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In 1781, President George Washington proclaimed that “without a decisive Naval force we can do nothing definitive. And with it, everything honorable and glorious.”
More on:
Today, an Iran-backed terrorist organization in Yemen, Ansar Allah, known colloquially as the Houthis, poses the toughest challenge to U.S. and allied maritime hegemony since we faced off against the Imperial Japanese Navy in the Pacific Theater of World War II.
Over the weekend, U.S. President Donald Trump posted on Truth Social: “To all Houthi terrorists, YOUR TIME IS UP, AND YOUR ATTACKS MUST STOP, STARTING TODAY. IF THEY DON’T, HELL WILL RAIN DOWN UPON YOU LIKE NOTHING YOU HAVE EVER SEEN BEFORE!” Trump also added a warning to Iran, saying that support for the Houthis needs to end now: “America will hold you fully accountable, and we won’t be nice about it!”
Since then, the U.S. military has conducted large-scale strikes on Houthi targets in Yemen, targeting the group’s senior leadership, training sites, command centers, and weapons facilities, and killing at least fifty-three people, according to the Houthi-run health ministry.
Even amid Trump’s claims that “they will be completely annihilated,” the Houthis remain defiant. The militant group’s foreign minister told Reuters that they now see themselves at war with the United States, meaning they’ll defend themselves “with all possible means, so escalation is likely.”
The once marginal group gained its international notoriety during the outbreak of the Yemeni civil war, which began in 2014. Fighting under the banner of “God Is Great, Death to America, Death to Israel, Curse on the Jews, Victory to Islam,” the Houthis emerged after October 7, 2023, as one of the Middle East’s most influential non-state actors—first firing cruise missiles at Israel, then declaring any Israel-linked ship a target.
More on:
In a bid to show solidarity with Hamas and bring an end to Israeli military operations in Gaza, the Houthis launched one-way attack drones and missiles almost daily at U.S. Navy vessels and other countries’ civilian ships transiting the Red Sea. The Houthis’ strikes ushered in a crisis in the Red Sea and the Gulf of Aden’s Bab al-Mandeb Strait, dramatically disrupting business as usual in the passage. There was a brief pause in attacks in January of this year, which coincided with the cease-fire between Israel and Hamas.
When the Houthis first started attacking ships in the Red Sea, the United States took a relatively restrained approach. U.S. President Joe Biden didn’t re-designate the Houthis as a foreign terrorist organization in response to the attacks and placed tight restrictions on the U.S. military’s ability to target Houthi leaders and infrastructure. The administration feared regional escalation that might have put U.S. partners against one another, and that Yemen would plunge back into its deadlocked civil war with significant humanitarian implications.
This is not to say that the United States refrained from fighting back against the Houthis. The International Institute for Strategic Studies reported that the United States and its partners struck the Houthis more than 260 times last year. Those strikes, however, stopped short of trying to decimate Houthi leadership and rank and file. Instead, they focused on Houthi military equipment being used to target ships in the Red Sea. These operations degraded the Houthis’ operational tempo and destroyed significant portions of their long-range weapon stockpiles, but they didn’t put an end to the Houthis’ Red Sea campaign.
Since October 7, 2023, the Houthis, once thought of as a rag-tag militia, have rapidly acquired, enhanced, and deployed advanced military technologies to target ships. Their arsenal, which is smuggled into the country piece by piece from Iranian and Iranian-aligned suppliers in the region, now includes many modified Iranian anti-ship ballistic missiles, anti-ship cruise missiles, unmanned aerial vehicles, and unmanned surface vessels.
The Houthis have learned to assemble and modify these weapons with more advanced guidance systems and other modifications in covert armories, often buried deep underground, throughout northern and eastern Yemen. And they have learned to track and target maritime vessels using radar, satellite imagery, publicly available ship transponder data, and other means. All in all, the Houthis have demonstrated world-class, innovative anti-surface warfare capabilities—including the first-ever combat employment of an anti-ship ballistic missile in early 2024.
By the numbers, the Houthis have targeted U.S. warships more than 170 times and commercial vessels 145 times, according to the Department of Defense. Although the Houthis have yet to hit a U.S. Navy vessel, they have sunk two commercial vessels and killed four mariners. The Department of Defense also revealed recently that the U.S. military has expended upwards of $1 billion dollars as part of its efforts to protect vessels in the Red Sea—an exponentially higher sum than the cost of the Houthis’ offensive kit—laying bare the U.S. military’s vulnerability to asymmetric warfare and stretching an already strained U.S. defense industrial base to produce more air defense missiles.
