Executive summary History of attacks on shipping Threats to commercial vessels in the Black Sea, the Taiwan Strait, and the South China Sea Houthi attacks on merchant vessels: A new form of aggression International response to the Houthis’ attacks The shipping industry’s response Improving strategies to counter attacks on shipping Preemptive diversion of shipping Intra-industry risk updates Use of directed-energy weapons Selective protection dependent on flag registration Freedom-of-navigation operations Disrupting the delivery of weapons Armed guards on board Conclusion Executive summary For as long as shipping has existed, merchant vessels have been vulnerable to attacks, especially in wartime. Starting in the beginning of the twentieth century, when international trade expanded rapidly, nations signed a string of treaties to protect merchant vessels from attacks by hostile states. With a few notable exceptions, most importantly the Iran-Iraq “Tanker War” in the 1980s, countries have complied with these rules.
Since the late 2010s, however, there has been a radical increase in state-linked attacks and harassment of merchant vessels. Around that time, Iran and, to a lesser extent, Israel began attacking vessels linked to the other side, primarily in the Strait of Hormuz, a situation that persists. China, for its part, has taken to harassing merchant vessels in the South China Sea in a strategy to enforce its unilateral territorial claims.
The harm imposed on merchant vessels further increased in November 2023, when the Iran-linked Houthi rebels launched geopolitically linked attacks on shipping in the Red Sea. Eight months later—despite interventions by the US Navy, the United Kingdom’s (UK) Royal Navy, European Union (EU) navies, and other Western navies—the attacks continue and have caused large-scale rerouting to the Cape of Good Hope. The increasing attacks on merchant vessels pose an acute threat not just to seafarers and shipping companies, but also to the global maritime order on which modern economies are based.
This report discusses the history of attacks on shipping, the rules implemented to keep shipping safe, and the new and serious threats posed by the Houthis and other actors. It also discusses steps Western governments and the shipping industry can take to reduce the harm posed by such attacks. These steps include: collective threats of rerouting away from risky waters; directed-energy weapons on naval vessels protecting merchant shipping; and increased focus on disrupting militias’ supply chains.
History of attacks on shipping “Japan’s dependence on international economic ties for its survival is well recognized...
In recent years, however, another source of vulnerability has assumed importance-the threat of international shipping disruptions in the Middle East.” Thus begins an article in the academic journal Pacific Affairs—not from 2023, but from 1986. In the Persian Gulf, Iraq had taken to attacking merchant ships linked to Iran as part of its war against the Islamic Republic.
The attacks began in 1981, the war’s second year, when Iraq attacked five merchant vessels, “largely to reduce Iran’s oil exports, which go entirely by sea and which help finance Iran’s war effort.” 1 Ronald O’Rourke, “The Tanker War,” Proceedings , US Naval Institute, May 1988, https://www.usni.
org/magazines/proceedings/1988/may/tanker-war . The following year, Iraq attacked sixteen vessels carrying Iranian oil; the next year, it was twenty-two. In 1984, Iran began responding in kind.
That year, Iraq attacked fifty-three tankers linked to Iran, while Iran attacked sixteen tankers linked to Iraq. By 1987, the numbers had risen to eighty-eight attacks by Iraq and ninety-one by Iran. The systematic attacks on the other side’s merchant vessels became known as the Tanker War, and it alarmed the outside world, which by that point was dependent on the supply of oil through the Persian Gulf.
“Mizuo Kuroda, Japanese ambassador to the United Nations, in the Security Council debate on the gulf conflict in May 1984, made an appeal that Iran and Iraq and all other states exercise the utmost restraint, and asked that both countries respect the right of safe navigation. (However, attacks on neutral shipping have continued.),” the Pacific Affairs article noted.
In the summer of 1987, after neutral Kuwait had concluded that Kuwaiti-flagged tankers could no longer travel through the Gulf and asked for permission to have them reflagged as American, the tankers were reflagged and the United States launched Operation Earnest Will, which saw US Navy vessels escort the US-flagged Kuwaiti vessels between the Gulf of Oman and their home ports. 2 Bradley Peniston, “Operation Earnest Will,” Navybook, last visited June 14, 2024, https://www.navybook.
com/no-higher-honor/timeline/operation-earnest-will/ . When the Iran-Iraq war ended the following year, more than 320 merchant mariners had been killed, injured, or were missing. Three hundred and forty merchant vessels had been damaged, some more than once.
Some 30 million tons of cargo had been damaged, while eleven ships had been sunk and three dozen declared total losses. 3 O’Rourke, “The Tanker War.” The Tanker War became infamous because it was a blatant case of aggression against merchant shipping as a tool of war, and it took place during a period in which countries’ economies were beginning to globalize.
The Warsaw Pact countries largely operated in parallel with Western market economies and China was still a mostly closed economy, but Japan and South Korea were trading heavily with Western economies,Latin American economies had also begun opening up, and Middle Eastern oil fueled many countries’ growing economies. It was against this background that the Tanker War was such a shock. It demonstrated to increasingly commercially linked countries that global shipping—the most important tool of global trade—could easily be targeted by interested nations and that there was little other countries could do to stop the attacks.
However, geopolitically motivated attacks on shipping are nearly as old as shipping itself. 4 Piracy is not covered in this report, which exclusively analyzes state-linked aggression against shipping Indeed, merchant vessels have been regularly attacked during wars. As H.
B. Robertson, Jr. notes During the Napoleonic era, both France and England utilized their differing strengths in an attempt to curtail the other’s logistic and commercial capabilities.
In the American Civil War, the blockade of the Confederacy was a principal component of the Union’s war strategy. The indispensable condition for victory by Japan in its 1905 war with Russia was control of the seas. Without this advantage, Russia could have resupplied its superior land armies from the sea.
During the progress of both WorId Wars, success of the maritime resupply effort of the Allied Powers, particularly Great Britain, was the sine qua non of victory. 5 H. B.
Robertson, Jr., “U.S.
Policy on Targeting Enemy Merchant Shipping: Bridging the Gap Between Conventional Law and State Practice,” in Richard J. Grunawalt, ed., International Law Studies 65 (1993), 338, https://digital-commons.
usnwc.edu/cgi/viewcontent.cgi?article=1744&context=ils#:~:text=The%20conundrum%20of%20this%20situation,legitimate%20targets%20of%20direct%20attack .
Until the nineteenth century, “privateers” also attacked merchant vessels on behalf of a country’s armed forces in exchange for bounties from the vessels. 6 “Privateer,” Britannica, last visited June 14, 2024, https://www.britannica.
com/technology/privateer . The reason merchant vessels have so systematically been attacked during wars is, of course, that they carry vital supplies to the adversary. “If it is true that merchant shipping can be critical to a nation’s ability to prosecute a war effort, it is equally true that the opposing power will seek to interdict that supply effort,” Robertson notes.
“Tactics, weapons systems and geography are variables that will affect any interdiction effort but the interdiction effort fits nearly with the general principles of war.” 7 Robertson, Jr., “U.
S. Policy on Targeting Enemy Merchant Shipping,” 338. Yet, by the time World War I erupted, nations realized that unrestricted warfare against merchant shipping was unsustainable and sought to restrict it.
