over the world. It's just a matter of money, and they have that. All they need is good contacts, and then everything else will be easy. And guess who has the longest contact list? Their ally, Hezbollah".

Analysts have compared the group’s Jihad Council to the body of the same name overseeing Lebanon’s Hezbollah, formed in the early 1980s with the assistance of Iranian advisers in the Islamic Revolutionary Guard Corps, a unit charged with assisting Iran’s foreign allies on military matters.

Hezbollah members parade during a gathering to commemorate Al Quds Day in a suburb of Beirut. Al Quds Day was declared in 1979 by the late Ayatollah Khomeini. EPA

By the 2011 Arab uprisings, Yemen’s army had been falling to pieces for years amid “coup proofing” – attempts by then dictator Ali Abdullah Saleh to ensure only loyalists had command positions – while rampant government corruption and human rights abuse undermined government support.

In 2011, the Houthis seized Saada, a key military point in the north with several military bases. “Saada is their bastion. Their main arm depots and factories are in those mountains. They are untouchable, every Yemeni knows that,” a government intelligence officer told The National.

As in Iraq when ISIS began their summer offensive that year, vast troves of military equipment fell under Houthi control, including anti-ship missiles, ballistic missiles and radars, an event helped by the group bringing anti-government supporters in the armed forces to their cause.

This image taken from video released by the media arm of Yemen's Houthi rebels claims to show the launch of the ballistic missile that landed in central Israel on September 15. Photo: Ansar Allah Media Office via AP

Key to this rise was the relinquishing of power by President Ali Abdullah Saleh in 2012 amid the turmoil of the uprisings. In 2014, he took many of his armed supporters to the Houthi cause, turning against the UN-recognised government.

With this brazen change in allegiance, Saleh took with him the Missile Brigades of the Yemeni army, supercharging the Houthi arsenal.

Saleh would be killed by the Houthis in 2017 amid growing tension with the movement, but not before about 60 per cent of Yemeni army weapons had been taken by the group.

“When President Saleh proposed a Saudi-Yemeni dialogue, the Houthis accused him of treason, surrounded his house and then killed him. The Houthis claimed he was trying to escape,” a source within Saleh’s General People's Congress (GPC) party told The National.

The looming blockade

Within two weeks of seizing Hodeidah in the west after taking over the capital, the Houthis detained 70 Egyptian fishermen. It may have been an early indicator of their intent for the waterway.

The group’s capabilities were growing, even if their intent was unknown. By 2014, the group was thought to have obtained about 100-300 ballistic missiles – powerful long-range rockets that plummet to their targets at several times the speed of sound – from government stockpiles.

Some, like the Soviet-era Tochka missile, are highly accurate, hitting a joint Yemeni-GCC base in September 2015, killing scores of soldiers. This was a rare incident because many of the group’s existing missiles were far less accurate Scuds, bought from Russia or North Korea in the 1980s.

The Tochka’s guidance, using the Russian GPS Glonass system, would be a harbinger of what was to come, as the group used publicly available technology for a host of targeting operations.

Until 2015, however, the group carried out only limited long-range attacks, nothing like the 2,000km strikes they have conducted against Israel recently, using Iran-supplied ballistic missiles.

That year, Iran went on record to say it had been training the Houthis, supporting evidence of an Iranian supply chain, part of which was intercepted by the US Navy on a smuggled shipment from Iran in 2013. In early 2015, senior IRGC commander Esmail Ghani, who now heads the powerful Quds Force, went on record to say "those defending Yemen have been trained under the flag of the Islamic Republic".

Attacks on ships began within months of this admission, ostensibly part of an effort by the group to pressure Saudi Arabia into a ceasefire. Those attacks were at first quite close to the narrow Bab Al Mandeb, involving boats and even rocket propelled grenades with ranges of only a few hundred metres.

Elsewhere, the group began rudimentary Scud missile attacks – the same inaccurate but highly explosive weapon Saddam Hussein used against Israel in 1991 – launching its first attack on Riyadh, one of hundreds.

