In the early hours of Nov. 1, 2020, the silence is broken by the sound of an amphibious assault featuring Japan Self-Defense Force CH-47JA Chinooks touching down and delivering streams of Amphibious Rapid Deployment Brigade troops while U.S. Marines hit the beach via small boats briskly navigating over the horizon from the USS Ashland to Gaja-Jima. As they disappear in fast-moving columns into the foliage of the small uninhabited island off the coast of Japan, their counterparts to the south are already preparing missile launchers and coordinating fire support against enemy targets on land and sea.

These scenes and more dotted the islands and waters off the coast of Japan for the past two weeks, as U.S. Marines and the JSDF conducted Keen Sword 21, a bilateral exercise with a series of wide-ranging missions focused on strengthening the interoperability of forces forged through the 60-year-old alliance.

ARDB members took point alongside Marines with 1st Battalion, 3d Marine Regiment arriving from the air and sea in a bilateral amphibious assault on Gaja-Jima featuring troops from both forces landing simultaneously on the remote island and demonstrating the ability to eliminate an occupying enemy.

“Working with the Japanese forces, I could tell they are masters of their trade. Setting up bilateral security upon insertion and relaying information across units came with ease,” said Cpl. Juan Pena, a team leader with 1st Bn., 3d Marines.

This mission showcased a combined ability to seize territory threatened by an adversary, defend key maritime terrain, and establish expeditionary advanced bases for follow-on operations through swift, integrated, and lethal action.

“Our interaction with the ARDB was seamless as if we previously trained with that specific unit,” said Sgt. Ashton Wilson, a squad leader with 1st Bn., 3d Marines. “I would not hesitate to serve with them in combat or other operations.”

More than 200 miles to the south, a complex but effective integrated joint targeting and fire support coordination effort maintained a blistering pace, with elements of the U.S. Army’s 17th Field Artillery Brigade joining 12th Marine Regiment and 3d Marine Division in mobile command-and-control nodes on Camp Hansen and Camp Courtney in Okinawa.
Employing deliberate and dynamic targeting against land, sea, and air targets, these Marines and Soldiers further enabled the bilateral amphibious force to maneuver through the littorals while supporting naval operations at sea.

One such precision, long-range fires capability was on display as High Mobility Artillery Rockets System launchers, from both the Marine Corps and Army, landed on beaches via ocean-going transports in support of an amphibious raid elsewhere in the exercise area. HIMARS launchers can be moved throughout a distributed maritime environment via air, sea, or land. This freedom of movement, coupled with the long-range strike capability of HIMARS, means that the U.S.-Japan team can rapidly move precision-fire weapons into position and strike distant targets smoothly.
Meanwhile, Marines from the 5th Air-Naval Gunfire Liaison Company integrated into the ARDB and embarked on a Japan Maritime Self-Defense Force ship to enhance combined command and control capabilities to further enable bilateral amphibious operations.

“Our Marines assisted in mission coordination between the JSDF Amphibious Task Force and USS Ashland with 1st Bn., 3d Marines embarked,” said Maj. Bradley Ebach, air officer with 5th ANGLICO. “During the execution of the bilateral amphibious exercise, we employed a Joint Terminal Attack Controller to assist with close air support and provided liaisons to the ARDB Fire Support Coordination Center during the assault.”

While U.S. and Japan naval and expeditionary forces continued operations at sea and establishing advanced bases, Marines with 1st Bn., 2d Marines and 1st Bn., 3d Marines conducted a grueling force-on-force exercise stretching across the challenging terrain of the jungles in northern Okinawa. As the Marines battled through the heat and humidity and thick vegetation in the hilly jungles, members of 1st Bn., 2d Marines and the JSDF’s 15th Brigade exercised command and control through combined operations centers located on Camp Foster and Marine Corps Air Station Futenma.

“This force-on-force evolution in a jungle environment provided a realistic training opportunity focused on defeating a peer adversary in any climb and place,” said Maj. Dennis Graziosi, who brings combat experience from Afghanistan to his current assignment as operations officer for 1st Bn., 2d Marines. “Integrating these operations with joint and bilateral command and control nodes at other location on Okinawa increases our interoperability with allies and bolsters our ability to fight together.”

Keen Sword 21, the latest in a series of regularly-held exercises between Japan and the United States, represents continuing advancements among the longtime allies in combined operations across an increasingly distributed and complex environment. Through this exercise, the shape of future operations in the region is on display – fast, fluid, and together with allies and partners.