Traditional (or customary) international law had established a distinction between enemy naval ships and enemy merchant vessels, with the latter granted protection from attacks. The Hague Conventions, to which forty-four countries agreed in 1907, included an article on the status of merchant ships following the outbreak of hostilities. It stipulated that “the belligerent may only detain it, without payment of compensation, but subject to the obligation of restoring it after the war, or requisition it on payment of compensation” and that “enemy merchant ships which left their last port of departure before the commencement of the war, and are encountered on the high seas while still ignorant of the outbreak of hostilities cannot be confiscated.
” 8 “Hague Convention VI—Status of Enemy Merchant Ships at the Outbreak of Hostilities: 18 October 1907, 205 Consol. T.S.
305, 3 Martens Nouveau Recueil (ser. 3) 533, entered into force Jan. 26, 1910,” University of Minnesota Human Rights Library, last visited June 14, 2024, http://hrlibrary.
umn.edu/instree/1907e.htm .
The Hague Convention became international customary law, the de facto legal baseline governing merchant shipping during armed conflict. This meant that “merchant ships, even those sailing under the flag of the enemy, are considered as civilian objects and manned by civilian crews, and so long as they maintain their proper role, are subject only to seizure as prize and subsequent condemnation in prize courts of the capturing belligerent. Only in special circumstances is the capturing power allowed to destroy the prize, and then only after removing the passengers, crew and ship’s papers to a place of safety.
” 9 Robertson, Jr., “U.S.
Policy on Targeting Enemy Merchant Shipping,” 339 Germany had, however, developed a submarine fleet. During World War I, these submarines set about attacking merchant vessels supplying the Allies. In the first months of 1917, following German submarine attacks on several US merchant ships, the United States declared war on Germany.
10 “American Entry into World War I, 1917,” US Department of State, last visited June 14, 2024, https://2001-2009.state.gov/r/pa/ho/time/wwi/82205.
htm . In the years after World War I, states sought to further codify merchant vessels’ rights, which resulted in the London Protocol of 1936. By 1939, all of World War I’s combatant countries except Romania had joined the protocol, which stipulated A warship, whether surface vessel or submarine, may not sink or render incapable of navigation a merchant vessel without having first placed passengers, crew and ship’s papers in a place of safety.
For this purpose the ship’s boats are not regarded as a place of safety unless the safety of the passengers and crew is assured, in the existing sea and weather conditions, by the proximity of land, or the presence of another vessel which is in a position to take them on board. 11 Ibid., 342.
Even so, World War II saw regular attacks on merchant vessels. International customary law was simply ignored. As a result, some vessels sought to reduce the risk of attack by sailing under neutral countries’ flags (including the increasingly popular flag of Panama).
As Robertson notes, both the Allies and the Axis powers attacked enemy merchant vessels—and sometimes even neutral merchant ships—and did so without ensuring the safety of the passengers, the crews, or the ships themselves, even though the protocol obliges warring parties to take such action. Both sides justified these practices either on the basis of reprisal (which in itself is an admission that absent the first violation by the other side, the practice is illegal under international law) or on assertions that the other side had incorporated its merchant fleet into the combatant force by mounting offensive weapons on the ships, convoying them, requiring them to report enemy submarine sightings, and ordering them to take offensive action against surfaced submarines. 12 Robertson, Jr.
, “U.S. Policy on Targeting Enemy Merchant Shipping,” 342.
Toward and after the end of World War II, the world’s nations attempted to create a global system of rules and institutions, with the United Nations (UN) at its center. In addition to the United Nations itself, nations created the International Civil Aviation Organization, the Food and Agriculture Organization, the World Health Organization (WHO), and a string of other bodies. In 1948, they adopted the Convention on the International Maritime Organization and agreed to form the Inter-Governmental Maritime Consultative Organization (IMCO).
The name was later changed to the International Maritime Organization (IMO) and came into force ten years after its adoption. The organization’s statutes placed little emphasis on maritime security, focusing instead on promoting economic action in support of freedom and reducing discrimination in some countries. 13 “Convention on the International Maritime Organization,” International Maritime Organization, 1948, https://www.
imo.org/en/About/Conventions/Pages/Convention-on-the-International-Maritime-Organization.aspx .
Article C, for example, states an IMCO aim “to provide for the consideration by the Organization of matters concerning unfair restrictive practices by shipping concerns.” 14 Ibid. Indeed, such was the desire for safe shipping among the world’s nations that a focus on security in the IMCO’s founding statute seemed unnecessary.
Harm caused by pirates and criminals posed a problem, but even the most ideologically opposed governments agreed that shipping needed to be kept safe. Countries deliberately harming merchant vessels was no longer acceptable. Even with the IMCO’s rules in place, ships continued to face considerable threats, but such threats came from criminals, terrorists, and malcontents.
In 1961, a group led by Captain Henrique Galvao hijacked the Portuguese passenger ship Santa Maria in protest against the regime of Antonio de Salazar. In subsequent years, Cuban exile groups attacked Russian and Cuban merchant vessels, though they sometimes got the wrong ship, and the Palestinian terrorist group PLFP attacked vessels bound for Israeli ports. Groups with other causes similarly found shipping a convenient target.
RAND researchers summarized the problem. Besides guerrillas and terrorists, attacks have been carried out by modern day pirates, ordinary criminals, fanatic environmentalists, mutinous crews, hostile workers, and foreign agents. The spectrum of actions is equally broad: ships hijacked, destroyed by mines and bombs, attacks with bazookas, sunk under mysterious circumstances; cargos removed; crews taken hostage; extortion plots against ocean liners and offshore platforms; raids on port facilities; attempts to board oil rigs; sabotage at shipyards and terminal facilities; even a plot to steal a nuclear submarine.
15 Brian Michael Jenkins, et al., “A Chronology of Terrorist Attacks and Other Criminal Actions against Maritime Targets,” RAND, September 1983, https://www.rand.
org/content/dam/rand/pubs/papers/2006/P6906.pdf . The Tanker War received such global attention because it was an extremely rare example of nation-states targeting merchant vessels.
The attacks created considerable risks for vessels beyond those linked to the two respective countries. “Like the Houthis today, the Iraqi and Iranian armed forces at that time weren’t always that accurate in their targeting,” noted Svein Ringbakken, a maritime executive with several decades in the business who now serves as managing director of the Norway-based maritime war insurer DNK. 16 Interview with the author, March 14, 2024.
Of the vessels attacked, sixty-one sailed under the Liberian flag, forty-one under the flag of Panama, thirty-nine under the flag of Cyprus, and twenty-six under the flag of Greece. A number of other Western countries similarly saw vessels sailing under their flag attacked. Forty-six were Iranian flagged.
Ringbakken added that “the ships that were going back and forth to [in the Gulf] were often attacked several times each, so the number of attacks were much higher than the 340 ships that were listed as having been attacked.” Had the merchant vessels carrying oil and other supplies through the Gulf been less sturdy, the human and material losses caused by the Tanker War would have been even more dramatic. But not even during the height of the Cold War, in the 1960s and 1970s, did NATO or Warsaw Pact member states systematically seek to harm merchant vessels linked to the other side.
NATO and Warsaw Pact countries indisputably acted unethically in other ways, but in the maritime domain they respected rules, conventions, and the neutrality of merchant shipping. They did so not least because they also depended on ships carrying goods to and from their countries being able to travel safely. Indeed, when the attacks by terrorists and other non-state entities continued, the world’s nations convened to negotiate and adopt the International Convention for the Safety of Life at Sea (SOLAS), the fifth version of global shipping’s cornerstone safety treaty, which governs the safety of the vessels themselves.