In 2016, the Houthis claimed to have launched their first home-made missile, the Burkan, at Makkah, but analysts noted how the range of the missile was significantly longer than the group’s existing arsenal. Another attack that year targeted the American destroyer USS Mason with cruise missiles, prompting America's first strike on the group.

Meanwhile, suspicions of Iranian help were growing. By 2017, attacks were becoming yet more sophisticated at sea, the Houthis using exploding drone boats for the first time to strike vessels, weapons also said by experts to be based on Iranian designs.

Aware of this growing naval might, the Houthis soon warned a full blockade was possible. “Strategic choices will be taken as a no-return point, including blocking the international navigation in the Red Sea,” the group’s spokesman said in 2018.

James Brady, a researcher at the Centre for Science & Security Studies, says: “The cruise missiles and drones used by Houthis most likely rely on a mix of global navigation satellite systems. They're likely reliant on some or all of the global navigation satellite systems (GNSS) like GPS, Glonass, Galileo or Beidou systems. They provide global coverage to a very high degree of accuracy and the systems used by the Houthis likely rely on a mixture of signals for redundancy."

This staple of modern navigation would soon be used in fleets of Iran-designed and in some cases, Iran-manufactured drones, widely used against ships in the Red Sea.

Building the kill chain

These weapons alone are not good enough to find and hit a moving ship far out at sea, over the horizon. Even fast-moving missiles take minutes to reach targets hundreds of kilometres away, allowing ships to sail several kilometres, while for drones, that time can be far longer, meaning many weapons simply fly off towards a vague estimation of the target area.

What was needed was training, coming in the form of Unit 340, a branch of the IRGC specialising in ballistic missiles, in addition to trainers for the Houthis’ considerable force of drone operators. This would marry aerial reconnaissance using drones and boats, including the Iranian “spy ships” Behshad and Saviz, with the crude sensors on the missiles to build surprisingly accurate methods of hitting ships.

This network of cameras and guided weapons is known by military analysts as "a kill chain".

A screengrab taken from a Houthi video claims to show a 'Jaffa' drone used in the attack on Tel Aviv in July 2024. EPA

With the training in place, the group would soon need more arms, not only for the civil war but for the bombardment of neighbours.

By mid-2017, conflict monitoring organisation Acled estimated the group had entirely exhausted its stockpile of several hundred missiles, suggesting many, if not all, of the missiles fired at the Red Sea today are provided by Iran.

Subsequent drones, anti-ship and ballistic missiles used by the group and claimed by the Houthis to be indigenous designs, are said by most analysts, and several UN expert panels, to be near copies of Iranian weapons under different names.

“Although most Houthi missile and drone systems are believed to be manufactured locally, the Yemeni armed group lacks the industrial know-how and critical components (such as electronic parts, propellants and engines) to self-sufficiently develop sophisticated weapon systems,” says Leonardo Jaccopo Maria Mazzucco, an expert on Middle East security who has worked with the EU.

“Iran has systematically facilitated technology transfer, provided in-situ trainers and advisers, and smuggled critical pieces of equipment to the Houthis. On the other hand, the Houthi capture of pivotal state functions has provided the armed group with the means to extract revenues necessary to finance its war effort and expand its arsenal,” he says.

Many experts now worry the Houthis will have altered trade in the Red Sea for years, even if the Gaza war ends. Mr Mecogliano stresses how sensitive shipping companies are to risk and may factor in the longer trade route, around the Cape of Good Hope, as a permanent feature of operations. “Some may not return to the Red Sea,” he warns.

“If you go back into shipping history, when the Suez Canal closed because of the 1967 Six Day War, you had it closed for eight years, that's where you got the introduction of super tankers. That's where tankers went from small tankers to behemoths, because it was economical. And when the Suez Canal opened back up in '75, you still had the super tankers going around Africa.”

For the Houthi official, the attacks in the Red Sea "have created an environment that can offer the Yemeni armed forces [Houthis] a new opportunity to develop weapons, study air defences and enhance naval capabilities, both in terms of intelligence and technical/military aspects".

These are "new opportunities to test and develop more weapons", stressed the source.