The Houthis also seized a ship, the Galaxy Leader, in November 2023, keeping sailors from Bulgaria, Mexico, the Philippines, Romania, and Ukraine captive for fourteen months. They turned the ship into a tourist attraction which, for roughly a dollar, visitors could tour—a prize in their fight against the West. They released the ship’s crew in January of this year.
Human casualties and property damage aside, the broader impact of the Houthis campaign is on global trade. The Houthis have gravely undermined freedom of navigation in the Red Sea, especially in the Bab al-Mandeb Strait, which connects the Red Sea to the Gulf of Aden, by forcing many ships to reroute. Passage through the Red Sea and the Suez Canal is the quickest maritime route that connects Europe and Asia. While traffic fluctuates throughout the year, some 12 percent of global trade—totaling well over $1 trillion worth of goods per year—has typically transited through the passage.
As a result of Houthi attacks, The Economist estimates that shipments through the Red Sea are down 70 percent with many choosing to route instead around southern Africa’s Cape of Good Hope, adding some 3,500 nautical miles and at least ten days of travel time. It is the biggest disruption to international trade since COVID-19 pandemic.
The Houthis are not equal opportunity offenders. To secure safe passage for their maritime cargoes and undermine the United States’ regional interests, China and Russia have struck a variety of bargains with the Houthis.
In China’s case, the U.S. intelligence community and Treasury Department uncovered a complex web of shell companies, which funnel weapons manufacturing equipment and dual-use electronic components to the Houthi arsenal. In exchange, the Houthis avoid targeting Chinese-flagged vessels. Some 60 percent of all Chinese exports to Europe transit the Red Sea.
Despite a few mishaps, including a March 2024 incident in which Houthi anti-ship ballistic missiles struck a Chinese owned and operated oil tanker, the quid pro quo has proved quite effective in assuring the unimpeded flow of Chinese cargoes through the Suez Canal, which gives Chinese shipping companies a leg up against their U.S.-aligned competitors. As a result, Chinese shipping companies’ share of all Suez traffic has increased by nearly 25 percent since October 2023.
The Suez Canal is also a critical chokepoint for the Russian economy. Oil exports from Russia made up almost 70 percent of Suez southbound oil traffic in 2023, up from 23 percent in 2021, which was largely headed for India and China, according to the U.S. Energy Information Administration. Hence the Russians’ decision to quietly provide vital satellite imagery for targeting purposes in exchange for the safe passage of their vessels.
China and Russia’s support for the Houthis likewise extends to the United Nations, where both countries abstained from a January 2024 Security Council resolution sponsored by the United States and Japan that condemned the Houthi attacks on ships.
For clients unwilling or unable to provide military, intelligence, or diplomatic support, the Houthis now operate a black market “pay to play” service whereby maritime traders transfer funds to the group in exchange for safe passage. The Houthis are nothing if not entrepreneurial when it comes to funding their activities. As Dov Zakheim wrote this morning, the Houthis are the new Barbary pirates.
Of course, this is hardly the first time that transit through the Red Sea and Suez Canal has been disrupted—most recently by a container ship that ran aground in 2021 which cost as much as $15 million a day in losses. But that container ship was grounded for six days—it did not disrupt global trade for sixteen months.
With the degradation of Hamas and Hezbollah, the Houthis stand out as one of Iran’s proxies that continues to pose a serious threat to U.S. interests in the region. But the Houthis’ assault on global commerce and allied navies has proven entirely ineffective at advancing their grand strategic goal of bringing an end to Israeli military operations in Gaza. To the contrary, Israeli strikes and ground operations in Gaza resumed this week in full force and with no clear path to restoring a cease-fire.
With Iran on its back foot and Trump’s determination to bring the full capabilities of the U.S. military to bear against the Houthis, Ansar Allah’s days running roughshod in the Red Sea may be numbered. U.S. leadership in maintaining the freedom of navigation that is central to U.S. economic and national security is very much at stake.
The Siege of the Red Sea
The U.S. military continues to conduct large-scale strikes on Iran-backed Houthi targets in Yemen to counter their assault on global commerce and attempts to weaken Israel.