(Previous versions had been adopted in 1914—in response to the Titanic disaster—and then in 1929, 1948, and 1960.) 17 “International Convention for the Safety of Life at Sea (SOLAS), 1974,” International Maritime Organization, 1974, https://www.imo.
org/en/About/Conventions/Pages/International-Convention-for-the-Safety-of-Life-at-Sea-(SOLAS),-1974.aspx . Five years later, in 1979, nations adopted the International Convention on Maritime Search and Rescue (SAR), which entered into force in 1985.
SAR governs the responsibilities of coastal states in maritime search and rescue; the 1979 version divided the world’s oceans into thirteen search-and-rescue regions and introduced the obligation for countries to operate rescue co-ordination centers on a twenty-four-hour basis with trained, English-speaking, staff. 18 Ibid. International maritime rules, treaties, and conventions will be discussed at greater length in a later report.
The crowning achievement of Cold War maritime agreements took place in 1982, when negotiators representing 160 nations adopted the United Nations Convention on the Law of the Sea (UNCLOS), the “constitution of the oceans.” 19 Tullio Treves, “United Nations Convention on the Law of the Sea,” Audiovisual Library of International Law, December 10, 1982, https://legal.un.
org/avl/ha/uncls/uncls.html . UNCLOS entered into force in 1994.
UNCLOS covers crucial areas including exploitation of ocean and seabed resources, as well as maritime transit rights. Crucially, coastal states are given territorial rights over waters extending twelve nautical miles from their coastlines; foreign vessels have the right to sail through these waters under UNCLOS’s “innocent passage” provision. Coastal states are also given limited rights in the Exclusive Economic Zones extending another two hundred nautical miles beyond their territorial waters.
20 “United Nations Division for Ocean Affairs and the Law of the Sea, United Nations Convention on the Law of the Sea of 10 December 1982: Overview and Full Text,” United Nations, 1982, https://www.un.org/depts/los/convention_agreements/convention_overview_convention.
htm . A rare case of apparently state-linked attacks on merchant shipping took place in 1984, when nearly twenty vessels transiting the Red Sea were struck by mines. Egyptian and Western authorities subsequently identified the Ghat, a Libyan-flagged merchant vessel, as the culprit.
Libya’s motivation for the attacks appears to have been ruler Muammar al-Qaddafi’s desire to demonstrate what he punish other Arab regimes’ misguided policy of maintaining close relations with the West. 21 Richard A. Mobley, “Revisiting the 1984 Naval Mining of the Red Sea: Intelligence Challenges and Lessons,” Studies in Intelligence 66, 2 (June 2022), 22f, https://www.
cia.gov/resources/csi/static/RedSeaMiningMystery1984.pdf .
From the early 1990s, the end of the Cold War and the beginning of more harmonious relations between crucial groupings of countries decreased geopolitically linked risk everywhere, including in shipping. Crucially, the end of the Cold War delivered an extraordinary rise in commercial relations between previously hostile countries. In addition, China had begun opening up its closed economy in the 1980s and was quickly becoming a manufacturing hub for Western companies.
The rapidly growing trade and resulting globalization were facilitated by global shipping. Between 1990 and 2019, global shipping grew nearly threefold, from 4,008 million tons loaded to 11,076 million tons loaded. 22 Felix Richter, “The Steep Rise in Global Seaborne Trade,” Statista, March 26, 2021, https://www.
statista.com/chart/24527/total-volume-of-global-sea-trade/ . During the 1990s and 2000s, and until the late 2010s, shipping had to contend with spikes in piracy attacks, but geopolitically linked attacks remained minimal.
The few attacks that took place, most prominently an explosion on the French-flagged oil tanker Limburg off the coast of Yemen, were carried out by terrorists. 23 “U.S.
Charges Saudi for 2002 Oil Tanker Bombing,” Maritime Executive, February 6, 2014, https://maritime-executive.com/article/US-Charges-Saudi-for-2002-Oil-Tanker-Bombing-2014-02-06 . In Nigeria in the early 2000s, the Movement for the Development of the Niger Delta—a local militant group—kidnapped oil workers and attacked oil facilities and pipelines, though this was done in protest against inequalities in Nigeria.
The mostly peaceful period ended around 2019, when a proxy war targeting merchant vessels unfolded in the Strait of Hormuz, an indispensable body of water through which more than 20 percent of global petroleum travels. 24 “The Strait of Hormuz is the World’s Most Important Oil Transit Chokepoint,” US Energy Information Administration, November 21, 2023, https://www.eia.
gov/todayinenergy/detail.php?id=61002 . In 2018, Donald Trump’s administration took the United States out of the Joint Comprehensive Plan of Action (JCPOA), also known as the “Iran nuclear deal.
” Soon after that, Iran began to regularly harass merchant vessels in the Strait of Hormuz. In a particularly high-profile incident, Iran’s Islamic Revolutionary Guard Corps (IRGC) seized the Swedish-owned, UK-flagged oil tanker Stena Impero passing through the Strait of Hormuz on July 19, 2019, and took the crew hostage. 25 “Stena Impero: Seized British Tanker Leaves Iran’s Waters,” BBC, September 27, 2019, https://www.
bbc.com/news/world-middle-east-49849718 . Though the IRGC alleged that the tanker had struck a fishing boat and failed to obey IRGC instructions, there was no evidence of this.
Since then, attacks on merchant vessels have continued. Merchant vessels sailing under flags ranging from those of Norway to the United Arab Emirates have been struck by mines, magnetic mines, and torpedoes. 26 Patrick Wintour, “A Visual Guide to the Gulf Tanker Attacks,” Guardian, June 14, 2019, https://www.
theguardian.com/world/2019/jun/13/a-visual-guide-to-the-gulf-tanker-attacks . In August 2023, the United States dispatched a naval and Marine force to the strait to “support deterrence efforts.
” 27 C. Todd Lopez, “U.S.
Forces Arrive to Support Deterrence Efforts at Strait of Hormuz,” US Department of Defense, August 7, 2023, https://www.defense.gov/News/News-Stories/Article/Article/3485733/us-forces-arrive-to-support-deterrence-efforts-at-strait-of-hormuz .
By that point, there had been twenty attacks on merchant shipping in the strait since the beginning of 2021, including two on July 5, 2023, when Iranian naval vessels attempted to seize two oil tankers. 28 Heather Mongilio, “Video: Iranian Navy Warship Fires on Oil Tanker in the Strait of Hormuz,” USNI News, July 5, 2023, https://news.usni.
org/2023/07/05/video-iranian-warship-fires-on-oil-tanker-in-the-strait-of-hormuz . The US Navy and Marine presence appears to have succeeded in deterring the aggression, which subsided after the force’s arrival. As with all deterrence measures, though, it’s impossible to know whether the attackers had already been planning to reduce their aggression or whether the deterrence measures changed their cost-benefit calculus.
Threats to commercial vessels in the Black Sea, the Taiwan Strait, and the South China Sea In early 2022, another threat to global shipping emerged when Russia deployed close to two hundred thousand troops to its border with Ukraine. It was clear that any invasion by Russia would also involve attacks on Ukraine’s Black Sea ports and on shipping in the Black Sea. In the weeks immediately following the invasion, several merchant vessels in Ukrainian waters and ports were struck in suspected Russian attacks.
