The Houthis Proved Ballistic Missiles Can Hit Moving Vessels

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The Houthis Proved Ballistic Missiles Can Hit Moving Vessels

The Houthi conflict has provided some important data points for military analysts. It turns out that ballistic missiles can indeed hit vessels in motion, though not reliably. U.S. warships can block such missiles very well, with a dozen interceptions to their credit so far

Houthi missile attacks in the Red Sea region have aggravated regional tensions and disrupted global trade. They consequently pose challenges for trading nations generally and the U.S. in particular. However, those strategic impacts have been achieved despite the lackluster performance of their weapons against both land and sea targets.

Missing Israel

Houthi militants began launching missiles and drones across the Red Sea toward Israel last October. But none of the projectiles they’ve reportedly fired since then have struck that country, though one did injure six Egyptians. U.S. or Israeli forces instead intercepted most.

That zero percent hit rate is abysmal, though not unprecedented. Only about three percent of Hamas rockets struck Israeli targets back in 2014, thanks to Israel’s persistent airstrikes and Iron Dome interceptors. But Hamas rocketry improved considerably after that.

The Houthis did notably trigger the first hostile engagements in space. Five of their ballistic missiles were shot down by Israeli Arrow interceptor missiles high above the Earth’s atmosphere.

Also noteworthy were the interceptions of Israel-bound projectiles by Egypt and Saudi Arabia. Those demonstrated how a Middle East Air Defense alliance could someday protect the region if the countries could agree to cooperate.

Denting Ships

Houthi attacks at sea have gone slightly better. Since November, they’ve launched hundreds of cruise missiles, ballistic missiles, and drones at ships in the Red Sea or Gulf of Aden.

The cruise missiles were expected. Other countries have used those standard naval weapons to sink ships, ranging from Israel’s Eilat in 1967 to Russia’s Moskva in 2023. Historically, their hit rate has been about 90 percent against commercial vessels, though only 25 percent against actively defending warships.

The Houthi performance has been similar. The one cruise missile they launched at a tanker hit and ignited a fire. And while the four they shot at warships were all intercepted, one (i.e., 25 percent) came within seconds of striking a U.S. destroyer.

However, I estimate only about 5 percent of Houthi projectiles have been sea-skimming cruise missiles. Instead, they’ve mostly launched high-trajectory ballistic missiles and slow-flying drones.

Their drone use at sea builds on what we’ve seen in Ukraine on land. By my count, the Houthi drones have hit an estimated 67 percent of the merchant ships they’ve targeted, but none of the warships.

By contrast, their use of ballistic missiles against ships at sea constitutes a world first. (Ukraine has used them against Russian ships in the harbor.) But they’ve hit only an estimated 30 percent of their commercial targets and none of their military ones.

And even their hits have done relatively little damage. Several of the eighteen vessels reported struck so far have caught fire. But only one needed to be evacuated, and no casualties have been reported.

Ironically, their most successful ship attack so far involved simply hijacking a transport.

Given the mediocre drone and ballistic missile results, it’s puzzling that the Houthis haven’t fired more cruise missiles. Are they saving them for later surprises, or do they not have many at all?

Strategic Impacts

Not surprisingly, these misguided missiles haven’t forced a halt to Israel’s Gaza invasion. On the contrary, they assisted that country by battle-testing its Arrow interceptors against live targets. That could help sell the weapons to customers like Germany.

But the Houthis’ tactical failings haven’t prevented other strategic successes.

The symbolism of attacking Israeli communities and U.S. vessels has presumably impressed their domestic and foreign supporters.

More concretely, their maritime bombardment has pushed shipping companies to avoid the Red Sea and send 42 percent less freight through the Suez Canal. That has hurt Egypt’s economy while increasing transportation costs for European and Asian businesses.

The economic pain has triggered naval reactions, and not just from the U.S. and Israel. France and Britain have deployed warships to the Red Sea, while India and Pakistan have put theirs in the Arabian Sea.

Those defensive missions have intercepted many Houthi weapons but expended millions of dollars’ worth of ammo in doing so.

Next came airstrikes, which the United States and UK began in January. But because the Houthis keep shooting, shipping companies still aren’t reassured. And Washington desperately wants to avoid further escalation.

These multinational challenges with Houthi missiles consequently resemble Israel’s difficulties with Hamas’ rockets. For years, Israel has used interceptors to block rockets overhead and airstrikes to destroy them on the ground. But neither measure has ever reduced the rocket fire: doing that required bloody ground operations in Gaza, like the current one.

Further outcomes

One interesting result of this situation is that the European Union is organizing a naval expedition to the Red Sea, separate from the U.S.-led mission already there. That experience with operational independence could prove valuable if mercurial Donald Trump again becomes U.S. president.

The EU mission will give warships already there a chance to rest and reload. However, since it is purely defensive, it can only buy time to find another solution. And it’s a calculated risk: Houthi weapons haven’t struck any warships yet, but it’s only a matter of time.

This Red Sea conflict also has implications in the China Sea. China, like the Houthis, has an arsenal of anti-ship ballistic missiles. And their “carrier killer” potential might deter U.S. warships from intervening in any conflict with Taiwan.

However, whether such missiles could realistically hit warships maneuvering at sea is unclear. Conversely, whether those warships could intercept such high-altitude ballistic missiles as opposed to sea-level cruise missiles.

The Houthi conflict has provided some tentative answers. It turns out that ballistic missiles can indeed hit vessels in motion, though not reliably. U.S. warships can block such missiles very well, with a dozen interceptions to their credit so far.

So, although the Houthis missiles have been militarily mediocre, they’ve given naval staff around the world much to ponder.

About the Author 

Michael J. Armstrong is an associate professor of operations research at Brock University in Canada. He has researched both naval missile warfare and Israeli rocket defenses.

Image: U.S. Navy Flickr.