Brig. Gen. Trevor Hall, commander of the 3rd Marine Expeditionary Brigade, poses with Maj. Gen. Hajime Kitajima, commander of Japan's Amphibious Rapid Deployment Brigade, during the Iron Fist opening ceremony at Camp Hansen, Okinawa, Feb. 19, 2025. (Keishi Koja/Stars and Stripes)

CAMP HANSEN, Okinawa — U.S. and Japanese troops on Wednesday kicked off an exercise aimed at strengthening island defense and amphibious capabilities amid regional security concerns.

Iron Fist, which runs through March 7, comes as Japan faces “the most severe security environment it has seen since the end of World War II,” Maj. Gen. Hajime Kitajima said during the opening ceremony at Camp Hansen.

“No one can deny the possibility that a crisis like the invasion of Ukraine may occur anywhere in the world,” he told a formation of 240 U.S. Marines, sailors and Japanese soldiers. “We need to strengthen our deterrence and response capabilities now more than ever. Strengthening island defense capabilities is one of the most urgent issues.”

China has increased military activity near Taiwan, which it claims as its own, and spent a record 355 days in 2023 patrolling waters near the Senkaku Islands, administered by Japan but also claimed by China and Taiwan.

Brig. Gen. Trevor Hall, commander of the 3rd Marine Expeditionary Brigade,speaks alongside Maj. Gen. Hajime Kitajima, commander of Japan's Amphibious Rapid Deployment Brigade, during the Iron Fist opening ceremony at Camp Hansen, Okinawa, Feb. 19, 2025. (Keishi Koja/Stars and Stripes)

Iron Fist focuses on expeditionary advanced base operations and cross-domain operations, key concepts of the Marine Corps’ Force Design restructuring plan, according to Brig. Gen. Trevor Hall, commander of the 3rd Marine Expeditionary Brigade and deputy commander of III Marine Expeditionary Force.

“The combined field training that we’ll conduct during this exercise will clearly demonstrate our ability to operate together,” he told the troops. “It will further enhance our capabilities to rapidly deploy and respond across the range of military operations throughout the region.”

The drills are taking place at multiple locations, including Camp Hansen, Kin Blue Beach Training Area, Camp Courtney, the Northern Training Area, Ie Shima Auxiliary Airfield and Japan’s Camp Naha. Additional training is scheduled at Vice-Camp Takayubaru and Camp Ainoura on Kyushu and Okinoerabu Island, 43 miles northeast of Okinawa.

An amphibious operation at Kin Blue Beach on March 1 will serve as the “key bilateral training event” of the exercise, according to 31st Marine Expeditionary Unit spokesman Maj. Edward Pingel.

U.S. Marines and Japanese soldiers display their flags during the Iron Fist opening ceremony at Camp Hansen, Okinawa, Feb. 19, 2025. (Brian McElhiney/Stars and Stripes)

Now in its 19th year, Iron Fist focuses on “combined planning to improve preparedness through real-world amphibious training,” Pingel wrote in an email Wednesday. The exercise includes advanced marksmanship, amphibious reconnaissance, fire and maneuver assaults, bilateral logistics, medical support and fire support operations such as mortars, artillery and close-air support.

Approximately 2,700 U.S. Marines and sailors and 1,300 Japanese troops are expected to participate. Military observers from England, France, Germany, the Netherlands, Australia and the Philippines are also attending.

French army chief of staff Gen. Pierre Schill and German army chief Lt. Gen. Alfons Mais are expected to meet with U.S. and Japanese commanders, including III MEF commander Lt. Gen. Roger Turner and Japan Ground Self-Defense Force chief of staff Gen. Yasunori Morishita, Morishita said at a Feb. 13 news conference.