Department of Justice Official Releases Letter Admitting U.S. Amnesty of Japan’s Unit 731 War Criminals

Jeffrey Kaye
May 14, 2017 · 29 min read

Upon my request, both the Department of Justice (DOJ) and the Simon Wiesenthal Center have released copies of a December 1998 letter from DOJ official Eli Rosenbaum to Rabbi Abraham Cooper of the Simon Wiesenthal Center. In the letter, Rosenbaum admitted to Cooper that after World War II the United States government had classified records pertaining to a Japanese military unit that engaged in biological warfare experimentation and field trials on humans.

The letter, one of two released to this author, confirmed the U.S. “essentially assisted Japan in covering up the atrocities perpetrated by the unit.”

In 1998, Rosenbaum was director of DOJ’s Office of Special Investigations (OSI), while Rabbi Cooper was associate dean of the Wiesenthal Center. The occasion for the correspondence was the Wiesenthal Center’s sponsorship of a “Trans-Pacific Video-Conference on Japanese Wartime Atrocities,” held at the Center’s own Museum of Tolerance on August 16, 1998.[1]

Reported briefly in the press at the time,[2] Rosenbaum’s letter of December 17, 1998 ended any doubts that the U.S. government had given scientists and military personnel associated with the notorious Japanese biological warfare program of the 1930s-1940s “immunity [from prosecution at the International Military Tribunal, Far East] in return for their human experimentation research data.”[3]

This appears to have been the first time that any U.S. government official admitted publicly and officially that the U.S. had proposed an amnesty for the members of Japan’s Unit 731 and assorted components, known to have murdered thousands of prisoners in illegal biological experiments, and hundreds of thousands of soldiers and civilians in biological warfare operations predominantly in China, but also the Soviet Union, from 1939 until nearly the end of World War II.

While Rosenbaum’s letter was quoted in the press, and in a 2002 Congressional Research Service report, the letter itself, and a November 1998 letter to Cooper also on the subject of Japan’s war crimes, were never released publicly. These letters are now available with the publication of this article, along with supporting documentation that until now was also not available.

From letter by Eli Rosenbaum, DOJ, to Abraham Cooper, Wiesenthal Center, Dec. 17, 1998

This article looks at some of the salient issues in regards to aspects of these new documents, including the motivation for the U.S. amnesty action, the question of experimentation on U.S. and allied prisoners of war (and its possible cover-up), and the question of assigning culpability to those involved. The article concludes with remarks on these matters by both Rosenbaum and Cooper, who were interviewed for this article in Spring 2013. (The delay in publishing this information was occasioned by personal matters.)

Unit 731

Beginning with John Powell’s 1980 article, “Japan’s Germ Warfare: The US Coverup of a War Crime,” and a subsequent article in the October 1981 Bulletin of Atomic Scientists, “A Hidden Chapter in History”, revelations concerning long-hidden or suppressed aspects of Japanese war crimes began to surface in the U.S. and Western press. Powell shocked the American public by writing about and producing documentary evidence of a cover-up of “Japan’s use of biological warfare against China and the Soviet Union.”[4]

The primary Japanese military unit associated with the biological warfare research and production of weaponry was known as Unit 731, although there were a number of other military units also involved. Powell (1981) wrote, “The American government’s participation in the cover-up, it is now disclosed, stemmed from Washington’s desire to secure exclusive possession of Japan’s expertise in using germs as lethal weapons.”

The original promise of amnesty for information was made after a discussion some months after the end of World War II between the Ft. Detrick’s Colonel Murray Sanders and General Douglas MacArthur, according to numerous accounts of Unit 731’s history. The finalization of such a deal, however, took a few years, and was not without controversy within government circles.

Powell (1980) quoted a July 1, 1947 memo from two U.S. doctors associated with bacteriological research that Japanese researchers had thousands of slides of human tissues taken from their experiments on prisoners. The slides and reports from the Unit 731 researchers were available if the U.S. could provide assurances the Japanese doctors and scientists would be saved from war crimes prosecution. The two doctors, Edward Wetter and H. I. Stubblefield argued that since “any ‘war crimes’ trial would completely reveal such data to all nations, it is felt that such publicity must be avoided in the interests of defense and national security of the U.S.”