On February 25, for example, a tanker was struck by missiles. Two crew members were injured, and the crew was forced to abandon ship. 29 “Merchant Ships Attacked and on Fire off Ukraine,” Maritime Executive, March 25, 2022, https://www.
maritime-executive.com/article/merchant-ships-attacked-and-on-fire-off-ukraine . On March 2, a Bangladeshi seafarer was killed when a shell hit his vessel in the Ukrainian port of Olvia.
30 Matt Coyne and Gary Dixon, “Engineer Killed in Attack on Bangladeshi Bulker in Black Sea,” TradeWinds, March 2, 2022, https://www.tradewindsnews.com/casualties/engineer-killed-in-attack-on-bangladeshi-bulker-in-black-sea/2-1-1177847 .
In addition, when Russia invaded, ships crewed by some 800–1,000 seafarers were docked in seven Ukrainian ports and, in practice, unable to leave. Being stuck in Ukrainian ports, of course, made them an easy target for Russian attacks and also raised the risk of their becoming collateral damage of attacks against other targets. 31 Elisabeth Braw, “Foreign Seafarers Are Stranded in Ukraine for Christmas,” Foreign Policy, December 27, 2022, https://foreignpolicy.
com/2022/12/27/seafarers-stranded-ukraine-christmas-russia-war/ . “There were more than 90 vessels [stuck in Ukrainian ports] to start with, and during the [UN-negotiated grain] Corridor [between Russia and Ukraine that allowed ships carrying grain to leave Ukrainian ports, traveling through a Black Sea corridor on to international destinations], about 30 got out. We ended up with around 65 claims for total loss,” said Neil Roberts, the secretary of the maritime insurance industry’s Joint War Committee, which lists international waters according to risk level.
32 Interview with the author, April 5, 2024. Shipping in the Taiwan Strait has been similarly threatened, but has not yet been attacked. When, in April 2023, President Tsai Ing-wen of Taiwan met with US Speaker of the House Kevin McCarthy in California, Beijing registered its displeasure by launching an offensive military exercise targeting Taiwan and sending a coast guard “inspection flotilla” to the Taiwan Strait.
The strait is the main passage for cargo moving between Southeast Asia and Japan, South Korea, and northern China, which makes it one of the world’s busiest maritime thoroughfares; some 240–500 ships per day, including nearly nine in ten of the world’s largest container vessels, pass through the strait on an average day. 33 Alexander Lott, Hybrid Threats and the Law of the Sea (Leiden, Netherlands: Brill, 2021),172, https://brill.com/display/book/9789004509368/BP000013.
xml?language=en&body=pdf-60830 ; Katie Zeng Xiaojun, “East Asia: Impact of China and Taiwan Conflict on Shipping,” Maritime Intelligence, September 6, 2022, https://www.riskintelligence.eu/analyst-briefings/east-asia-impact-of-china-and-taiwan-conflict ; “Taiwan Strait: Pray We’ll Always Be as Lucky,” Lloyd’s List, August 5, 2022, https://www.
lloydslist.com/LL1141850/Taiwan-Strait-pray-well-always-be-as-lucky . Beijing, which considers Taiwan a region of China, argues it has “sovereignty and jurisdiction” over the strait, while Taiwan and countries including the United States consider it international waters divided along the strait’s unofficial median line.
By threatening to inspect ships passing through the strait, on the basis of legal powers not recognized by Taiwan and large parts of the international community, China would be able to severely disrupt shipping in the strait and, thus, cause considerable problems for shipping globally. Yet, the deployment of an inspection flotilla—whether or not it carries out any inspections—hardly reaches the threshold where the US Navy or another navy would consider it necessary to intervene. In its law-enforcement scope of inspections of merchant vessels (albeit on Taiwan’s side of the median line), China’s inspection flotilla differs from the overtly aggressive actions China’s coast guard, maritime militia, long-distance fishing fleet, and other maritime entities take.
All, though, constitute a risk to civilian vessels. Roberts noted China has long been “leaning in” via its fishing fleet, and it’s been building all these little islands in the South China Sea. The Chinese government issues white papers to float their ideas, for example saying they’ll allow their Coast Guard to fire on all vessels in their territorial waters.
And if nobody reacts, then they make it policy. Whilst the littoral states do not agree, they’re up against a huge nation and there’s no one in the area who’s in a position to react. That comparative disparity is what China has leveraged in deploying the inspection flotilla to the Taiwan Strait.
34 Interview with the author, April 5, 2024. China’s construction of artificial islands and its long-distance fishing fleet, whose estimated nearly seventeen thousand vessels fish other countries’ waters dry, will be examined in a subsequent report within the Atlantic Council’s Threats to the Global Maritime Order project. In addition, China’s maritime militia, coast guard, and long-distance fishing fleet habitually harass vessels, including civilian ones.
These activities are of particular concern in the South China Sea, through which approximately one-third of global trade travels, as China claims some 90 percent of these waters under its “nine-dash line” policy. 35 Bec Strating, “China’s Nine-Dash Line Proves Stranger than Fiction,” Interpreter, April 12, 2022, https://www.lowyinstitute.
org/the-interpreter/china-s-nine-dash-line-proves-stranger-fiction ; Anthony H. Cordesman, Arleigh A. Burke, and Max Molot, “The Critical Role of Chinese Trade in the South China Sea,” in China and the U.
S.: Cooperation, Competition and/or Conflict an Experimental Assessment, Center for Strategic and International Studies, October 1, 2019, http://www.jstor.
org/stable/resrep22586.30 . These practices, which will be analyzed in a subsequent report as part of the Atlantic Council’s Maritime Threats project, are not specifically targeted against shipping but instead target a wide range of vessels, including civilian ones.
Survey vessels sailing under the flags of Norway and Vietnam, for example, have been harassed by a combination of Chinese vessels. 36 Gregory B. Poling, Tabitha Grace Mallory, and Harrison Prétat, “Pulling Back the Curtain on China’s Maritime Militia,” Center for Strategic and International Studies and Center for Advanced Defense Studies, November 2021, 5, https://csis-website-prod.
s3.amazonaws.com/s3fs-public/publication/211118_Poling_Maritime_Militia.
pdf?VersionId=Y5iaJ4NT8eITSlAKTr.TWxtDHuLIq7wR . Since the beginning of the 2020s, the harassment has increased significantly, creating an environment of heightened uncertainty and risk for merchant vessels.
This uncertainty is heightened because it’s entirely unclear how coastal states and de facto protectors of the global maritime order, most notably the US Navy, can deter such activities. As Ringbakken noted China has its Navy, it has its Coast Guard and it has the militia and the fishing boats and this kind of crossover between the fishing boats and the militia, which is a strange construct. And China has a long-term perspective.
These small skirmishes and the small transgressions are not viewed as an attempt to undercut the global maritime regime, but that’s what they are. It’s what you might call the Chinese water torture method. Any kind of countermeasure from the Americans or others would seem disproportionate.
The activity is just merely little bit out of normal and not like what the Houthis are doing in the Red Sea, and that makes responding even harder. You don’t send a naval group to try to stop this kind of behavior because it seems too minor. So it goes on.
