Yemen Situation Update: November 2023

Escalating Houthi maritime attacks unlikely to lead to wider regional destabilization

As missile and drone launches toward Israel have failed to reach their intended targets, the Houthis have expanded their military activities into the Red Sea, seizing an Israeli-linked cargo vessel and launching missiles and drones at commercial ships and United States Navy warships. The group has threatened to continue the attacks as long as the military campaign in Gaza is ongoing.¹Ansarollah, ‘Naval Forces: We Continue To Carry Out Our Military Operations Against The Ships And Interests Of The Israeli Enemy,’ 22 November 2023 The risk to international shipping has drawn widespread international condemnation and warnings about potential retaliation.

Recent maritime attacks have garnered global attention, but they are not a new strategy for the Houthis. Since its expansion to the West Coast in 2015, the group has threatened international shipping lanes in the Red Sea, especially at the critical global chokepoint of the Bab al-Mandab Strait. Remarkably, the increased frequency, selective targeting, and weapon systems used over the past weeks point to a significant escalation of Houthi tactics. This show of increased capacity means that the group now poses a greater threat to international shipping.

This report investigates recent Houthi attacks in the Red Sea,²This report examines political violence and interception events involving the Houthis as attackers targeting vessels in the Red Sea. Sea mine incidents, which are generally not directly targeted, and attacks on ports and other land-based sites are excluded from the analysis. Houthi cross-border attacks at regional countries, including Israel, have also not been included. drawing comparisons with historical patterns of violence in the same region. It finds that, despite the heightened threat, the likelihood of a significant military or political response will likely remain low in the near future, due to international concerns about the risk of a wider regional destabilization and the impact on the Saudi-led peace process with the Houthis. 

Houthi attacks move closer to home 

Long-range attacks on Israel continue

As the Houthis continued their attacks against Israel, they expanded their list of targets to include Israel-linked vessels and the US warships protecting them. Following the group’s three missile and drone launches toward Israel in October, Houthi forces conducted another 10 attacks this month. However, the targets and locations of the attacks shifted from southern Israel to closer to home. The Houthis still carried out long-range missile and unmanned aerial vehicle (UAV) launches at Israel, but they also shot at US military assets off the Yemeni coast, as well as at two Israel-linked commercial vessels in the Red Sea.

The Houthis’ longer-range attacks toward southern Israel continue to prove ineffective. In November, the Israel Defense Forces (IDF) claimed to have shot down another four missiles and a UAV the Houthis launched toward Israel, marking seven confirmed interceptions since 7 October. However, none of the projectiles have reached Israel’s airspace. This lack of success, coupled with a broader escalation by the groups in the Iran-led ‘axis of resistance’³Farnaz Fassihi, Ronen Bergman, and Eric Schmitt, ‘Iran Looks to Houthi Proxies to Escalate Fight With Israel,’ New York Times, 8 December 2023 as they pressure Israel to end its military campaign in Gaza, led the Houthis to pivot to more attainable targets in the Red Sea.

Houthis re-open the maritime theater

Starting on 8 November with the shooting down of a US MQ-9 Reaper drone off the western coast, Houthi forces have launched numerous missiles and drones that have come into the proximity of US Navy vessels. Although the group has not claimed any of these attacks, and US officials have been cautious in their comments about whether their naval destroyers were the intended targets, there were three instances of American vessels shooting down Houthi-launched UAVs in their vicinity in November. A Houthi missile also crashed near the USS Mason.

The Houthis have previously denied responsibility for a series of attacks on the USS Mason and the USS Ponce in the Red Sea in 2016. Those attacks provoked the US to launch Tomahawk missiles that destroyed three radar stations on the western coast, in the only direct US military intervention against the group. However, this time, despite steadily escalating Houthi maritime activities and rising regional instability, the possibility of a direct US retaliation may be lower due to the different context, especially in terms of the conflict in Yemen.

