PARIS — France’s maritime commander for the Indian Ocean defended the use of million-euro missiles to down drones used by Yemen’s Houthi rebels to attack shipping in the Red Sea, citing the value of the lives and assets protected, and the sophistication of the threat.

The Languedoc frigate patrolling in the southern Red Sea in December shot down multiple drones using Aster 15 missiles, at a cost that defense analysts estimate at around €1 million (U.S. $1.1 million) per missile. The British Royal Navy’s HMS Diamond has also used the missiles to fend of drone attacks in the area.

The proliferation of cheap drones on the battlefield poses a challenge to Western navies, whose missile-based air defense tends to be effective but pricey. The economic calculus of ultra-capable interceptors, designed to counter expensive expensive anti-ship missiles or manned aircraft, quickly loses its appeal against drones costing thousands of dollars, analysts have warned.

“The cost is not that of the missile we use, but the cost of what we protect,” Vice Adm. Emmanuel Slaars said in response to questions by Defense News at Jan. 11 press briefing here. Slaars said there was “no doubt” the Languedoc was targeted in an incident early December when the warship used MBDA’s Aster 15 missiles to shoot down two drones coming from the direction of Yemen.

The commander said not all drones used by the Houthi’s are cheap loitering munitions, and some variants used for target observation are “quite sophisticated.” Downing reconnaissance drones can head off a more lethal attack, Slaars said.

The Houthi rebels are using shipping-tracking data to identify potential targets, then fly observation drones to scout vessels before attacking them with drones and anti-ship missiles, according to Slaars. The drone and missile technology being used by the Houthis is from Iran, “there’s no secret there,” the vice admiral said.

The Languedoc has been escorting French-flagged vessels or ships with “French interests” through the Red Sea independent of Operation Prosperity Guardian, Slaars said. When not on escort duty, the frigate is available to patrol zones assigned as part of the U.S.-led operation, though the Languedoc remains under French command at any time.

Italy is also operating a vessel in the Red Sea, while a Greek ship hasn’t arrived yet, according to Slaars, who is the commander of the French forces stationed in the United Arab Emirates as well as of the European-led maritime awareness mission in the Strait of Hormuz.

Rudy Ruitenberg is a Europe correspondent for Defense News. He started his career at Bloomberg News and has experience reporting on technology, commodity markets and politics.

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