The military integration between Japan and the U.S. is insidiously afoot in Okinawa.

Our Maritime Self-Defense Force and the U.S. Navy have reportedly installed the latest model of the Sound Surveillance System (SOSUS), which extends over the Pacific side of the Nansei Islands, at the Okinawa Ocean Observatory of the U.S. White Beach Naval Facility in Uruma, and they are jointly involved in its operation.

Classified as the biggest of secrets sanctioned under the Japan-U.S. security framework, this joint operation is only known to the prime minister, the defense minister, and other select high-level officials. No deliberation was held in the Diet, and no explanation was offered to either Urawa or Okinawa. In a Sept. 10 press conference, Katsutoshi Kawano, Chief of Staff of the Joint Staff Council, declined to comment on the system. The whole operation is still shrouded in the veil of "secrecy."

This can be interpreted as an effort to curb China's maritime muscle-flexing. But at the same time, this kind of proactive surveillance might unnecessarily escalate tensions with China. And if something goes awry, if history is any guide, it is Okinawa that will have to bear the biggest brunt.

The SOSUS spreads its cables across the sea bottom, and with its sonar system collects data, such as sound waves and magnetic data, coming from submarines, to monitor their movements. The cables, extending to the south of Kyushu and Taiwanese waters, each measure a few kilometers.

The gathered data belongs to both Japan and the U.S. So if a skirmish were to flare up in the Taiwan Strait, that data might be used for America's military operations. Apparently, collective self-defense is already in action, when it is still merely a bill.

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Speaking of U.S.-Japan military cooperation, just last month, an American military chopper crashed off the coast of Uruma.

At the time, 10 Japanese soldiers were taking part in an operational exercise with a U.S. special army unit on an American battleship. But we wouldn't even be talking about this now if two of them hadn't been injured. In fact, this exercise was not a one-time thing, but had been going on for five years. They say it's just "training," but I'd say it's more of a "joint drill."

Since 2007, the Self-Defense Forces' use of the U.S. Camp Hansen has been on the rise; it's a new normal now. Moreover, we now know that in 2012, the Ministry of Defense was considering 13 U.S. military facilities and two nearby bodies of water for "joint use."

Last December, according to the minutes of his talks with the U.S. top brass, Kawano had stated his desire to jointly use Camps Hansen and Schwab.

Japan and the U.S. are insidiously getting ever more interlocked.

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During the Cold War, in order to monitor USSR submarines, Japan and the U.S. installed the old SOSUS in Tsugaru and Tsushima Straits. We now have the new SOSUS in Okinawa, as well as at the Shimokita Ocean Observatory in Aomori. This is definitely to curb China's ever-increasing truculence.

Yet, the security bill currently under debate is woefully opaque as to intelligence sharing and joint military operations with the U.S. The government should first clear that up.