37 Interview with the author, March 14, 2024. The US military has come to much the same conclusion. “It’s getting more aggressive, they’re getting more bold and it’s getting more dangerous,” Admiral John Aquilino told media in late April 2024, shortly before handing over command of the US Indo-Pacific Command.
He added that China was increasing its aggression through a “boiling the frog” strategy. “There needs to be a continual description of China’s bad behavior that is outside legal international norms,” he noted. “And that story has to be told by all the nations in the region.
” 38 Demetri Sevastopulo, “US Pacific Commander Says China Is Pursuing ‘Boiling Frog’ Strategy,” Financial Times, April 28, 2024, https://www.ft.com/content/f926f540-d5c2-43f2-bd8f-c83c0d52bcda .
Indeed, China’s maritime harassment can easily be expanded to target many more cargo ships, in addition to the fishing vessels and supply vessels that have until now been the most frequently targeted categories. In the area of unilateral inspection flotillas , if the flotilla that was dispatched during Tsai’s visit to California were to be followed by similar measures, shipping companies and their insurers would need to assess whether it’s worth sending vessels through the Taiwan Strait. “Even if the US Navy wanted to intervene, it would be seen a gross intrusion, and it could spark something far worse.
The merchant ships are on their own,” Roberts noted. 39 Interview with the author, April 5, 2024. Ships don’t need to go through the strait to reach destinations other than Taiwan; they can simply travel along Taiwan’s eastern coast.
That route, however, would render them unable to call at Taiwan’s main port—the massive Port of Kaohsiung—or the Port of Taipei. This is what makes a blockade of Taiwan, whether executed by the China Coast Guard, the People’s Liberation Army Navy, China’s maritime militia, or a combination of the three, possibly with other entities also involved, such a troubling scenario. 40 Marek Jestrab, “A Maritime Blockade of Taiwan by the People’s Republic of China: A Strategy to Defeat Fear and Coercion,” Atlantic Council, December 12, 2023, https://www.
atlanticcouncil.org/content-series/atlantic-council-strategy-paper-series/a-maritime-blockade-of-taiwan-by-the-peoples-republic-of-china-a-strategy-to-defeat-fear-and-coercion/ . “What would happen to Taiwan if ships don’t call at its ports? Well, ultimately the people of Taiwan will starve ,” Roberts said.
“But shipowners have to focus on crew welfare and they’d just go around [east of Taiwan] and take a bit more fuel. It’s really difficult.” 41 Interview with the author, April 5, 2024.
Houthi attacks on merchant vessels: A new form of aggression On November 19, 2023, armed commandos belonging to the Yemeni Houthi militia stormed the Galaxy Leader, a Bahamas-flagged roll-on, roll-off (RORO) carrier traveling through the Red Sea near the Yemeni port of Hodeida. The commandos, who filmed themselves arriving in a helicopter, took the twenty-five-strong crew hostage and directed the Galaxy Leader to Hodeida and then the port of Al Saleef, which is also controlled by the Houthis. 42 “Hijacked Car Carrier’s Crew Treated ‘As Well As Can Be Expected,’” Maritime Executive, December 5, 2024, https://maritime-executive.
com/article/hijacked-car-carrier-s-crew-treated-as-well-as-can-be-expected . The Galaxy Leader had apparently been targeted because it is part-owned by Israeli national Abraham “Rami” Ungar, though his firm is registered in the United Kingdom. “The Yemeni Naval Forces managed to capture an Israeli ship in the depths of the Red Sea taking it to the Yemeni coast.
The Yemeni armed forces deal with the ship’s crew in accordance with the principle and values of our Islamic religion,” Houthi spokesman Yahya Sare’e declared on X on the same day. The Yemeni armed forces reiterate their warning to all ships belonging to or dealing with the Israeli enemy that they will become a legitimate target for armed forces. [.
..] Yemeni armed forces confirm that they will continue to carry out military operations against the Israeli enemy until the aggression against Gaza stops and the heinous acts against our Palestinian brothers in Gaza and the West Bank stop.
..If the international community is concerned about regional security and stability, rather than expanding the conflict, it should put an end to Israel’s aggression against Gaza.
43 Yahya Sare’e (@Yahya_Saree), “The Yemeni Naval Forces managed to capture an Israeli ship in the depths of the Red Sea taking it to the Yemeni coast. The Yemeni armed forces deal with the ship’s crew in accordance with the principle and values of our Islamic religion,” Twitter, November 19, 2023, 11:23 a.m.
, https://twitter.com/Yahya_Saree/status/1726290072994296194 . “All ships belonging to the Israeli enemy or that deal with it will become legitimate targets,” the Houthis added in a statement after the hijack.
44 Isabel Debre and Jon Gambrell, “Yemen’s Houthi Rebels Hijack an Israeli-Linked Ship in the Red Sea and Take 25 Crew Members Hostage,” Associated Press, November 20, 2023, https://apnews.com/article/israel-houthi-rebels-hijacked-ship-red-sea-dc9b6448690bcf5c70a0baf7c7c34b09 . The opportunistic labeling of the attacks as being an act of support for the people of Gaza was a clever move by the Houthis, gaining the attacks attention far beyond the global maritime community and gaining the Houthis sympathy for their actions among the public in countries troubled by Gazans’ plight.
It also made any response by the United States and other Western countries geopolitically fraught. A few days later, assailants identified as Houthis attacked the Israel-linked tanker Central Park in the Gulf of Aden, the body of water that leads into the Red Sea. 45 Ibid.
On December 3, the Houthis attacked three additional vessels. 46 U.S.
Central Command (@CENTCOM), “Today, there were four attacks against three separate commercial vessels operating in international waters in the southern Red Sea. These three vessels are..
.” X post, December 3, 2023, https://x.com/CENTCOM/status/1731424734829773090 .
The attacks continued, though the targeted vessels’ alleged Israeli links were not always clear or even existent. On December 9, the militia expanded its scope, saying it would also target ships headed for Israeli ports. Two days later, it hit the Strinda, a tanker owned, managed, and flagged in Norway and crewed by Indians, which the Houthis said was headed for Israel, though the owner said the tanker was bound for Italy.
47 Nadine Awadalla, Terje Solsvik and Phil Stewart, “Yemen’s Houthis Claim Missile Attack on Norwegian Tanker in Tense Middle East,” Reuters, December 12, 2023, https://www.reuters.com/world/middle-east/cruise-missile-yemen-strikes-tanker-ship-us-officials-2023-12-12/ .
On December 15, a Houthi drone struck the Liberian-flagged Al Jasrah and two Houthi missiles struck the MSC Palatium III, which was also sailing under Liberian flag; both were thought to be headed for Israeli ports. On the same day, the Houthis threatened another Liberian-flagged vessel, the MSC Alanya, and told it to turn around. 48 John Gambrell, “2 Attacks Launched by Yemen’s Houthi Rebels Strike Container Ships in Vital Red Sea Corridor,” Associated Press, December 15, 2023, https://apnews.
com/article/yemen-houthi-ship-attack-israel-hamas-69289146266b9042b5896aa4679605ef . “The Houthis’ targeting mechanism wasn’t that good, or their intelligence wasn’t entirely up to speed,” Ringbakken said. “And we don’t know for sure whether that was by chance or whether they didn’t mind a little bit of collateral damage because that got them more attention.