The maritime operations also expanded to include commercial vessels with perceived links to Israel. In the most high-profile incident, and the first such operation by Houthi forces, helicopter-borne commandos rappelled onto the Bahamas-flagged, Japanese-operated car transport Galaxy Leader, seizing the vessel and its 25-member crew. The Houthis have hailed the operation as a huge success: although the vessel is not Israel-flagged, -operated, or -manned, the Houthis have been keen to emphasize that the Galaxy Leader is “Israeli-owned” — a likely reference to the fact that United Kingdom-based Ray Shipping, which owns the vessel, was founded by Israeli businessman Abraham ‘Rami’ Ungar.⁴The Guardian, ‘Yemen’s Houthi rebels seize cargo ship in Red Sea and call Israeli vessels “legitimate targets,”‘ 20 November 2023 The carrier has since been dragged to the coast of al-Hudayda, where it is being used as a tourist attraction and public relations stunt for Houthi leaders to gain popular sympathy.⁵Al-Arabiya, ‘Galaxy Leader ship seized by Yemen’s Houthis becomes a tourist attraction,’ 6 December 2023 

A subsequent attempted hijacking of the Central Park tanker in the Gulf of Aden was also initially widely blamed on the Houthis, as was at least one missile fired from Yemen toward the vessel shortly afterward, although the US later announced that the attackers were all Somali nationals.⁶US Department of Defense, ‘Pentagon Press Secretary Brig. Gen. Pat Ryder Holds an Off-Camera, On-the-Record Press Briefing,’ 27 November 2023 The group has denied any involvement in either incident, but the missile launch seems to have originated from Houthi-controlled territory, which, if confirmed, would be their first operation in the Gulf, reflecting an expansion in the group’s extra-territorial activities. Like the Galaxy Leader, the Central Park is part of a multinational corporation with Israeli founders — in this case, Zodiac Maritime, one of billionaire Idar Ofer’s businesses.⁷Jon Gambrell, ‘US Navy seizes attackers who held Israel-linked tanker. Missiles from rebel-controlled Yemen follow,’ Associated Press, 27 November 2023 Of note: Iran has previously targeted ships owned by both companies as part of its shadow war with Israel.⁸Jon Gambrell, ‘US Navy seizes attackers who held Israel-linked tanker. Missiles from rebel-controlled Yemen follow,’ Associated Press, 27 November 2023

Houthis join efforts to blockade Israel

The success of the Galaxy Leader raid stands in stark contrast to the group’s other maritime activities in November, which were all intercepted by US warships patrolling the Red Sea to protect international shipping. However, as with the ongoing drone and missile launches toward Israel, the failure to hit the target has not stopped Houthi figures and their allies from heralding the operations as successful. Many vessels are being forced to reroute from the Red Sea, pushing up insurance premiums, and creating longer shipping times, higher transport costs, and rising prices in Israel.⁹Assaf Gilead, ‘As ships reroute, cargo prices jump,’ Globes, 27 November 2023 This mirrors calls from Iranian leaders to impose an embargo on Israel by blocking oil and food imports and exports.¹⁰Reuters, ‘Iran’s Khamenei urges Muslim countries to boycott Israel,’ 1 November 2023 Although targeted at Israel, the impact will likely be felt across the region, including Yemen, in both Houthi- and Internationally Recognised Government (IRG)-controlled areas, especially if the attacks continue to escalate.¹¹Jonathan Saul, ‘Red Sea shipping costs rising after Houthis target more commercial vessels,’ Reuters, 12 December 2023 

The attacks also serve to boost the group’s profile domestically and regionally as it exploits strong sentiments about the Palestinian cause, even as pro-Palestine demonstrations have significantly fallen across Yemen after last month’s surge, from 548 to 301 events, representing a 45% drop. The majority — 263 of the 301 demonstration events — were Houthi-sponsored.¹²Houthi-sponsored events are classified as typically being organized and including local Houthi-aligned officials.

The evolution of Houthi maritime attacks

The Houthis carried out five maritime attacks in November, the most in a single month since the current conflict began. However, these are not the first Houthi operations in the Red Sea. The maritime theater has been an active part of the war in Yemen from the onset of the Saudi-led Coalition’s intervention in 2015. The group’s maritime strategy has evolved over time as its capabilities have developed (see graph below), territorial control has changed hands, and domestic and regional dynamics have shifted.

