Members of the 31st Marine Expeditionary Unit's Battalion Landing Team take positions while training on Camp Hansen, Okinawa, March 6, 2026. (Ryan M. Breeden/Stars and Stripes)
Sending a Marine expeditionary unit from Okinawa to stand by in the Middle East leaves a gap in U.S. power in the Indo-Pacific while increasing the defense burden on its Asian allies, according to analysts.
The amphibious assault ship USS Tripoli and roughly 2,500 members of the 31st Marine Expeditionary Unit have been en route to the Middle East since March 13, according to multiple news reports. The Tripoli and its amphibious ready group — the amphibious transport docks USS San Diego and USS New Orleans — are homeported at Sasebo Naval Base, Japan.
The III Marine Expeditionary Force and 7th Fleet referred questions about the deployment to the Pentagon, which declined to comment Monday, citing operational security.
Members of the 31st Marine Expeditionary Unit's Battalion Landing Team train on Camp Hansen, Okinawa, March 6, 2026. (Ryan M. Breeden/Stars and Stripes)
The 31ST MEU unit has “unique capabilities” that would not be easily replaced without moving another expeditionary unit into the region, said retired Marine colonel Grant Newsham, a senior researcher with the Japan Forum for Strategic Studies in Tokyo.
“Unfortunately, the U.S. Navy doesn’t have enough amphibious ships in working order to keep enough MEU’s fully operational and deployable these days,” he said by email Wednesday.
The 31st is one of seven Marine expeditionary units and the only one permanently deployed in the Pacific. It features a combination of air, ground and support elements designed to quickly respond to combat and noncombat situations, including humanitarian assistance and evacuations.
Even if additional forces from the I MEF in California were moved into the region, “the lack of amphibious ships is a constraint,” Newsham said.
The 855-foot Tripoli can carry MV-22 Osprey tiltrotors, F-35 fighter jets and a variety of helicopters, such as the MH-60S Seahawk.
Sending the unit out of the Pacific “certainly sends a negative message to U.S. allies and partners about U.S. commitment and focus” on the region, said retired Navy lieutenant Luke Collin, former director for Japan and Australia at the U.S. National Security Council and principal at the Asia Group advisory firm in Washington, D.C.
But pulling U.S. combat ships, aircraft, long-range munitions or integrated air and missile defense systems out of the Pacific “could have more significant impacts on U.S. deterrence,” he said by email Wednesday.
“Although I don’t expect China, Russia, or North Korea to push aggression further in the near-term, they will certainly seek to exploit this situation to press the narrative that the U.S. is a declining and unreliable power in Asia,” Collin wrote.
The outcome of a conflict in the Indo-Pacific may not hinge entirely on the Marines’ absence, said Benjamin Blandin, a research fellow with the Yokosuka Council on Asia Pacific Studies.
“In case of a direct Chinese attack on Japan or Taiwan, both should be able to hold up for at least a few weeks, granting enough time for the [Marine Corps] to come to the rescue,” he said by email Thursday.
Newsham said regional allies in the interim must rely on their own defense capabilities.
“It’s just the reality of the world today and the size of the U.S. military,” he wrote.
Stars and Stripes reporter Alex Wilson contributed to this report.