March 21, 2025 3:12 pm (EST)
- Article
- Current political and economic issues succinctly explained.
Sign up to receive CFR President Mike Froman’s analysis on the most important foreign policy story of the week, delivered to your inbox every Friday afternoon. Subscribe to The World This Week.
In 1781, President George Washington proclaimed that “without a decisive Naval force we can do nothing definitive. And with it, everything honorable and glorious.”
More on:
Today, an Iran-backed terrorist organization in Yemen, Ansar Allah, known colloquially as the Houthis, poses the toughest challenge to U.S. and allied maritime hegemony since we faced off against the Imperial Japanese Navy in the Pacific Theater of World War II.
Over the weekend, U.S. President Donald Trump posted on Truth Social: “To all Houthi terrorists, YOUR TIME IS UP, AND YOUR ATTACKS MUST STOP, STARTING TODAY. IF THEY DON’T, HELL WILL RAIN DOWN UPON YOU LIKE NOTHING YOU HAVE EVER SEEN BEFORE!” Trump also added a warning to Iran, saying that support for the Houthis needs to end now: “America will hold you fully accountable, and we won’t be nice about it!”
Since then, the U.S. military has conducted large-scale strikes on Houthi targets in Yemen, targeting the group’s senior leadership, training sites, command centers, and weapons facilities, and killing at least fifty-three people, according to the Houthi-run health ministry.
Even amid Trump’s claims that “they will be completely annihilated,” the Houthis remain defiant. The militant group’s foreign minister told Reuters that they now see themselves at war with the United States, meaning they’ll defend themselves “with all possible means, so escalation is likely.”
The once marginal group gained its international notoriety during the outbreak of the Yemeni civil war, which began in 2014. Fighting under the banner of “God Is Great, Death to America, Death to Israel, Curse on the Jews, Victory to Islam,” the Houthis emerged after October 7, 2023, as one of the Middle East’s most influential non-state actors—first firing cruise missiles at Israel, then declaring any Israel-linked ship a target.
More on:
In a bid to show solidarity with Hamas and bring an end to Israeli military operations in Gaza, the Houthis launched one-way attack drones and missiles almost daily at U.S. Navy vessels and other countries’ civilian ships transiting the Red Sea. The Houthis’ strikes ushered in a crisis in the Red Sea and the Gulf of Aden’s Bab al-Mandeb Strait, dramatically disrupting business as usual in the passage. There was a brief pause in attacks in January of this year, which coincided with the cease-fire between Israel and Hamas.
When the Houthis first started attacking ships in the Red Sea, the United States took a relatively restrained approach. U.S. President Joe Biden didn’t re-designate the Houthis as a foreign terrorist organization in response to the attacks and placed tight restrictions on the U.S. military’s ability to target Houthi leaders and infrastructure. The administration feared regional escalation that might have put U.S. partners against one another, and that Yemen would plunge back into its deadlocked civil war with significant humanitarian implications.
This is not to say that the United States refrained from fighting back against the Houthis. The International Institute for Strategic Studies reported that the United States and its partners struck the Houthis more than 260 times last year. Those strikes, however, stopped short of trying to decimate Houthi leadership and rank and file. Instead, they focused on Houthi military equipment being used to target ships in the Red Sea. These operations degraded the Houthis’ operational tempo and destroyed significant portions of their long-range weapon stockpiles, but they didn’t put an end to the Houthis’ Red Sea campaign.
Since October 7, 2023, the Houthis, once thought of as a rag-tag militia, have rapidly acquired, enhanced, and deployed advanced military technologies to target ships. Their arsenal, which is smuggled into the country piece by piece from Iranian and Iranian-aligned suppliers in the region, now includes many modified Iranian anti-ship ballistic missiles, anti-ship cruise missiles, unmanned aerial vehicles, and unmanned surface vessels.
The Houthis have learned to assemble and modify these weapons with more advanced guidance systems and other modifications in covert armories, often buried deep underground, throughout northern and eastern Yemen. And they have learned to track and target maritime vessels using radar, satellite imagery, publicly available ship transponder data, and other means. All in all, the Houthis have demonstrated world-class, innovative anti-surface warfare capabilities—including the first-ever combat employment of an anti-ship ballistic missile in early 2024.
