Nuclear Noh Drama
Tokyo, Washington and the Case of the Missing Nuclear Agreements

President Richard M. Nixon and Japanese Prime Minister Eisaku Sato meeting at the Western White House in San Clemente, California in January 1972. Nixon and Sato worked out the final details of the Okinawa reversion agreement during these meetings.

[Source: Collection RN-WHPO: White House Photo Office Collection (Nixon Administration), 01/20/1969 - 08/09/1974; Richard Nixon Library - College Park, College Park, MD]

Posted - October 13, 2009

Edited by Dr. Robert A. Wampler

Washington, D.C., October 13, 2009 - The election of the new Democratic Party government in Japan led by Yukio Hatoyama raises a significant challenge for the Obama administration: the status of secret agreements on nuclear weapons that Tokyo and Washington negotiated in 1960 and 1969.  For years, the  ruling Liberal Democratic Party claimed that there were no such  agreements, denying, for example, allegations that they had allowed U.S. nuclear-armed ships to sail into Japanese ports.  Nevertheless, declassified U.S. government documents, interviews with former U.S. Ambassador Edwin O. Reischauer, and memoirs by Japanese diplomats confirm the existence of the secret understandings.  The basic facts about the agreements have been the subject of long-standing controversy in Japan, where a post-Hiroshima anti-nuclear tradition was at odds with secret understandings crafted to support the operational requirements of America's Cold War nuclear deterrent. The Liberal Democrats might have faced a political disaster if they had acknowledged, as appears to be the case, that the U.S. Navy's nuclear-armed ships had free access to Japanese waters.
Seeking to settle the matter, the new Democratic Party government has launched an internal investigation into the agreements and their negotiating history. To aid this investigation, the National Security Archive today posted on the Web the most important U.S. declassified documents on the issue. Nevertheless, Japan is not likely to act unilaterally to declassify the 1960 and 1969 nuclear agreements. The Obama administration should not only assist Japan so that early declassification of the agreements is possible, but also declassify the remaining still-secret U.S. documents, allowing an old controversy can be settled.

The two secret agreements were negotiated during the Cold War, when the United States Navy routinely transited Pacific waters with nuclear weapons onboard and the possibility of a U.S.-Soviet nuclear war was a matter of routine military planning. One of the agreements was actually a record of discussion that established an agreed and carefully defined interpretation of U.S. commitments regarding nuclear weapons, negotiated in 1960, that allowed transit of nuclear weapons through Japanese territory and waters, relegating the consultation requirement to the introduction and basing of nuclear weapons in Japan. The other was part of the 1969 agreement reverting Okinawa to Japan:  U.S. nuclear weapons on Okinawa would be withdrawn but re-introduction would be possible in an emergency.  Even after the end of the Cold War, which brought the worldwide withdrawal of all U.S. theater nuclear weapons, the U.S. government deferred to the Liberal Democrats on the need to keep the agreements secret, but that need is clearly now moot. Declassification is possible and necessary because determining what Tokyo and Washington actually negotiated is a question of significant historical importance and a key missing piece in the nuclear history of the Cold War.


Nuclear Noh Drama
Tokyo, Washington and the Case of the Missing Nuclear Agreements

For nearly four decades, the government of Japan, under the seemingly perpetual control of the Liberal Democratic Party, has repeated a well-rehearsed litany of denials in response to queries from the Diet or the press about alleged secret understandings with the United States regarding nuclear weapons. No, there are no such secret understandings. No, in line with former Prime Minister Eisaku Sato's Three Non-Nuclear Principles, the Japanese government has not allowed the introduction of U.S. nuclear weapons into Japanese territory or waters. The U.S. government has added its own denials, following the long-established "neither confirm nor deny" (NCND) policy with regard to the location of nuclear weapons, as well as repeatedly stressing that the U.S. has always acted in accordance with its treaty obligations to Japan.

However, the new Japanese government of Yuko Hatoyama, which took office in September after an historic election that placed his Democratic Party in power, is moving to bring to light these and other secret agreements between Tokyo and Washington entered into during the height of the Cold War. These include:

  • A secret understanding reached when the Japan-U.S. Security Treaty was revised in 1960 allowing stopovers in Japanese territory by U.S. military aircraft and vessels carrying nuclear weapons
  • A second secret codicil to the 1960 Treaty allowing the U.S. to launch military operations with its forces based in Japan in response to renewed hostilities on the Korean peninsula
  • A secret agreement reached between President Richard M. Nixon and Prime Minister Sato in November 1969 as part of the negotiations for Okinawa's reversion to Japan in 1972 that would allow the U.S. military to bring nuclear weapons into Japan in emergency situations
  • Arrangements for financial payments by the Japanese government to the U.S. to be used for the restoration of sites vacated by American forces as part of the Okinawa reversion agreement. (Note 1)

The new Japanese Foreign Minister, Katsuya Okada, has instructed ministry officials to examine documents on these secret understandings and agreements, a significant effort given reports that the ministry archives hold nearly 2,700 volumes of material relating to negotiation of the 1960 Mutual Security Treaty and about 570 volumes dealing with Okinawa reversion.

