The port is near the Spratly Islands, where China continues to build up reefs into artificial islands. Japan plans in fiscal 2016 to send ships to Cam Ranh for the first time, letting them refuel and restock on food and other supplies. Defense Minister Gen Nakatani will likely sign an agreement on the matter with Vietnamese counterpart Phung Quang Thanh during a Nov. 6 meeting in Hanoi.

Building up defenses

China's claims on territory within its "nine-dash line" in the South China Sea have put the country in conflict with Vietnam, the Philippines and others. Vietnam is moving to station submarines at a base in Cam Ranh, which Nakatani is set to visit -- a clear symbol of Japan and Vietnam's cooperation on naval security.

SDF ships have already called at ports in Ho Chi Minh City, Da Nang and elsewhere, though those locations are more distant from disputed regions in the South China Sea. Letting Japanese ships refuel and re-provision at Cam Ranh would greatly expand the potential range of SDF activities in the area, which lies over 2,000km from the Japanese mainland. That distance, combined with a dearth of refueling opportunities, has so far made surveillance and other operations a logistical challenge.

The port call is designed to counter Chinese militarization of the area. Boosting the Japanese presence at Cam Ranh will "help deter Chinese military activity in the South China Sea," a government official said.

Japan and the U.S. also look to tighten military cooperation in the region. The U.S. on Tuesday began sailing a warship within 12 nautical miles of China's man-made islands -- area China claims as a territorial sea. The deployments are intended to assert freedom of navigation in the area. China has so far responded with repeated warnings and by tracking the ships.

The SDF and U.S. Navy will shortly begin joint exercises north of the island of Borneo to ensure smooth communication, troop transfers between ships and other core maneuvers. The exercises will involve vessels including a U.S. aircraft carrier and a Japanese escort vessel that has participated in joint India-U.S.-Japan drills. Two Japanese escort ships involved in anti-piracy efforts off of Somalia in the Gulf of Aden will also pass through the South China Sea starting in November, surveilling the area as they do so.

Cautious start

Yet Japan remains cautious of provoking China. Tokyo does not at this time plan to use the Cam Ranh port for meaningful surveillance and warning operations. Vessels calling at the port will likely be limited to those engaging in anti-piracy efforts and training.

It is unknown to what extent Vietnam, the U.S. and others will be able to hold off Chinese military development in the South China Sea. Even if patrol efforts in the waters surrounding China's islands continue, "there's nothing we can do to stop construction of runways, radar facilities and other structures on the islands themselves," a Defense Ministry official said. Many fear that further Chinese militarization of the area could greatly expand the country's capacity for surveillance and other operations.

Nikkei Asian Review - October 30, 2015