Changing tactics, targets, locations, and weapon systems

In the first two years of the conflict (2015-16), the group relied on close-range coastal access, operating only in areas where it held coastal control until it could develop longer-range capabilities. The first reported Houthi maritime attack was in October 2015, just over six months after the beginning of the current conflict, when Houthi forces lobbed artillery at a Coalition vessel off the coast of Dhubab in southwestern Taizz, near the Bab al-Mandab Strait. In the first 10 months of the conflict, the Houthis carried out nine attacks, all of which were shelling along the Taizz coastline of al-Mukha and Dhubab, targeting Coalition naval ships.

As seen in the chart above, the group’s tactics first began to evolve in February 2016 when Houthi forces fired their first anti-ship missile at a Coalition warship off the al-Khawkha coastline in southern al-Hudayda. The group’s other five attacks in 2016 also all involved missiles and were launched from the Taizz-southern al-Hudayda area, indicating the clustered nature of Houthi maritime attacks in the early years of the conflict. The targets for the attacks also began to shift to include United Arab Emirates naval vessels and US destroyers that were deployed to the region as a deterrence against the Houthi threat.

The attacks remained intermittent until 2017, when Houthi forces first deployed WBIEDs, otherwise known as remote-controlled bomb-laden boats, as the lower-cost devices allowed them to increase the rate of operations. Over the next two years, the group ramped up efforts to end the Coalition blockade on al-Hudayda port, increasing the frequency, range, and targets of maritime attacks to include ports and oil offloading sites on the Midi coast in Hajjah and in Jizan in southern Saudi Arabia and employing the novel tactic of naval commandos using fast-attack crafts to fire RPGs or tactical rockets at Saudi crude oil tankers. The escalation was a driver in the launch of a Coalition-sponsored IRG offensive on the western coast to retake the strategic port town of al-Hudayda.

While the offensive rapidly advanced from southern Taizz up the coast, the Houthis’ maritime operations dwindled as they lost ground and the environment was no longer conducive to launching attacks. This was followed by an eight-month halt from late 2018 after the signing of the Stockholm Agreement that brokered a truce in al-Hudayda and halted the IRG West Coast assault. The next year saw the fewest Houthi attacks, four, as well as a northern shift in attack launch sites.

In the two years following the Stockholm Agreement, the rate of attacks averaged just under one per month, and the bulk of incidents involved WBIEDs. All, but one, of the 22 Houthi attacks in the Red Sea in 2020 and 2021 were carried out using WBIEDs. The range of the attacks also increased, extending to target ships moored at oil facilities on the Saudi coast, over 1,000 kilometers from launch points in al-Hudayda.

Still, maritime activities dried up after the United Nations-meditated truce came into effect in April 2022 and remained paused during the subsequent unofficial truce, with one exception: The Houthis launched a missile that crashed into the sea in November, in the group’s last reported attack before this month.

New developments in the November attacks

The November maritime attacks have marked a notable shift in the Houthis’ tactics. The use of drones to target ships is a new development. The Houthis have previously used bomb-laden drones in cross-border attacks on Saudi Arabia and to strike government-controlled oil ports in southern Yemen to shut down oil exports, but never before in their Red Sea attacks. The drones have also been deployed in combination with other weapons, primarily anti-ship missiles, in another display of the Houthis’ more sophisticated military capabilities.

The success rate of the attacks in November has been slightly higher than in previous years. Between October 2015 and November 2022, out of 79 Houthi attacks targeting ships in the Red Sea, only 10 hit their intended target — a 13% success rate (see graph below). Of these, six targeted Saudi and Emirati naval ships, and the other four they struck were commercial vessels, three Saudi-flagged and one Turkish-flagged bulk carrier. 

Notably, four of the 10 incidents involved Houthi forces managing to get relatively close to the vessels aboard smaller craft, allowing them to either fire unguided rockets or board the ships. Prior to this month’s hijack of the Galaxy Leader, the Houthis were able to seize a Saudi tugboat off northern al-Hudayda and the Emirati Navy’s Rwabee landing craft near Ras Isa, presaging the latest operation. Displaying an advancement in training and materiel, the group landed a helicopter on the Bahamas-flagged carrier, rounding up the crew before they could retreat to the ship’s citadel.

