Key Findings

• There are currently no indications that either the US or Iran’s “Axis of Resistance” have an appetite for wider conflict in the Middle East

• The 13-week old Houthi campaign against international shipping in the Red Sea and Gulf of Aden shows no signs of abating

• The Houthis are probably capable of conducting more damaging strikes than have been reported hitherto, but are acting with restraint for the moment

• If even a measured attack against a commercial or military vessel were to cause significant casualties, this could lead to an escalation

• The forthcoming holy month of Ramadan is not likely to precipitate an increase in Houthi attacks

Background - The Story So Far

Since 19th November 2023, at least 38 mainly commercial vessels transiting the Gulf of Aden and the Bab-al-Mandeb Strait have been targeted by the Yemeni Houthi group. Ostensibly undertaken in solidarity with HAMAS as the group continues to fight the Israel Defence Forces (IDF) in the Gaza Strip, 13 (34%) of the ships attacked have sustained some damage from either drone or anti-ship missile strikes. Additionally, two other commercial ships have been targeted to the southeast, in the Indian Ocean, in attacks that were almost certainly a part of the same campaign. Notwithstanding, no casualties have been reported and nearly all of the vessels have been able to proceed to port subsequently. There have also been six probable attempts to hijack vessels in the Red Sea, but gunmen have succeeded in boarding only two of the ships targeted. 

In response, since 11th January 2024, the US and UK have conducted at least three waves of joint airstrikes against targets in Yemen to degrade Houthi capability. Washington has also ordered its aircraft to conduct an unknown number of unilateral missions against similar sites. Exactly how much punishment Houthi targets have taken is impossible to assess, but their intent is undented as their attacks continue at a rate of between two and three per week.

Why Haven’t the Houthi Attacks Been More Effective?

The true military capability of the Houthis is something of a moot point. However, the recent attacks in the Red Sea and Gulf of Aden are indicative of a group well-supplied with drones and a variety of anti-ship missiles of mainly Iranian and former Soviet Bloc providence. The majority have likely been supplied directly by Iran or purloined during the Yemeni civil war. Media reporting also indicates that the Houthis have developed something of a homegrown industry for manufacturing their own weaponry - or at least copying that supplied by Tehran. As recently as 11th January this year, a team of US Navy SEALs attached to the 5th Fleet intercepted a dhow en route from Somalia to Yemen and found "Iranian-made ballistic missile and cruise missiles components". 

History shows that even military vessels can be put out of action by relatively cheap, unmanned drones. On the night of 31st January 2024, the Russian Tarantul-class missile boat, the Ivanovets, was sunk after being hit by five Ukrainian Magura V5 drones in the Black Sea. Each Magura costs around $273,000 as compared to $70 million for the Ivanovets, which was capable of carrying four anti-ship missiles. This is not a bad return on a small investment for a country with a navy consisting mainly of small patrol vessels. Moreover, in late 2023, the UK government estimated that Russia had lost up to 20% of its Black Sea fleet tonnage to such Ukrainian attacks.

Looking further back, in October 2000, two al-Qaeda suicide bombers crashed a small, fibreglass Zodiac speedboat packed with explosives into the side of the USS Cole, a $1 billion American Arleigh Burke guided-missile destroyer of the same class as the USS Carney, which is currently operating in the Red Sea. At the time, she was refuelling in Aden, Yemen, and 17 of her sailors were killed and 37 others injured. This attack took place long before remote-controlled drones and the success of such an operation now would not have to depend on suicide bombers willing to steer a device onto its target. Indeed, a worrying development came on 11th February, when US Central Command reported that one of its vessels had destroyed “two remotely controlled explosive-laden boats”. Also known as Unmanned Surface Vehicles (USV), they were somewhere near the Yemeni port of Hodeidah at the time. In another first  one week later, the US military also claimed to have destroyed a Houthi unmanned underwater vessel (UUV) somewhere near the coast of Yemen.

The most serious Houthi attack to date was the 18th February missile strike on the Rubymar, in the Bab al-Mandeb Strait. At the time of writing, unconfirmed reporting suggested that the crew may have had to abandon ship, although none were injured. Although given their bulk, large commercial vessels are quite difficult to sink, their size, low speed and lack of drone or missile countermeasures makes them relatively easy targets. Since the start of the Houthi campaign in the Red Sea, the international press has widely reported that US, UK and French military vessels have shot down missiles or drones on a number of occasions, almost certainly preventing more serious damage. However, with the Ukrainians proving that even military vessels can be sunk with drones, this does beg the question of why the Houthi attacks in the Red Sea  have not caused more damage or casualties.

First of all, the Ukrainians may simply be better equipped and have the advantage of intelligence support from their NATO allies, making their task easier than that of the Houthis. Additionally, there have been some signs that the recent US and UK airstrikes are impeding Houthi freedom of movement in the Red Sea. On 6th February, a British-owned ship named the Morning Tide was hit by a probable drone which, according to unconfirmed reporting, may have been launched from a nearby vessel rather than from on land. If this was the case, it might suggest that the air attacks are limiting Houthi freedom to launch projectiles from coastal areas. Indeed, three days before the Morning Tide attack, the US military reported that it had identified six anti-ship missiles ready for firing and destroyed them prior to launch. 

