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Digital Archive International History Declassified

July 10, 1969


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    Ambassador Shimoda cautions that Japan's signing of the NPT still "requires further consideration from a long-term perspective."
    "Cable No. 2124, Ambassador Shimoda to the Minister for Foreign Affairs, 'Issues concerning the Signing of the Nuclear Non-Proliferation Treaty (Opinion Statement)," July 10, 1969, History and Public Policy Program Digital Archive, Diplomatic Archives of the Ministry of Foreign Affairs of Japan, File No. 2011-0741. Contributed by Yoko Iwama and Yu Takeda and translated by Ju Hyung Kim.
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July 10, 21:15 – Sent from the United States

July 11, 10:55 – Received at MOFA

To: Minister for Foreign Affairs

From: Ambassador to the United States Shimoda

Subject: Issues concerning the Signing of the Nuclear Non-Proliferation Treaty

(Opinion Statement)

No. 2124 Top Secret

Recently, it seems that there is a discussion in Japan that Japan should sign the NPT since it joined the committee on disarmament [Eighteen Nation Committee on Disarmament (ENCD)]. It goes on to say that it is appropriate to sign the NPT when the minister or the Prime Minister visits the United States this fall. Regarding this matter, the following is my opinion for your reference.

1. The NPT was originally a product of the U.S.-Soviet cooperation under the previous Johnson administration. The new Nixon administration appears to be less enthusiastic for this treaty than the previous administration. It reportedly explained to Chancellor Kiesinger during the recent presidential visit to [West] Germany that the U.S. government hopes Germany to sign the Treaty but would by no means put pressure on the issue. As for Japan, it have to admit that there was a significant difference in how Secretary Rogers handled the issue during the minister’s recent visit to the United States (the Secretary himself made no reference to this matter and the ACDA Director Smith attended the beginning of the second session briefly to touch upon this matter) in comparison to the attitude of former Secretary Rusk trying to persuade former foreign minister Miki to sign the treaty.

Considering the attitude of the new administration, it could be said that we do not necessarily need to rush to sign the treaty in light of the overall relationship with the United States or the Okinawa issue. In addition, though the United States might ask us to promptly sign the Treaty in the future, we will have no problem by replying that our stance on this Treaty requires more cautious consideration because of China’s nuclear weapons development and the Soviet Union’s non-determination of its stance on this Treaty.

2. Japan’s accession to the ENDC does not justify Japan’s early signing of the NPT. On the contrary, it showed significant diplomatic pressure to the countries concerned and strengthening Japanese bargaining position, both of which were caused by the fact that a country having advanced economic and technical nuclear development capabilities, such as Japan, has maintained cautious attitude toward signing the NPT. If Japan had been a signatory to this treaty from the beginning as the United States and the Soviet Union have asked, both countries would not have pushed forward Japan’s accession to the ENDC in such a forceful manner. In this regard, Mexico and other countries had a point in criticizing the arbitrary U.S.-Soviet chairmanship. Besides the United States, there is a significant difference in the power to speak up in international society from the perspective of the Soviet Union. It was rather a big concession to the Soviet Union to admit to single out Japan and Outer Mongolia to join the ENDC as representatives of the free world and the communist world, respectively.

3. From the outset, a true intention of Soviet Union is probably a demand for Japan to sign the NPT in exchange for the approval of Japan’s membership in the ENDC, and for Germany to sign the NPT in a same way. In any case, while the circumstances of this case show how much value the Soviet Union attaches to Japan’s NPT signature, it is doubtful whether the Soviet Union will continue to attach the same importance to Japan’s voice once Japan signs the Treaty. It is considered to be no longer a problem of signature of the NPT but should be fully examined from the perspective of overall relations with the Soviet Union. In particular, it appears to be the point that should be considered in dealing with the problem of the Northern Territories after settling down the Okinawa problem.

4. Some Japanese opponents against NPT signature focused on Japan’s freedom of action that should be reserved to proceed with nuclear armament in the future. I do not agree with such a view, and conversely, believed that it is necessary to reserve freedom of action for a while in order to make current nuclear weapons states to proceed with genuine nuclear disarmament.

In other words, looking to the future, the Soviet Union will never ratify the NPT until Germany signs and ratifies it. In the meantime, though the United States and the Soviet Union should proceed with missile negotiations, their agreement would freeze the status quo of their nuclear forces at best, even if they are successful. It is not expected to be genuine nuclear disarmament.

The United States and the Soviet Union are believed to started to work together to create an NPT as they were motivated by (a) a self-benefiting desire to advance their status in international politics by fixing the exclusive status of possessing nuclear weapons, and (b) fear of seeing the emergence of a nuclear chaos in the event that a large number of countries possess nuclear weapons as the technical advancement of non-nuclear weapons states are condoned. If Japan, Germany, and other potential nuclear weapons states sign the NPT, fear of (b) will be resolved and only the purpose of (a) can be achieved. Under such circumstances, the expectation that the nuclear weapons states will pursue nuclear disarmament by throwing off their advantageous position on their own is too naive.

5. On the contrary, if Japan and Germany remain outside the framework of the NPT and the current international situation remains unchanged, while the economic position and international status of both countries will be improved year by year, some nuclear weapons states will likely suffer from the burden of maintenance and development of nuclear weapons.  Their economic condition will deteriorate, and even social unrest would be intensified. If this trend continues, it is natural that there will be a time when Japan and Germany are able to use their enormous economic power and potential nuclear capabilities as weapons to carry out epic diplomacy that will pave the way for the abolition of nuclear weapons by letting nuclear weapons states to determine nuclear disarmament. In any case, the signing of this Treaty is a matter that requires further consideration from a long-term perspective, as Japan’s freedom of action will be compromised for a long period of 25 years if it signs the NPT. In particular, it is thought that Japan should cooperate and act in a cautious manner with Germany that is in the same position as ours.

Transferred to [Japanese diplomatic missions in] Geneva, the United Nations, [West] Germany, and the Soviet Union.



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