Carrier Gap Increases the Red Sea’s Vulnerability to Houthi Attacks

On June 22, the Defense Department announced that the Dwight D. Eisenhower Carrier Strike Group (IKE CSG) had departed the Red Sea after a nearly eight-month deployment-a decision carried out despite the fact that Houthi forces in Yemen continue to attack international shipping. Before returning home, the IKE CSG is briefly visiting the East Mediterranean to reassure Israel, deter Hezbollah, and prevent further escalation on the Lebanon border. Its replacement, the Theodore Roosevelt Carrier Strike Group (TR CSG), does not depart the Indo-Pacific for the Middle East until next week, after conducting the trilateral Freedom Edge exercise with Japan and South Korea.

The absence of a carrier strike group in the Red Sea for two to three weeks (accounting for transit time) sends a worrisome signal at a time when the Houthis are increasing the tempo and severity of their attacks on commercial and naval vessels. Although destroyers assigned to the IKE CSG might stay behind to provide temporary drone and missile defense capabilities, the gap before the TR CSG arrives will require heavy reliance on limited assets-destroyers, ground-based aircraft, and intelligence, surveillance, and reconnaissance capabilities-to defend a critical shipping lane. This raises the need for a temporary surge of partner forces or, failing that, a combination of urgent stopgap measures and heightened diplomatic coordination.

Departing Capabilities, Growing Threats

The Red Sea has lost several formidable capabilities with the departure of the IKE CSG: the carrier USS Dwight D. Eisenhower and its air squadrons; the guided missile cruiser USS Philippine Sea, which can launch cruise missiles or long-range air-defense missiles; and at least part of a destroyer squadron that provides a defensive umbrella against air, surface, undersea, and ballistic missile attacks. Beginning in November, the IKE CSG played a crucial role in countering the Houthi antishipping threat, which first emerged that month in response to the Gaza war. It defended against several attacks by Houthi ballistic missiles, drones, and surface vessels, conducted rescue and lifesaving measures for vessels and mariners in distress, and launched strikes in Yemen to disrupt and degrade Houthi capabilities used in such attacks. Most recently, the IKE CSG assisted the crews of two targeted vessels: the Tutor, a Liberian-flagged, Greek-owned cargo ship that sank after it was attacked by the Houthis multiple times on June 12, and the Verbena, a Palauan-flagged, Ukrainian-owned, Polish-operated cargo ship struck on June 13.

Such attacks have worsened despite two separate defensive coalitions operating in the Red Sea-the U.S.-led Operation Prosperity Guardian and the European Union Naval Force Aspides-and several rounds of U.S. and British-led counterstrikes against the Houthis, often with support from Australia, Bahrain, Canada, Denmark, the Netherlands, and New Zealand. In all, the Houthis have launched about 190 attacks since November 19 (see The Washington Institute's maritime incident tracker for full details on these attacks).

More to the point, the risk of successful attacks may increase now that the IKE CSG is no longer there to intercept them. During the strike group's deployment, the United States, Britain, and various coalition partners downed over 200 missiles and drones aimed at a wide variety of targets, including the CSG itself. For their part, the four frigates and one maritime surveillance aircraft operated by Aspides shot down over a dozen drones and ballistic missiles and provided assistance to over 160 ships.

Recommendations

Because the Houthis are unlikely to ignore the vulnerabilities created by IKE's departure, U.S. and coalition assets in the region will need to implement stopgap measures until the TR CSG arrives. In particular, Washington should focus on steps that maintain pressure against the Houthis while balancing deterrence measures in the East Mediterranean.

The assets most needed to cover this gap are frigates, destroyers, and other maritime or air units capable of intercepting Houthi missiles and drones. They must also be able to assist vessels and mariners in distress in the event of successful attacks. And whatever forces are present in the area, the United States should be prepared to provide them with intelligence, early warning, and targeting support.

Washington should also strongly encourage international partners to deepen their cooperation and protect the global shipping industry by surging their own assets into the region. To be sure, the United States should be clear-eyed about partners' potential willingness to commit substantial assets-or any assets at all. Pressuring them to act is still important, however, especially in the case of European and Arab partners who are most affected by the transit delays, ship damage, and other costs inflicted by the Houthis.

The commander of Aspides has publicly argued for surging EU assets, but European capitals may be reticent to do so without further assurances that the United States is committed to prioritizing the counter-Houthi mission. They also face domestic constraints on resourcing and prioritization as well as political sensitivities surrounding the Gaza war, making them wary of backlash at home.

Hence, Washington should reassure its coalition partners in private while publicly warning the Houthis that it remains focused on maintaining freedom of navigation in the Red Sea-by force if necessary. Simultaneously, partners need to recalibrate and reinforce their public messaging with strong, clear, united statements that the international community will not tolerate these illegal attacks. And they must be prepared to follow up these statements with action.

Private messaging to Tehran via diplomatic channels could also help dissuade Iranian and Houthi elements from exploiting the gap in coverage. Relatedly, U.S. officials should downgrade additional intelligence about Houthi-Iran coordination on weapons supply and maritime targeting, enabling partners to seed this information into their own public and private messaging.

The uptick in ship attacks is partly attributable to the waning of international support for the coalition in recent weeks. To protect international commerce and hold the Houthis accountable for their illegal acts, Washington will need to reinvigorate the coalition and expand international participation. The carrier gap also comes at a sensitive time in the Gaza war, with Israel's Rafah campaign continuing to make headlines, Prime Minister Binyamin Netanyahu scheduled to visit Washington next month, and tensions hitting new highs on the Lebanon border. To manage that problem set while simultaneously maintaining pressure against the Houthis, Washington will need to demonstrate new levels of commitment and capacity in the region.

Elizabeth Dent recently joined The Washington Institute as a senior fellow after serving as director for the Gulf and Arabian Peninsula in the Office of the Secretary of Defense.