Striking Back: Analyzing the US-led Response to Houthi Red Sea Attacks
In mid-March 2025, the United States dragged Yemen’s Houthi rebels back into the global spotlight with a series of preemptive strikes on Houthi missile capabilities, and it seems as though this temporarily dormant conflict is suddenly far from over. This article, Part 1 of a series on the ongoing Red Sea Crisis, examines the timeline, effectiveness, and geopolitical context of US, UK, and Israeli military strikes on Houthi rebel forces in Yemen since October 2023 using contemporary conflict data.
Bottom Line Up Front:
Across 2024, US, UK, and Israeli strikes against Houthi forces in Yemen contributed to a reduction in the rate of Houthi attacks on maritime shipping in the Red Sea.
The reluctance of shipping firms to return to operations in the Red Sea en masse suggests that simply halting Houthi attacks on merchant shipping may be insufficient to restore the perception of stability.
With the confidence of shipping firms remaining low even as Houthi attacks have stalled, Houthi actions remain a playbook for malign actors in the vicinity of maritime chokepoints worldwide.
The Red Sea Crisis in Brief
Since late 2023, Houthi rebels in Yemen have prosecuted a regional campaign of sea denial in the Red Sea, Bab al-Mandab Strait, and the Gulf of Aden. Although nominally conducted in response to US support of Israeli military operations in Gaza, this campaign has formed a part of the decades-long Iranian-led axis of resistance to Israel and the West in the region. On October 19, 2023, the Houthis opened their campaign by launching several salvos of one-way attack drones and land-attack cruise missiles over the Red Sea, many of which were intercepted by the USS Carney (DDG-64) in what the US Navy described as “the most intense combat engagement by a U.S. Navy warship since WWII.”
In November 2023, the rebels seized the Galaxy Leader, a British-owned cargo ship, taking its crew hostage and commencing the series of attacks on merchant shipping that would continue through the next year. In response, the United States announced the launch of Operation Prosperity Guardian, a multi-partner initiative to reestablish the security of maritime trade in the Red Sea and Gulf of Aden. In January 2024, the United States and United Kingdom carried out a series of air and naval strikes against Houthi targets, with further strikes by the United States and partners conducted throughout the remainder of the year.
However, these strikes did not halt Houthi aggression. Notable Houthi attacks on merchant shipping throughout 2024 included the respective sinkings of the Rubymar bulk carrier and the MV Tutor coal carrier in March and June, alongside the near-destruction of the oil tanker MV Sounion, fortuitously towed to safety by a EUNAVFOR task force before its contents could cause an environmental catastrophe.
In January 2025, coinciding with an announced ceasefire between Israel and Hamas, the Houthis announced that they would pause attacks in the Red Sea, and released the crew of the Galaxy Leader. However, the group reversed their position in early March, prompting sudden US military strikes on March 15, apparently conducted to degrade the Houthi fires capabilities before attacks on shipping could resume. Where the conflict goes from here remains uncertain.
Global Economic Consequences of the Red Sea Crisis
Houthi attacks on merchant shipping in the Red Sea have emphasized the dependencies of efficient global trade on the security of key maritime choke points. The crisis has caused dozens of major shipping firms to alter their operations, with many firms choosing to navigate around the Cape of Good Hope rather than accept the physical risk and surging insurance premiums currently charged for Red Sea voyages. As of 2025, many shipping firms are still taking a wait-and-see approach before returning to operations in the region due to continued uncertainty around regional security, with the firms’ operations now aligned to the status quo for at least the next fiscal year. Both container and tanker ship passages through the Red Sea remain at levels far below 2023 baselines, as shown in the graphic below.
With many firms still committed to avoiding the Red Sea in the near term, thereby accepting higher operating expenses associated with longer, less efficient routes, shipping customers have continued to bear the additional cost. For example, 40-foot-equivalent (FEU) container shipping rates surged across 2024 as constant demand for goods collided with the inefficiencies caused by the Red Sea conflict, as shown in the graphic below. As of this writing, FEU rates have declined as firms have adjusted to their new operational constraints, but rates still remain elevated above 2023 levels.
