Members of the Ground Self-Defense Force and U.S. Army take part in Orient Shield 19, a set of joint exercises that also included the GSDF's Type 12 surface-to-ship missiles and the U.S. Army's high-mobility artillery rocket system. (Video footage by The Asahi Shimbun)

Japanese and U.S. ground forces for the first time staged a simulated attack against an enemy ship using land-to-ship missiles at a training site in Kyushu.

The joint exercise on Sept. 17 at the Oyanohara training area in Kumamoto Prefecture had China in mind as a potential target of future operations.

It was the first joint exercise in Japan between the U.S. Army and the Ground Self-Defense Force involving land-to-ship missiles.

A similar joint exercise was held last year in the United States.

The U.S. side operated the high-mobility artillery rocket system (HIMARS) during the drill, which forms part of Orient Shield 19 joint exercises being held in various locations.

A GSDF unit handled Type 12 surface-to-ship missiles (SSM) in the exercise, with the training area serving as an outlying island under attack from a warship at sea.

China's growing maritime presence in the region was likely a key factor behind the joint exercise, analysts said.

In recent years, Chinese naval ships have repeatedly navigated the waters separating the main Okinawa island from Miyakojima island to the south. Since December 2016, the Chinese aircraft carrier Liaoning and its escort fleet have passed through the waters on three occasions.

In 2018, a Chinese nuclear submarine was spotted in the area.

Chinese government ships have also frequently intruded into Japanese territorial waters around the Senkaku Islands, which Beijing also claims sovereignty over.

Against this background, the GSDF is stepping up efforts to protect southwestern islands off Kyushu by deploying a SSM unit to Amami-Oshima island off southern Kagoshima Prefecture.

GSDF personnel have also been deployed to Miyakojima and Ishigakijima island. The SSM is capable of flying at low altitudes.

Given that this year's joint exercise was held in an area facing China, it is likely designed to highlight the close cooperation between Japan and the United States in defense matters.

(This article was written by Yoshitaka Ito and Nanami Watanabe.)