Of these agreements and understandings, the most explosive are those concerning nuclear weapons. As noted, the LDP party has long denied the existence of these arrangements, using language agreed upon with the United States to respond to inquiries in the Diet or by the Japanese press. The LDP made these denials in the face of clear evidence in the declassified record that the nuclear agreements in fact exist, though it is more accurate to speak of an understanding or interpretation of treaty requirements rather than a formal agreement with respect to the transit arrangement. Documents detailing both the transit understanding and the issue of nuclear weapons in the Okinawa reversion talks were highlighted in an NHK documentary prepared with assistance from the Archive that aired in 1997 to commemorate the 25th anniversary of reversion. (Note 2)  In addition, the memoirs of former Prime Minister Eisaku Sato's secret emissary to the Nixon administration, Kei Wakaizumi, discussed in detail the secret agreement reached on emergency re-introduction of nuclear weapons into Okinawa after reversion. Wakaizumi's extraordinary account reproduces the actual English-language draft of the agreed minute between Nixon and Sato. (Note 3)

The new Japanese government is to be commended for moving forward to bring these secret understandings to light. Political concerns over the reactions of the Japanese public to revelations that the Japanese government had long turned a blind eye to violations of Sato's Three Non-Nuclear Principles (which the new government has itself vowed to adhere to) combined with U.S. insistence on keeping the understandings secret produced a long litany of official denials by the Japanese government. The Hatoyama government has indicated that it will seek U.S. assistance and cooperation in locating and releasing these agreements. It is very unclear how much help they will receive, however, based on the response that Assistant Secretary of State for East Asian and Pacific Affairs Kurt Campbell made to a question on this matter during a recent press conference:

"Well, first of all, this is a domestic matter at this juncture for Japan. The United States, through the Freedom of Information Act and a variety of historical documents, has laid out a pretty clear picture of what transpired in U.S.-Japan relations during the 1940s, 19 – in early 1950s, 1960s as they relate to nuclear weapons. And so the historical record really speaks for itself, and I think it's part of a diplomacy that took place during the Cold War between Washington and Tokyo.. . . .We would simply say that we'll have little to add to that historical record, and it is up to the Japanese Government how they want to explore this." (Note 4)

Unfortunately, it ain't necessarily so. While a number of documents, which are being posted today, do clearly reference these understandings and agreements, the actual documents have not yet been released. When the Foreign Relations of the United States volume on Japan for 1958-1960 was published in 1994, the editors felt compelled to include a disclaimer that the volume did not provide a comprehensive and accurate record of the negotiations of the U.S.-Japan Treaty of Mutual Cooperation and Security in1960. (Note 5) Among the documents denied release were the Record of Discussion Prepared by the Embassy in Japan, dated January 6, 1960, as well as the exchange of notes on the consultation formula agreed to under the new treaty. (Note 6) Similarly, while a number of the documents available below provide strong evidence for the secret nuclear agreement that was part of the Okinawa reversion arrangements, the documents discussed and reproduced by Prof. Wakaizumi in his memoirs have also not been located or released by the State Department or the Nixon Presidential Library. (Note 7)

Given this state of affairs, the State Department and the White House needs to take advantage of this opportunity offered by the new Japanese government to make public these understandings and agreements that are truly historic in nature, as they reflect the political and strategic framework of the U.S.-Japan security relationship during the Cold War. It was only in 1991 when the George H. W. Bush administration decided to withdraw all theater and tactical nuclear weapons from the field and from ships that events overtook the transit arrangements. In the past, the decision to keep these arrangements secret seems to have been dictated primarily by the need to meet Japanese political sensitivities, a need that is clearly now moot. Release of these documents can also shed light on what appear to be differing historical memories of what was and was not agreed to between Tokyo and Washington as part of the 1960 Security Treaty, especially with respect to the understandings regarding transit vs. introduction of nuclear weapons. As the documents below clearly indicate, the U.S. government during the Cold War firmly believed that the secret interpretation of the consultation requirements under the 1960 Security Treaty provided ample scope for transit of nuclear weapons through Japanese territory and waters, providing the U.S. military with the requisite flexibility to utilize forces in Japan and its nuclear deterrent in the Pacific in the event of war. Whether the Japanese government shared this understanding is a question of significant historical importance and a key issue in the nuclear history of the Cold War. (Note 8)

[Note: The Author would like to acknowledge the assistance of William Burr of the National Security Archive and Daniel Sneider at Stanford University for their assistance with this EBB.]