Analysis of US, UK, and Israeli Strikes
Using curated data from the Yemen Conflict Observatory, a special project of the Armed Conflict Location & Event Data (ACLED) initiative, we can compare the volume of Houthi attacks against maritime shipping against the volume of the US-led international response. This analysis also pairs the uniquely identified merchant vessels in the ACLED dataset with ship metadata from the Electronic Quality Shipping Information System (Equasis) to better understand the characteristics of the ships ultimately targeted by the Houthis.1
The graphic below shows the merchant ships attacked by the Houthis over the course of 2023 and 2024 by dead weight tonnage (DWT), a measure of the total carrying capacity of merchant ships. No clear patterns emerge in target selection by either ship type or size, although the rate of attacks appears to decline beyond August 2024, with the plot becoming increasingly sparse by the end of the year.
The declining rate of Houthi attacks on merchant shipping becomes more clear when we compare the number of cumulative Houthi attacks against cumulative US, UK, and Israeli strikes. As shown in the graphic below, although the Houthis conducted frequent attacks on shipping in 2024, with a noticeable acceleration over the summer months, the accumulation rate of attacks ultimately flattened towards the end of the year.
Meanwhile, US-led strikes built up rapidly early in 2024, and after a months-long deceleration in the spring, continued at a relatively stable rate for the remainder of the year as the Houthi attack rate began to level out. This analysis suggests that Houthi capabilities and capacity may have been slowly degraded by sustained US-led strikes over the course of 2024, with the Houthis ultimately ending the year in a weaker position relative to the start.
However, it is challenging to disentangle the specific contribution of these strikes from the contributions of other geopolitical developments. Examples of other potential contributors include the decimation of Hezbollah leadership and the sudden collapse of the Assad regime, both of which may have convinced Iran that a regenerative break in hostility in the region would be to its benefit. Likewise, reports emerged in late 2024 that exposed Russia’s direct operational support to the Houthis, including supplying the militia with targeting data on merchant ships, and it is possible that Russia suspended or reduced this support to avoid provoking the incoming US administration. The true relationship between the US-led strikes and the deceleration in Houthi attacks therefore remains unknown.
Last year, plenty of debate surfaced as to whether the US strategy for returning stability to the Red Sea via limited strikes could ever prove successful. If the United States primarily aimed to halt attacks on merchant shipping, these strikes outwardly appear to have been a success – for now. However, as shipping firms have indicated this week, it may take a lot more than a cessation of attacks on merchant ships to reassure shipping companies and the firms that insure them that their ships and crews are safe. The possibility of violence against shipping, however remote, is a powerful deterrent to commercial firms, and US hard power methods seem ill-suited to meet this asymmetry. For each day that massive international companies believe a major global trade corridor is too unsafe to navigate, the Houthis and Iran chip away a small fragment from the deterrent credibility of the United States. Now with US strikes on the Houthis resuming, and with another aircraft carrier headed to the region as of this writing, it seems any return to perceived stability in the Red Sea remains in the distant future.
A note on methodology: I present Houthi attacks on merchant shipping as those entries in the ACLED data which feature Houthi military forces as one of the actors, and for which the “Notes” entry contains a reference to one or more specific International Maritime Organization (IMO) numbers (an IMO number is seven-digit number that uniquely and permanently identifies a merchant ship). These event entries include both attacks that struck or landed in the vicinity of merchant ships, alongside interception events in which the target was believed to be a specific merchant ship. In many cases, several salvos may be included as part of a single entry. For this reason, and because I only count attacks associated with specific IMO numbers, these figures likely undercount the total Houthi attack events on merchant shipping. I present US-led strikes as those ACLED entries that feature the United States or its partners (United Kingdom, Israel, France, Germany, Denmark, Greece, Italy, and Saudi Arabia) as the instigating actor, and which include Houthi military forces as the target actor. Where appropriate, I also filter these entries to separate interception events from offensive attacks on Houthi forces.
Preview Photo Source: Truman's Deployment, Petty Officer 2nd Class Darren Cordoviz, DVIDS, 3/16/2025.
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Pretty damn good article 👍
A really good analysis - thanks very much.