The majority of the Houthis’ targeted attacks in the Red Sea have been directed at Coalition warships, IRG and Saudi ports, and affiliated commercial vessels. Following the start of the Israel-Gaza conflict, the range of Houthi targets grew to include Israel-linked vessels and US warships protecting them and will likely continue to expand as the Houthis try to redirect international shipping away from Israel. 

In a similar pattern of events, when the group expanded the attacks to include UAE vessels in 2016, the US Navy sent destroyers to the region to protect the Red Sea shipping lane. In response, the Houthis launched a series of missiles at the USS Mason and USS Ponce. Though all these missiles were either intercepted or crashed into the sea, the attacks provoked the US’ first military retaliation against the Houthis, with US cruise missiles striking three radar installations on the west coast. The latest incidents could follow a similar trajectory.

Why this time may be different

The Houthi track record of maritime operations goes back to 2015 and has grown more sophisticated over the next eight years. Before the 2022 UN-mediated truce, international concerns about the risk to international shipping lanes and the direct threat to Coalition naval and commercial vessels prompted a reciprocal military response. However, so far, the repeated Houthi attacks in the Red Sea have only provoked recriminations and warnings from both Israel and the US.

Israeli officials have largely distanced themselves from Houthi activities, avoiding reference to any Israeli ownership of the targeted vessels and instead describing them as international incidents for which Iran is to blame.¹³Ministry of Foreign Affairs, ‘Prime Minister’s Office Statement,’ 19 November 2023 Israel has also not retaliated against the drone and missile launches coming from Yemen, although it has reserved the right to respond if necessary.¹⁴Middle East Monitor, ‘Israel Air Force commander threatens to bomb Arab countries,’ 18 November 2023 This both reduces the need to react immediately and potentially get dragged into a wider regional conflagration, as well as allows for the option to target other Iranian-linked groups in any future tit-for-tat reciprocation.

The US has also eschewed militarily deterring the Houthis from further actions in the Red Sea. In addition to some uncertainty about whether the US Navy ships were the intended targets, and the Houthis have not claimed to have fired at any American vessels while stating that the US drone was over Yemeni waters, the warships are at limited risk due to their heavy defenses, although a lucky strike remains a possibility and could precipitate a reaction.

The Biden administration also seems to be considering wider regional dynamics, including the recent Iran-Saudi rapprochement. The US continues to support the ongoing Saudi-led peace talks between the Houthis and the IRG, which appeared to pick up renewed momentum earlier this month, and will likely try to avoid imperiling the process. In light of the talks, the US has been avoiding both military strikes and designating the Houthis a Foreign Terrorist Organization (FTO), which US lawmakers have been calling for and which Houthi officials have said would be “an act of war.”¹⁵Ansarollah, ‘President Al-Mashat: Any American Action That Harms Our Country Will Be Considered A Declaration Of War,’ 29 November 2023

Looking forward

• The shift to maritime operations and the subsequent steady expansion in the rate of attacks and range of targets over the past month suggests the Houthis will continue to escalate their attacks as long as the Israeli campaign in Gaza is ongoing. 
• In line with the rest of the ‘axis of resistance,’ the Houthis will try to ramp up the pressure on Israel and its perceived international backers by shifting from firing in the direction of and hijacking ships to directly targeting allegedly Israel-linked commercial vessels with anti-ship missiles and drones, although they are likely to use smaller, lighter projectiles at first. 
• Although Israel-linked ships are the Houthis’ stated targets, the group’s definition of ‘linked’ appears to be loose, and vessels with little to no connection to Israel could be impacted. The group may also extend its maritime operations from the Red Sea into the Gulf of Aden. The first half of December has already seen the Houthis broaden out their targeting to include all ships destined for Israeli ports.
• Some shipping companies have already begun to direct vessels away from the Bab al-Mandab, and more will likely follow suit as the risk of Houthi attacks rises, leading to longer transport times and higher costs. Traffic will also likely be routed away from the Houthi-controlled al-Hudayda to southern Yemeni ports, pushing up prices for imported goods.
• Direct military retaliation from either the US or Israel has been avoided so far, as neither seems to want to increase regional instability, but the countries may be more likely to respond if the Houthi attacks continue to escalate. Alternatives to military action, such as an FTO redesignation, are also not anticipated for the short term, particularly as Saudi-led peace talks continue.