Document 1 and Document 2: Description of Consultation Arrangements Under the Treaty of Mutual Cooperation and Security with Japan ; and Summary of Unpublished Agreements Reached in Connection with the Treaty of Mutual Cooperation and Security with Japan  [part of briefing book prepared for Secretary of State Herter] ca. June 1960. (From The United States and Japan, 1960-1972, National Security Archive)

These two documents, which were prepared for Secretary of State Christian Herter to use in testifying before Congress on the 1960 Security Treaty, lay out the essential terms of the agreements reached on consultation with respect to the U.S. military forces based in Japan. The first establishes that the introduction of nuclear weapons into Japan, or the constructions of bases in Japan for nuclear weapons and related arms, such as intermediate and long-range missiles, does require consultation with the Japanese government. This document also discusses the secret prior consultation and agreement on the use of U.S. forces based in Japan to meet a military emergency in Korea. The second document summarizes the confidential "interpretation" (the term agreement is crossed out) that the U.S. believes both sides have agreed to with respect to these consultation requirements. With respect to nuclear weapons, consultation is expressly restricted to the "introduction" of nuclear weapons into Japan, a term which, as other document below reveal, is understood as distinct from the transit of nuclear weapons through Japanese territory or waters.

Document 3: Department of State Cable, Tokyo 2335, April 4, 1963, reporting on meeting between Ambassador Reischauer and Foreign Minister Masayoshi Ohira to discuss presence of nuclear weapons on U.S. ships. (From The United States and Japan, 1960-1972)

This cable provides a detailed account of Ambassador Edwin O. Reischauer's meeting with Japanese Foreign Minister Ohira in April 1963, at which Reischauer briefed Ohira on the agreed interpretation of the consultation requirements regarding nuclear weapons, and in particular on the need for precision in the language used to address this issue in public. Finding that Ohira did not have a Japanese language copy of the January 6, 1960 record of discussion that embodied this agreed interpretation, Reischauer used the English-language version to walk Ohira through the understanding, stressing the need to couch the U.S. requirement for consultation in terms of the introduction (‘mochikomu") of nuclear weapons, meaning placing or installing nuclear weapons on Japanese territory. Reischauer also reviewed the U.S. policy of neither confirming or denying the presence of nuclear weapons, and Ohira noted that introduction thus understood did not apply to the "hypothetical" question of nuclear weapons on U.S. naval vessels traveling through Japanese waters.
Document 4: Memorandum, Davis to The Vice President, et al., Subject: NSSM 5 – Japan Policy, April 28, 1969  (From The United States and Japan, 1960-1972)

This National Security Council study, prepared in the spring of 1969, analyzed all the key diplomatic, security and economic issues surrounding U.S.-Japan relations as the Nixon administration took office. One critical issue was negotiation of the reversion of Okinawa to Japan, the focus of Part III of the study which is reproduced here, which raised a number of pressing concerns for the Pentagon, given the significant U.S. military presence on the island, and its strategic importance as a staging area for military operations, including nuclear, in the event of war. Two optional policy boals regarding nuclear storage on Okinawa were either securing the rights to reintroduce nuclear weapons in an emergency, or obtain the rights for nuclear arms ships and aircraft in transit or entering for weather or humanitarian reasons. The detailed discussion of the nuclear issue in NSSM 5 acknowledged that attempting to maintain the status quo regarding nuclear storage and free use of the island for nuclear operations, or some type of interim arrangement under which nuclear weapons would be kept on the island until some future date both presented serious political problems for the Japanese government. This left the options of an agreement on emergency re-introduction of nuclear weapons and/or exercising the flexibility secured by extending the transit agreement from naval vessels to aircraft transiting the island. Based on the Wakaizumi memoir, some combination of the last two options was the basis of the secret agreement between Nixon and Sato in November 1969.

Document 5: NSDM 13: Policy Toward Japan, May 28, 1969 (From The United States and Japan, 1960-1972)

This National Security Decision Memorandum, based on the studies carried out in NSSM 5, laid down the U.S. policy objectives with respect to Japan. With respect to the negotiations on Okinawa, the U.S. goals were an agreement that addressed the U.S. "desire to retain nuclear weapons on Okinawa, but indicating that the President is prepared to consider, at the final stages of negotiation, the withdrawal of the weapons while retaining emergency storage and transit rights, if other elements of the Okinawan agreement are satisfactory." Again, this mirrors what Prof. Wakaizumi described as the agreement reached.