” 49 Interview with the author, March 14, 2024. Indeed, the Houthis appear to have decided to make necessity into an extraordinary virtue. Instead of having to conduct painstaking research into vessels’ complex ownership and management structure, and their cargo’s provenance and destination, the Houthis—while declaring that they were targeting Israeli-linked vessels—attacked a range of merchant vessels in the Red Sea, the Bab el-Mandeb Strait, and the Gulf of Aden.
That, of course, has made the waters unsafe for vessels form all countries, though the Houthis appear to consistently have exempted vessels linked to Russia and China. Retired Rear Admiral Nils Wang, a former chief of the Danish Navy, noted the following. It’s instructive to compare the Houthis’ attacks to the piracy of the Horn of Africa [that was particularly frequent in the early 2010s].
With the pirates off the Horn of Africa, the intimidation of international shipping was the same. That made launching a counter-piracy operation straightforward. Everybody, including China, Pakistan, Iran, everybody was of the opinion that this piracy had to be stopped.
Indeed, the military operations against piracy at that time were probably the biggest multinational military operation that has ever taken place, if you count on how many countries, regions, and continents were involved. Everyone agreed that the piracy had to be stopped. If you then compare that to the situation now in the Red Sea, the Houthis only seem to be targeting ships linked to the West, not to Russia and China.
And it’s only the Western world that is intervening to protect the ships there. 50 Interview with the author, March 28, 2024. By pure coincidence, the IMO Assembly—the IMO’s governing body—was scheduled to hold its biannual meeting in late November and December 2023.
Various items had been submitted for consideration by the assembly, including measures to prevent the growing dark fleet. 51 The dark fleet will be the subject of a subsequent report. Unsurprisingly, the Houthis’ attacks received urgent attention.
The Bahamas, the world’s eighth-largest flag state, criticized the Houthis’ attacks on merchant vessel as a “violation of all of the norms relating to innocent passage of ships.” 52 “Crew of Seized Galaxy Leader Allowed ‘Modest’ Contact with Families—Shipowner,” Reuters, December 5, 2023, https://www.reuters.
com/world/middle-east/crew-seized-galaxy-leader-allowed-modest-contact-with-families-shipowner-2023-12-05/ . And, referring to the Houthis, the country added, “Here we have non-state actors so who do you hold responsible?” That is the dilemma posed by the Houthis’ novel campaign against shipping. The militia attacks ships ostensibly for geopolitical reasons, and it’s backed by a nation-state, but it’s not an official government.
The militia is also linked to Iran but doesn’t officially represent this country either. “That makes it difficult to make this a matter between a hostile country and other countries, but at the same time, the Houthis are a completely different category from pirates and other opportunistic attackers without government links,” Wang said. 53 Interview with the author, March 28, 2024.
It should, therefore, come as no surprise that Western governments have struggled to formulate strategies to deter the attacks. International response to the Houthis’ attacks On December 18, the United States announced the establishment of Operation Prosperity Guardian, a naval task force comprising the United States, the United Kingdom, Bahrain, Canada, Denmark, France, Italy, Netherlands, Norway, the Seychelles, Spain, and several other nations, amounting to a total of twenty countries. 54 Phil Stewart, “More than 20 Countries Now Part of US-led Red Sea Coalition, Pentagon Says,” Reuters, December 22, 2023, https://www.
reuters.com/world/more-than-20-countries-now-part-us-led-red-sea-coalition-pentagon-2023-12-21/ . Some opted not to divulge their participation out of concern that doing so could increase the risks for their countries.
“The recent escalation in reckless Houthi attacks originating from Yemen threatens the free flow of commerce, endangers innocent mariners, and violates international law,” US Secretary of Defense Lloyd Austin said in the press release announcing the task force. “The Red Sea is a critical waterway that has been essential to freedom of navigation and a major commercial corridor that facilitates international trade. Countries that seek to uphold the foundational principle of freedom of navigation must come together to tackle the challenge posed by this non-state actor launching ballistic missiles and uncrewed aerial vehicles (UAVs) at merchant vessels from many nations lawfully transiting international waters.
” 55 “Statement from Secretary of Defense Lloyd J. Austin III on Ensuring Freedom of Navigation in the Red Sea,” US Department of Defense, press release, December 18, 2023, https://www.defense.
gov/News/Releases/Release/Article/3621110/statement-from-secretary-of-defense-lloyd-j-austin-iii-on-ensuring-freedom-of-n/ . Operation Prosperity Guardian is set up as “highway patrol in the Red Sea and the Gulf of Aden” with the task of averting attacks on merchant vessels, not punishing the Houthis. 56 Jim Garamone, “Ryder Gives More Detail on How Operation Prosperity Guardian Will Work,” US Department of Defense, December 21, 2023, https://www.
defense.gov/News/News-Stories/Article/Article/3624836/ryder-gives-more-detail-on-how-operation-prosperity-guardian-will-work/ . It will “respond to and assist as necessary commercial vessels that are transiting this vital international waterway,” Pentagon spokesman Major General Pat Ryder said in a briefing on December 21.
57 Ibid. “It’s a defensive coalition meant to reassure global shipping and mariners that the international community is there to help with safe passage.” 58 Ibid.
Prosperity Guardian is a fitting name for a naval coalition tasked with thwarting the attacks on merchant vessels in the Red Sea and the adjacent Bab el-Mandeb Strait and Gulf of Aden. The water forms a crucial thoroughfare in the globalized economy; under normal circumstances, some 15 percent of global maritime trade passes through it. 59 Parisa Kamali, et al.
, “Red Sea Attacks Disrupt Global Trade,” International Monetary Fund, March 7, 2024, https://www.imf.org/en/Blogs/Articles/2024/03/07/Red-Sea-Attacks-Disrupt-Global-Trade .
Indeed, in deciding to attack shipping, the Houthis have opted for the form of aggression that would yield by far the most global disruption and attention. Since December 19, Prosperity Guardian’s members have escorted merchant vessels with links to a wide range of countries (not just the countries involved in the operation). They have also regularly thwarted attacks.
This is deterrence by denial: by denying the attackers the gain they seek, the defenders are changing the attackers’ cost-benefit calculus. “You always have the right to self-defense,” Wang noted. “So if you are shot at, you or your defenders can shoot back.
That’s mandate for all the ships participating in Prosperity Guardian: they can shoot as soon as they see any threat emerging.” 60 Interview with the author, March 28, 2024. Retired Vice Admiral Andrew Lewis, who until 2021 commanded the US Navy’s Second Fleet and in an earlier posting commanded the US Navy’s Carrier Strike Group 12, described the situation as follows.
The Houthis’ attacks are essentially a culmination of the threats we’ve seen over the past 15 years. At the beginning of that period, we broadly saw terrorist and piracy threats. As things progressed, we saw the Houthis become more active.
As recently as nine years ago, when I was a carrier strike group commander, we were intercepting Iranian convoys of dhows that were transiting to either Oman or Yemen to go to Yemen with the weaponry the Houthis are now using to target vessels in the Red Sea and Bab el-Mandeb Strait. For a period of time, we intercepted these convoys and forced them to turn around, so the equipment wasn’t flowing through, but they continued to build up that capability, and that is the result we’re seeing now. 61 Interview with the author, March 13, 2024.