However, even if this is taken into account, the amount of reported damage from the Houthi attacks to date does seem low. As described earlier, 15 vessels have been hit by their extensive anti-ship arsenal, making it probable that the lack of damage or casualties is a question of intent rather than capability. If given totally free rein, the Houthis probably could cause more damage. One only has to look at their extremely professional hijacking of the Galaxy Leader on 19th November 2023. Although all the talk across the Middle East is currently that of “escalation” between Israeli, the US and their allies and Tehran’s “Axis of Resistance”, there does not appear to be any desire for widening conflict.

A further positive indication of this came on 18th February but passed almost unnoticed as the international media focused on the death of the Russian opposition leader, Alexi Navalny. It was reported that Brigadier General Esmail Qaani, the commander of the Iranian Revolutionary Guards Corps (IRGC) Quds Force, had met the leaders of several unnamed militant groups affiliated with Tehran at Baghdad International Airport (BIAP) in late January and instructed them to cease operations against US targets in Iraq. At the time of writing, his diktat seems to have been respected as there had been no such strikes reported since 4th February.

Tower 22

On 28th January, three American servicemen and women were killed when what was almost certainly a drone fired by Kataib Hezbollah - one of Iran’s Iraq proxy militias - struck an isolated base known as “Tower 22”, in northeastern Jordan. They were the first reported US casualties in the region since the HAMAS attack on 7th October. President Biden promised retaliation and this duly came on 2nd February 2024, when 85 targets across Syria and Iraq were hit by aircraft and missiles in a thirty minute window. 

Notwithstanding, the gap of nearly one week between the Tower 22 strike and the evening of 2nd February is a little curious. With the entire Dwight D. Eisenhower Carrier Strike Group at his disposal in the region - not to mention the US Fifth Fleet based not far to the north in Bahrain - Biden could probably have struck much earlier if he had chosen to. In addition, the President advertised his intention to attack several days before any aircraft took off, leading to the suspicion that he wanted to minimise casualties, giving Tehran more of a slap on the wrist than a major blow which could have increased the temperature across the region substantially. It is probably no coincidence that a spokesman for Harakat al-Nujaba, one of Iran’s Iraq proxies, subsequently claimed that the US targets in the country were “devoid of fighters and military personnel at the time of the attack”. 

This apparent tit-for-tat modus operandi can be compared to the ongoing situation on the Israel-Lebanon border. Since the 7th October HAMAS attack, the IDF and Hezbollah - Iran’s most powerful franchise in the Levant - have been engaged in daily, set-piece melees involving missile and rocket fire. The casualties reported - 146 on the Lebanese side of the frontier - have been comparatively low so far.

What Lies Ahead?

At this time, there are no signs that any of the main actors in the Middle East are looking for an escalation of violence. However, the Houthis could, almost certainly, conduct more effective attacks if they chose to, or were ordered to by Tehran. Even though they may bristle with sensors, the USS Cole attack showed that Western combat vessels are not infallible, even to small boats. Moreover, they only carry a finite number of weapons with which to counter the drone and missile threat from the Yemen coastline. Swarming much larger ships with multiple smaller vessels is an established Iranian modus operandi in the Persian Gulf and this could be quite easily transferred to drone operations, potentially overwhelming radars or onboard defence systems. Notwithstanding, there is no obvious intent to conduct any such operation at the moment.

Before the lethal drone attack against Tower 22 on 28th January this year, there had been some 160 strikes against US military assets in Syria and Iraq since the start of the HAMAS-Israel conflict in October 2023, none of them causing any major casualties or damage. Although it might be tempting to regard the three deaths at Tower 22 as an Iranian “escalation”, it is probable that this attack was no different in intent from any of the other previous 160; for whatever reason, the single drone just happened to get through US defences and strike home. Indeed, there has been some suggestion that it may have been mistaken by air defences for an inbound friendly aircraft, giving it unimpeded passage to its target.

A comparable threat does exist in the Red Sea and Gulf of Aden. The more missiles and drones launched by the Houthis, the greater the chance that one or two might just penetrate defences and cause much greater destruction and casualties to a commercial or even military vessel. The current situation in the Middle East is one of measured response by Washington and its allies on the one side and the “Axis of Resistance” on the other. However, there is a danger of unintended escalation attendant upon an attack such as that which occurred at Tower 22.

As a final word, Islam’s Holy Month of Ramadan is now fairly imminent, this year falling between 10th March and 9th April. Historically, the international media has tended to equate this period with an uptick in Islamic terrorist violence, but the evidence for this is largely anecdotal. During the Iraq insurgency following the US-led invasion of 2003, increases in mass casualty attacks during Ramadan and on other key dates in the Islamic calendar were a result of these attracting large numbers of people onto city streets to mark Iftar - the breaking of the Ramadan fast every evening - or to conduct pilgrimages. The strikes were not planned to specifically mark important dates. As things stand, there is no suggestion that Ramadan will have any significant impact on the Houthi campaign against international shipping.