Document 6: Memorandum, Winthrop Brown to U. Alexis Johnson, October 28, 1969, Subject: Okinawa – Preparations for Sato Visit (From The United States and Japan, 1960-1972)

This memorandum, prepared shortly before the Nixon-Sato meetings in November, 1969, echoes NSSM 5 and NSDM 13 in outlining the U.S. objectives with respect to nuclear weapons and Okinawa. To this end, a draft secret agreement on emergency re-introduction of nuclear weapons was being prepared for President Nixon's use in the talks with Sato, though it was still uncertain whether the Japanese Prime Minister would agree to this. With respect to the nuclear transit understanding, Brown notes that "both sides have proceeded on the tacit assumption that transit was permissible. We have to decide whether to let this sleeping dog lie as is or try to cover transit rights specifically."

Document 7: Telecon, Henry Kissinger and "Y" [Kei Wakaizumi], November 15 and 19, 1969. [Source: Document provided by Professor Takashi Shinobu, Nihon University, Japan]

These two memoranda of telephone conversations between National Security Advisor Henry A. Kissinger and "Y," who was later revealed to be Professor Kei Wakaizumi, discuss in somewhat cryptic terms the preparations for the meeting between President Nixon and Prime Minister Sato, including the discussions on the proposed secret agreement regarding nuclear weapons and Okinawa. While the memorandum refers to Item 1, 2, etc., handwritten notes (on the last page of the document) reveal that Item 1 refers to the nuclear issue. The carefully choreographed exchange of draft agreements discussed in the November 15th telecom closely mirrors the account in Professor Wakaizumi's memoirs of the side meeting between Nixon and Sato at which they worked out the final details on the secret agreement for emergency re-introduction of nuclear weapons into Okinawa.

Document 8 and Document 9:  Letter, Acting Secretary of State U. Alexis Johnson to Secretary of Defense Melvin Laird, May 26, 1972; and  Letter, Secretary of Defense Laird to Secretary of State William P. Rogers, June 17, 1972, discussing homeporting of U.S. aircraft carriers in Japan and the nuclear issue (From The United States and Japan, 1960-1972)

These two documents underscore the critical importance the U.S. military assigned to the nuclear transit agreement, and how far they were willing to stretch the notion of transit to ensure operational flexibility for U.S. nuclear forces in the Pacific. The issue was joined as the result of the U.S. Navy wanting to begin homeporting a number of its aircraft carriers in Pacific ports, including Yokosuka in Japan. For Johnson and the State Department, this would incur grave risks, the greatest involving "the question of prior consultation under the Mutual Security Treaty, especially regarding nuclear weapons." Johnson's review of the background to this issue is particularly illuminating. "As you know, we have long felt it in our interest to avoid formal prior consultation under the treaty and the Japanese Government, anxious to avoid responsibility for our actions, has agreed." But in light of the negotiations over prior consultation in connection with the reversion of Okinawa and concern in Japan over U.S. military operations in Vietnam, Johnson feared that regardless of the U.S. position on consultation, the Japanese government would be forced by public debate over the homeporting issue to seek prior consultation and the U.S. would be hard pressed to refuse.

Continuing, Johnson admits that "The Japanese Government, the opposition parties, and the media all believe or suspect that our attack carriers have nuclear weapons on board, and we believe even those who support our present arrangements on nuclear weapons would make a distinction between periodic port visits and a homeporting arrangement as well as between nuclear weapons designed to defend a ship against attack and those used offensively. In any event, public inquiry would center on whether the carrier had nuclear weapons on board and whether the Japanese Government had violated its own policy of not permitting the introduction of nuclear weapons into Japan." Such a debate could put at risk military cooperation between the U.S. and Japan, including the movement of nuclear-armed forces under the transit understanding.

Secretary of Defense Laird, in his response to this letter, methodically addresses and dismisses the concerns outlined by Johnson. Laird agrees the U.S. needs to avoid framing this as a matter for consultation, and argues that in fact it is not such an issue, as the Pentagon does not view the homeporting decision as a major change in the deployment of U.S. forces. On the nuclear issue, Laird was equally direct:

"Concerning the matter of nuclear weapons, I believe that responsible and thinking Japanese, both within and outside of the government, accept the probability that at least some of our ships may carry nuclear weapons, but that it is not in their best interest to belabor the issue with the one ally that is underwriting their security. Under the Nixon Doctrine, one of our major responsibilities is to provide a nuclear shield and credible deterrent posture in the Far East. Japan certainly realizes its need for our nuclear umbrella, as well as our necessity to provide nuclear equipped and trained forces to maintain it."