By the numbers, the Houthis have targeted U.S. warships more than 170 times and commercial vessels 145 times, according to the Department of Defense. Although the Houthis have yet to hit a U.S. Navy vessel, they have sunk two commercial vessels and killed four mariners. The Department of Defense also revealed recently that the U.S. military has expended upwards of $1 billion dollars as part of its efforts to protect vessels in the Red Sea—an exponentially higher sum than the cost of the Houthis’ offensive kit—laying bare the U.S. military’s vulnerability to asymmetric warfare and stretching an already strained U.S. defense industrial base to produce more air defense missiles.
The Houthis also seized a ship, the Galaxy Leader, in November 2023, keeping sailors from Bulgaria, Mexico, the Philippines, Romania, and Ukraine captive for fourteen months. They turned the ship into a tourist attraction which, for roughly a dollar, visitors could tour—a prize in their fight against the West. They released the ship’s crew in January of this year.
Human casualties and property damage aside, the broader impact of the Houthis campaign is on global trade. The Houthis have gravely undermined freedom of navigation in the Red Sea, especially in the Bab al-Mandeb Strait, which connects the Red Sea to the Gulf of Aden, by forcing many ships to reroute. Passage through the Red Sea and the Suez Canal is the quickest maritime route that connects Europe and Asia. While traffic fluctuates throughout the year, some 12 percent of global trade—totaling well over $1 trillion worth of goods per year—has typically transited through the passage.
As a result of Houthi attacks, The Economist estimates that shipments through the Red Sea are down 70 percent with many choosing to route instead around southern Africa’s Cape of Good Hope, adding some 3,500 nautical miles and at least ten days of travel time. It is the biggest disruption to international trade since COVID-19 pandemic.
The Houthis are not equal opportunity offenders. To secure safe passage for their maritime cargoes and undermine the United States’ regional interests, China and Russia have struck a variety of bargains with the Houthis.
In China’s case, the U.S. intelligence community and Treasury Department uncovered a complex web of shell companies, which funnel weapons manufacturing equipment and dual-use electronic components to the Houthi arsenal. In exchange, the Houthis avoid targeting Chinese-flagged vessels. Some 60 percent of all Chinese exports to Europe transit the Red Sea.
Despite a few mishaps, including a March 2024 incident in which Houthi anti-ship ballistic missiles struck a Chinese owned and operated oil tanker, the quid pro quo has proved quite effective in assuring the unimpeded flow of Chinese cargoes through the Suez Canal, which gives Chinese shipping companies a leg up against their U.S.-aligned competitors. As a result, Chinese shipping companies’ share of all Suez traffic has increased by nearly 25 percent since October 2023.
The Suez Canal is also a critical chokepoint for the Russian economy. Oil exports from Russia made up almost 70 percent of Suez southbound oil traffic in 2023, up from 23 percent in 2021, which was largely headed for India and China, according to the U.S. Energy Information Administration. Hence the Russians’ decision to quietly provide vital satellite imagery for targeting purposes in exchange for the safe passage of their vessels.
China and Russia’s support for the Houthis likewise extends to the United Nations, where both countries abstained from a January 2024 Security Council resolution sponsored by the United States and Japan that condemned the Houthi attacks on ships.
For clients unwilling or unable to provide military, intelligence, or diplomatic support, the Houthis now operate a black market “pay to play” service whereby maritime traders transfer funds to the group in exchange for safe passage. The Houthis are nothing if not entrepreneurial when it comes to funding their activities. As Dov Zakheim wrote this morning, the Houthis are the new Barbary pirates.
Of course, this is hardly the first time that transit through the Red Sea and Suez Canal has been disrupted—most recently by a container ship that ran aground in 2021 which cost as much as $15 million a day in losses. But that container ship was grounded for six days—it did not disrupt global trade for sixteen months.
With the degradation of Hamas and Hezbollah, the Houthis stand out as one of Iran’s proxies that continues to pose a serious threat to U.S. interests in the region. But the Houthis’ assault on global commerce and allied navies has proven entirely ineffective at advancing their grand strategic goal of bringing an end to Israeli military operations in Gaza. To the contrary, Israeli strikes and ground operations in Gaza resumed this week in full force and with no clear path to restoring a cease-fire.
With Iran on its back foot and Trump’s determination to bring the full capabilities of the U.S. military to bear against the Houthis, Ansar Allah’s days running roughshod in the Red Sea may be numbered. U.S. leadership in maintaining the freedom of navigation that is central to U.S. economic and national security is very much at stake.