The fact that there was no global body policing Iran’s shipments of weapons through the Red Sea thus became the source of the dramatic threats to shipping in the Red Sea once the Houthis acquired enough weaponry to launch their attacks. Indeed, despite the launch of Prosperity Guardian, the Houthis’ attacks accelerated. On December 26, for example, US naval vessels and aircraft in the Red Sea shot down twelve one-way attack drones, three anti-ship ballistic missiles, and two land-attack cruise missiles within a period of ten hours.
62 U.S. Central Command (@CENTCOM), “U.
S. assets, to include the USS LABOON (DDG 58) and F/A-18 Super Hornets from the Eisenhower Carrier Strike Group, shot down twelve one-way attack drones, three anti-ship ballistic missiles, and two land attack cruise missiles in the Southern Red Sea that were fired by the Houthis over a 10 hour period which began at approximately 6:30 a.m.
(Sanaa time) on December 26. There was no damage to ships in the area or reported injuries,” Twitter, December 26, 2023, 2:36 p.m.
, https://twitter.com/CENTCOM/status/1739746985652158755 . Such lack of success would convince a conventional adversary to give up.
But the novel aspect of the Houthis’ campaign against shipping is not just their comparatively modern weaponry (including the fact that they’re the first non-state group to have fired anti-ship ballistic missiles) but also that the ability to harm merchant vessels is secondary in their cost-benefit calculus. “The difference between piracy and the Houthis is that piracy is criminality. It’s to make money,” said retired Vice Admiral Duncan Potts, who until 2018 was the UK armed forces’ director general of joint force development and previously commanded the EU’s ATALANTA counter-piracy mission.
“And like any other business model, if the cost and the risk gets too high, you just move elsewhere. But for the Houthis the attacks are not about money.” 63 Interview with the author, April 10, 2024.
The Houthis’ priority is not even to sink vessels, which is what a traditional adversary attacking vessels would intend. Instead, their top priority has turned out to be to gain global attention and to cause fear among shipping companies, their insurers, and their customers, and thus to gain a global platform. The Houthis’ cost-benefit calculus also differs from that of the West’s traditional adversaries, as they primarily use cheap drones and missiles.
An often-quoted cost per Houthi missile is $2,000. Simon Lockwood, head of shipowners at Willis Towers Watson, noted that it is these weapons’ relative lack of sophistication that—together with the Houthis’ sloppy research—causes the most fear in the shipping industry. “How do you cause a massive amount of disruption? You just create that level of uncertainty that causes companies in the maritime industry to say, ‘we can’t go into the Red Sea,’” he said.
“If I were that way inclined, I would laud the Houthis’ ability to create absolute mayhem with relatively unsophisticated weapons, just to scare off merchant vessels.” 64 Interview with the author, March 14, 2024. However, the Houthis’ current weapons are a significant improvement from the weaponry used by militias in the early 2000s.
The Limburg was attacked by a suicide bomber driving an explosive-laden small boat into the vessel’s hull. Today, by contrast, the Houthis have sophisticated missiles as well as relatively simple drones. “Improvements in technology are a key reason these attacks are happening,” Ringbakken noted.
“When I started in this job and even ten years into the job, my experts were telling me that for groups of terrorists and others to hit a moving target like a vessel is extremely difficult. Now the Houthis have proved that it’s quite easy. There’s technological development in targeting technology that has made it possible for groups like the Houthis to drag their equipment around on a lorry and then target and hit a ship far away out in the sea.
That was not possible a decade ago.” 65 Interview with the author, March 14, 2024. Even the best of these missiles and drones don’t reach the technological sophistication of those used by first-rate armed forces, and the Houthis’ drones only hit ships randomly.
But the combination is powerful. “The Houthis’ weapons are a mix of very, very advanced missiles and very, very cheap drones. It’s dangerous cocktail,” Wang said.
66 Interview with the author, March 28, 2024. The fact that a non-state group that has signed no maritime conventions and feels bound by no maritime rules has access to this dangerous cocktail is a serious threat to global shipping. Indeed, the drones and missiles cause fear among shipping companies, and thwarting them requires far more sophisticated—and far more expensive—technology.
Offensive missiles don’t need to be very precise, at least if the attacker’s objective is not to harm specific targets. By contrast, defensive missiles—whose task is to shoot down the offensive missiles—must be extremely precise. US Navy defensive missiles cost, on average, between $1.
5 million and $2.5 million each. 67 Wes Rumbaugh, “Cost and Value in Air and Missile Defense Intercepts,” Center for Strategic and International Studies, February 13, 2024, https://www.
csis.org/analysis/cost-and-value-air-and-missile-defense-intercepts . For the Houthis, $2,000-a-piece missiles supplied by Iran are a bargain, especially because the missiles spread fear in the shipping industry, regardless of whether they hit their intended target.
Despite Operation Prosperity Guardian’s efforts, the Red Sea has become too risky for many shipping lines and their insurers. By late December 2023, shipping traffic through the Red Sea had decreased by nearly 20 percent. 68 Bridget Diakun, “Red Sea Activity Down Nearly 20% after Containership Exodus,” Lloyd’s List, January 4, 2024, https://www.
lloydslist.com/LL1147824/Red-Sea-activity-down-nearly-20-after-containership-exodus . On January 3, the United States, UK, Germany, Italy, South Korea, and several other Western countries (and, again, Bahrain) issued a stern statement, warning the Houthis of consequences should the attacks continue: Ongoing Houthi attacks in the Red Sea are illegal, unacceptable, and profoundly destabilizing.
There is no lawful justification for intentionally targeting civilian shipping and naval vessels. Attacks on vessels, including commercial vessels, using unmanned aerial vehicles, small boats, and missiles, including the first use of anti-ship ballistic missiles against such vessels, are a direct threat to the freedom of navigation that serves as the bedrock of global trade in one of the world’s most critical waterways. These attacks threaten innocent lives from all over the world and constitute a significant international problem that demands collective action.
69 “A Joint Statement from the Governments of the United States, Australia, Bahrain, Belgium, Canada, Denmark, Germany, Italy, Japan, Netherlands, New Zealand, Republic of Korea, Singapore, and the United Kingdom,” White House, January 3, 2024, https://www.whitehouse.gov/briefing-room/statements-releases/2024/01/03/a-joint-statement-from-the-governments-of-the-united-states-australia-bahrain-belgium-canada-denmark-germany-italy-japan-netherlands-new-zealand-and-the-united-kingdom/ .
The Houthis—logically, according to their cost-benefit calculus—responded with a highly complex attack comprising Iranian-designed one-way attack drones, anti-ship cruise missiles, and an anti-ship ballistic missile. 70 “US CENTCOM Statement on 26th Houthi Attack on Commercial Shipping Lanes in the Red Sea,” US Central Command, January 9, 2024, https://www.centcom.
mil/MEDIA/STATEMENTS/Statements-View/Article/3639970/us-centcom-statement-on-26th-houthi-attack-on-commercial-shipping-lanes-in-the/ . Shooting them down required the efforts of F/A-18s from USS Dwight D. Eisenhower, USS Gravely (DDG 107), USS Laboon (DDG 58), USS Mason (DDG 87), and the Royal Navy’s HMS Diamond (D34).
71 Ibid. The fact that Iran supplies the drones and missiles and, in some cases, intelligence to the Houthis, is well-known both to maritime executives and to Western militaries. It would, however, be legally dubious and highly risky for Western armed forces to militarily punish Iran for the Houthis’ attacks.