Laird goes on to reject the option of homeporting the carriers without nuclear weapons as detrimental to the U.S. nuclear deterrent and setting a bad precedent. Finally, with respect to the transit issue, Laird is equally blunt:

"….the record of our negotiations with the Japanese Government . . . is quite clear. When Ambassador Reischauer discussed the subject with Foreign Minister in April 1963 [see Document No. 3 above], Ohira confirmed the Ambassador's understanding that the prior consultation clause does not apply to the case of nuclear weapons on board vessels in Japanese waters or ports. No Japanese Government since then has challenged this interpretation."

Document 10:  Briefing Memorandum, Winston Lord (Policy Planning Staff) to Deputy Secretary of State Ingersoll, et al, January 19, 1972, Subject: Japan's Foreign Policy Trends (with attached paper, same subject) (From The United States and Japan, 1960-1972)

This document is interesting for its evaluation of the transit agreement as both essential as well as a potential cause of serious problems within the U.S.-Japan alliance. Marked NODIS because of its discussion of the transit agreement, the analysis notes that as a subject of public and political discussion in Japan, the transit understanding was currently dormant. However, the Japanese government, through its replies to questions in the Diet, had removed practically all of the remaining ambiguity surrounding the question of whether prior consultation was required if nuclear-armed U.S. naval vessels enter Japanese ports. While there were no signs that Tokyo planned to ask Washington if U.S. vessels were nuclear armed, or might seek prior consultation for U.S. ship visits, the Japanese government had made it clear that they would deny any requests for transit of ships carrying nuclear weapons. If by accident or otherwise it should become public knowledge that a U.S. naval vessel carrying nuclear weapons had entered Japanese waters, the political costs would be very heavy on both sides. Summing up, the paper warned that the nuclear transit question was "potentially the most disruptive issue in our bilateral relations."

Document 11: State Department Cable, Tokyo 09023 to Washington, May 18, 1981, Subject: Reischauer Interview Which Appeared in the Mainichi on May 18, 1981. [Source, U.S.-Japan Relations, 1977-1992]

Finally, this interview between former Ambassador Reischauer and the Mainichi Shimbun provides a clear and unambiguous account of how Reischauer understood the transit agreement, his 1963 meeting with Foreign Minister Ohira and the possible roots of the persistent misunderstandings and differences of interpretation that surrounded the U.S. interpretation of the prior consultation clauses in the 1960 treaty and its understanding of the transit arrangement.



1. See "Skeletons in the closet: Foreign Ministry launches probes into secret dealings with U.S.", Mainichi Shimbun, September 18, 2009, available at  Further information on this subject can be found in at article in the Mainichi Shimbun in an article published on September 18, 2009, the English translation for which was kindly provided me by Daniel Sneider.

2. See Revelations In Newly Released Documents About U.S. Nuclear Weapons And Okinawa Fuel Nhk Documentary, May 14, 1997, available at

3. Kei Wakaizumi, Tasaku nakarishi o shinzamuto hossu [There a were no other options], Tokyo: Bungeishunju, 1994. The English translation of Wakaizumi's memoirs unfortunately does not include these documents, but the copy of the draft understanding reproduced in his memoirs can be found here:

4. Korean Bilateral Meeting and Preview of the Japan Bilateral and Japan-Australia Trilateral Meetings at 2 p.m., Waldorf-Astoria Hotel, New York, NY, September 21, 2009, available at

5. Foreign Relations of the United States, 1958-1960, Volume XVIII, Japan; Korea (United States Government Printing Office, 1994), pp. vii-viii.

6. Ibid; Document no. 130: Editorial Note, p. 258; and Document no. 131: Record of Discussion Prepared by the Embassy in Japan, January 6, 1960, p. 259. As seen in Document no. 3, this is the official U.S. record of the agreed secret interpretations of the consultation requirements under the new treaty.

7. It is also possible that copies of the Nixon-Sato agreed secret minute may be found in the personal papers of former Secretary of State Henry Kissinger, held by the Library of Congress, but these are closed until 5 years after Kissinger's death.

8. On this important issue, see the recent Asahi Shimbun article based on interviews with former Foreign Ministry officials who spoke about the differing understandings of the consultation requirements; Masaru Honda,  "Secret nuclear deal originated from different interpretations of "prior consultation system"; U.S. understanding was that consultation was not required for port calls and passage;" Asahi Shimbun, September 21, 2009; English translation provided by Daniel Sneider.