The international media has been gripped by the "standoff" between Washington and Tokyo over the Okinawa base issue, although we suspect a deal will be worked out and commitments made by both governments during previous administrations will, as they should, be honored with at best only minor adjustments.

But lurking behind the scenes is another sensitive issue which could just as easily put the alliance at risk if not properly handled; Japanese Prime Minister Yukio Hatoyama's apparent determination to unveil details of an alleged "secret pact" between Japan and the United States — one that is said to allow U.S. vessels and aircraft carrying nuclear weapons to stop in Japan. This investigation threatens a collision between Tokyo's three non-nuclear principles and the U.S.-Japan alliance relationship that serves as the cornerstone of the U.S. commitment to Japan's defense.

While we applaud transparency in government, the Democratic Party of Japan government needs to be fully aware of the potential consequences of this investigation if followed through to its logical conclusion.

In December 1967, then-Prime Minister Eisaku Sato introduced the "three non-nuclear principles," which pledged that Japan would not possess, manufacture or allow the introduction of nuclear weapons into Japan. That policy — it was passed as a parliamentary resolution in 1971 and is not a law — reflected Japan's deep-rooted aversion to nuclear weapons and helped Sato win the Nobel Peace Prize in 1974. It has been a pillar of Japanese diplomacy and foreign policy ever since — Hatoyama renewed Japan's "firm commitment" to these principles in a speech to the United Nations Security Council just last month.

That pledge notwithstanding, for decades there have been rumors of a secret "don't ask, don't tell" arrangement between Japan and the U.S. that allowed the U.S. to keep nuclear weapons on ships and aircraft that stopped in Japan or transited its waters. Previous Japanese governments denied this deal existed, and it became moot in 1991 when then-President George H.W. Bush ordered the removal of all tactical nuclear weapons from deployed U.S. ships and aircraft.

Nonetheless — and here's the rub — the U.S. still follows a strict "neither confirm nor deny" policy in discussing the presence of U.S. nuclear weapons anywhere to avoid precedents that could limit its flexibility, threaten operational security during periods of crisis or conflict or compromise nuclear storage facilities on U.S. territory.

As part of its "transparent government campaign," the DPJ pledged that it would uncover the truth behind the allegations if it won the August parliamentary elections. After taking office, Foreign Minister Katsuya Okada said his office would launch an inquiry and "we will reveal everything we find."

Fine. Then what? Let's say that the Hatoyama government comes up with "proof" that such a deal existed. What happens next?

Is the Hatoyama government then prepared to announce "case closed" and move on, or will it feel compelled to take measures to ensure this could never happen again — a move that would force Washington to choose between maintaining its "neither confirm nor deny" policy or maintaining the alliance? That might seem like a simple choice to the Japanese but it is not so easy for Washington, which has to always keep one eye on precedents and how this would affect operations and alliances elsewhere.

Facing a similar choice when an anti-nuclear government came to power in New Zealand in 1984, the U.S. chose to let go of its long-standing ANZUS alliance and continue bilaterally with Australia alone. Auckland further complicated the issue by also banning nuclear-powered ships, but it was the "neither confirm nor deny" straw that broke that camel's back. New Zealand remains outside of ANZUS to this day.

Before the Hatoyama government paints itself into a corner, it needs to think through where it plans to go with its "secret pact" investigation and make clear to the Japanese people — and its U.S. allies — what the desired end result will be. Is Tokyo really prepared to open this pandora's box merely to score political points over a "history" issue? Or is the DPJ playing a high-stakes game of chicken, assuming the U.S. will "blink" and continue to defend Japan despite clear indications that U.S. security requires it to maintain opacity when it comes to transporting its nuclear weapons? Neither move makes sense.

It is hard to see a way out of this cul-de-sac unless the Hatoyama government spells out in advance how far it plans to take its investigation and to what end.


Ralph A. Cossa is president and Brad Glosserman is executive director of the Pacific Forum CSIS, a Honolulu-based nonprofit research institute affiliated with the Center for Strategic and International Studies in Washington. They wrote this commentary for The Advertiser.