“The maritime domain is unfortunately a welcome arena for escalation without making it state to state,” Ringbakken said. 72 Interview with the author, March 14, 2024. Indeed, the Houthis have demonstrated that they can keep escalating because the United States and other Western allies are loath to retaliate against Iran.
On January 11, the United States and UK, supported by Australia, Bahrain, Canada, and the Netherlands—operating as part of a new coalition operating in parallel with Prosperity Guardian—launched strikes against Houthi targets in Yemen. “These strikes are in direct response to unprecedented Houthi attacks against international maritime vessels in the Red Sea—including the use of anti-ship ballistic missiles for the first time in history,” President Joe Biden said in a statement. “These attacks have endangered US personnel, civilian mariners, and our partners, jeopardized trade, and threatened freedom of navigation.
” 73 “Statement from President Joe Biden on Coalition Strikes in Houthi-Controlled Areas in Yemen,” White House, press release, January 11, 2024, https://www.whitehouse.gov/briefing-room/statements-releases/2024/01/11/statement-from-president-joe-biden-on-coalition-strikes-in-houthi-controlled-areas-in-yemen/ .
Further strikes have followed; by the end of February, the United States and the UK had carried out strikes on an almost daily basis. 74 Phil Stewart and Idrees Ali, “US, British Forces Carry out More Strikes against Houthis in Yemen,” Reuters, February 25, 2024, https://www.reuters.
com/world/middle-east/us-british-forces-carry-out-additional-strikes-against-houthis-yemen-2024-02-24/ . Not even this punishment has convinced the Houthis to end their attacks. In early 2024, they instead expanded the scope of their attacks, targeting vessels linked to the United States and the UK in addition to those linked to Israel.
On January 18, for example, they launched two anti-ship ballistic missiles against a Marshall Islands-flagged, US-owned, Greek-operated tanker. 75 U.S.
Central Command (@CENTCOM), “Third Houthi Terrorists Attack on Commercial Shipping Vessel in Three Days: On Jan. 18 at approximately 9 p.m.
(Sanaa time), Iranian-backed Houthi terrorists launched two anti-ship ballistic missiles at M/V Chem Ranger, a Marshall Island-flagged, U.S.-Owned, Greek-operated tanker ship.
The crew observed the missiles impact the water near the ship. There were no reported injuries or damage to the ship. The ship has continued underway,” Twitter, January 18, 2024, 6:42 p.
m., https://twitter.com/CENTCOM/status/1748143745567010833 .
Since then, the United States and the Prosperity Guardian allies have thwarted Houthi drones, missiles, and anti-ship missile attacks on an almost daily basis, while the US- and UK-led strike coalition has continued its strikes against strategic installations in Houthi-held Yemeni territory. 76 Ibid. As before, the Houthis decide what constitutes links to the countries concerned, which puts every vessel at risk of attack.
“We can disagree with them and argue that a ship they’ve attacked is not linked to one of these three countries, but once the rocket has hit your ship, it’s too late,” Ringbakken noted. 77 Interview with the author, March 14, 2024. Lockwood added, “US links, UK links, Israeli links: that’s rubbish.
The attacks are about targeting shipping for effect, and it’s crippling shipping.” 78 Interview with the author, March 14, 2024. By April 2024, sixty-five countries’ interests had been affected by the campaign, according to the US Defense Intelligence Agency.
79 “Yemen: Houthi Attacks Placing Pressure on International Trade,” US Defense Intelligence Agency, 2024, 3, https://www.dia.mil/Portals/110/Images/News/Military_Powers_Publications/YEM_Houthi-Attacks-Pressuring-International-Trade.
pdf . Only ships linked to Russia and China have appeared safe. Indeed, in an effort to keep their vessels safe, by the beginning of 2024 some captains had adopted a strategy of incorrectly communicating to the Houthis that they had an all-Chinese crew.
On February 19, the EU announced the formation of another naval mission in the Red Sea. Operation Aspides, comprising France, Germany, Italy, and Belgium, would protect merchant vessels alongside Prosperity Guardian and the strike coalition. 80 Mared Gwyn Jones, “EU Launches Mission Aspides to Protect Red Sea Vessels from Houthi Attacks,” Euronews, February 19, 2024, https://www.
euronews.com/my-europe/2024/02/19/eu-launches-mission-aspides-to-protect-red-sea-vessels-from-houthi-attacks . The Houthis, meanwhile, appeared to continue sparing any vessels linked to Russia and China.
81 Sam Dagher and Mohammed Hatem, “Yemen’s Houthis Tell China, Russia Their Ships Won’t Be Targeted,” Bloomberg, March 21, 2024, https://www.bloomberg.com/news/articles/2024-03-21/china-russia-reach-agreement-with-yemen-s-houthis-on-red-sea-ships?sref=NeFsviTJ .
By March 2024, forty merchant vessels had been successfully attacked, thirty-four of which had sustained damage. 82 “Who Are the Houthis and Why Are They Attacking Red Sea Ships?” BBC, March 15, 2024, https://www.bbc.
com/news/world-middle-east-67614911 . A few weeks later, the rate of Houthi attacks appeared to have slowed. “Their pace of operations is not what it was,” US Air Force Lieutenant General Alexus Grynkewich, the top US Air Force commander for the Middle East, told a press conference.
83 Sam Chambers, “Washington Seeks New Ways to Deescalate Red Sea Shipping Crisis,” Splash 247, April 4, 2024, https://splash247.com/washington-seeks-new-ways-to-deescalate-red-sea-shipping-crisis . Grynkewich attributed the slowdown to the effect of the US strikes, which had curtailed the Houthis’ arsenal of drones and missiles.
84 Ibid. Crucially, despite a reduced arsenal, the Houthis appeared undeterred and kept up their missile and drone strikes. The US Central Command, communicating through its Twitter (X), reported Houthi attacks on a near-daily basis.
85 https://twitter.com/CENTCOM . Yet the United States seemed to have little confidence the strikes would fundamentally improve security for Red Sea shipping.
Grynkewich told reporters that Iran’s continued supply of weapons was a “complicating factor.” Indeed, in the second half of April, the attacks increased again. On April 26, for example, the Houthis launched three anti-ship ballistic missiles from Yemen into the Red Sea, where they nearly hit one vessel and struck another, an apparently erroneously targeted suspected shadow vessel.
86 U.S. Central Command (@CENTCOM), “April 26 CENTCOM Red Sea Update: At 5:49 p.
m. (Sanna time) on April 26, Iranian-backed Houthi terrorists launched three anti-ship ballistic missiles (ASBMs) from Houthi-controlled areas of Yemen into the Red Sea in the vicinity of MV MAISHA, an Antigua/Barbados flagged, Liberia operated vessel and MV Andromeda Star, a UK owned and Panamanian flagged, Seychelles operated vessel. MV Andromeda Star reports minor damage, but is continuing its voyage,” Twitter, April 26, 2024, 7:46 p.
m., https://twitter.com/CENTCOM/status/1784021287553135050 .
By the end of the month, the US Navy and allies had shot down Houthi drones and missiles or struck Houthi installations around 130 times, according to publicly known numbers. 87 Jonathan Lehrfeld, Diana Stancy and Geoff Ziezulewicz, “All the Houthi-US Navy Incidents in the Middle East (that We Know of),” Milit.
