Japan's Ground Self-Defense Force and the U.S. Marine Corps on Wednesday disclosed to the press some detail about an ongoing joint exercise in which the defense of remote islands is being drilled.
As China becomes increasingly assertive in regional waters, the GSDF's Amphibious Rapid Deployment Brigade and the Okinawa-based U.S. 31st Marine Expeditionary Unit have been conducting drills over three weeks since March 4 at a GSDF facility in central Japan.
During the disclosed portion of the exercises, an F-35 stealth fighter jet belonging to the U.S. Marine Corps for the first time participated in an exercise with the GSDF.
The drills assume the training site in Shizuoka Prefecture is an island held by enemy forces and Wednesday's programs included the Japanese amphibious brigade passing on information to the Marines to help the fighter jet locate and engage targets.
The participation of the F-35, which did not actually open fire, is a sign that the bilateral security alliance has deepened since Japan's new security laws took effect in 2016.
The laws enable Japan, under certain conditions, to exercise the right to collective self-defense or defend allies even when the country is not directly attacked.
"We are committed to our enduring foundation and to building interoperability," Col. Masashi Hiraki, commander of the Japanese unit, said at the training area near Mt. Fuji.