The vagueness of the language — “it is felt” — appears to indicate their message was something discussed comprehensively in their circle, in particular by scientists from the Army’s Ft. Detrick, which was the center of a major crash program in biological warfare research begun during the war, and intelligence officers.[5] Ft. Detrick personnel had been in charge of the debriefing of the Unit 731 doctors and scientists, while various documents speak to the sharing of such information with intelligence agencies.

According to Powell, Wetter and Stubblefield furthermore indicated “the knowledge gained by the Japanese from their experiments ‘will be of great value to the U.S. BW research program’ and added: ‘The value to the U.S. of Japanese BW data is of such importance to national security as to far outweigh the value accruing from war crimes prosecution.’”

The furor over Powell’s revelations peaked in the mid-1980s with public controversies over Japanese biological warfare (BW) experiments on U.S. and allied prisoners of wars. Congressional investigators ignored evidence of such experiments on U.S. POWs. It wasn’t until the publication of Linda Goetz Holmes’s book, Guests of the Emperor: The Secret History of Japan’s Mukden POW Camp (Naval Institute Press, June 2010) that any mainstream historian accepted such experiments even took place. The entire episode is still ignored in the press accounts of World War II history.

Subsequently, the scandal around Unit 731 appeared to die down publicly, until it was revived approximately a decade later. In 1995, there were two major narratives published on Unit 731 and the U.S. immunity deal. One was an article by Nicolas Kristof in the New York Times. The other was historian Sheldon Harris’s book, Factories of Death: Japanese Biological Warfare, 1932–45, and the American Cover-up.[6] The publication and controversy surrounding the publication of Iris Chang’s book, The Rape of Nanking, in November 1997, also brought greater attention to the issue of Japanese atrocities during World War II.

Amnesty to Protect Collaboration and to Protect U.S. Biowar “Expertise”

The supporting documentation for this article includes two memoranda for the record from the early 1980s by Norman Covert, then Chief of Public Affairs and historian for the U.S. Army at Ft. Detrick, Maryland. Rosenbaum’s December 17 letter had quoted liberally from the latter of these two memoranda.[7] While it is worth considering the portions Rosenbaum did not quote, the selection revealed to Rabbi Cooper, taken from Covert’s May 5, 1982 Memorandum for the Record, explained the U.S. rationale for the Unit 731 amnesty:

The Joint Chiefs of Staff decided to keep Top Secret any information about the Japanese Biological Warfare Program. The Joint State, War, Navy Coordinating Committee expressed its desire that the information be retained in US hands exclusively and certainly it should be kept from the Soviet Union….

In the [June 26, 1947] memorandum written by Dr. Edward Wetter and Mr. H. I. Stubblefield[8] for the State, War, Navy Coordinating Committee for the Far East, the decision not to prosecute LTG [Lieutenant General Shiro] Ishii [founder and leader of Unit 731 and the biological warfare program] was discussed. “An agreement with Ishii and his associates that information given by them on the Japanese BW program will be retained in intelligence channels is equivalent to an agreement that this government will not prosecute any of those involved in BW activities in which war crimes were committed.”

…. Scientists in the US program said the information was not of significant value, but it was the first data in which human subjects were described. It indicated the Japanese program reached a level of expertise in 1939 that was never advanced because of lack of resources. Any prosecution of LTG Ishii and his associates would have exposed the Japanese capability in addition to US expertise. It would have been difficult to retain such information in US-only hands in such a case. The Joint Chiefs of Staff and SCAP [Supreme Command Allied Powers] agreed there would be little gained by such prosecution and deferred, offering LTG Ishii immunity in exchange for detailed information. [bold added for emphasis]

The Covert memorandum was certainly a kind of spin, although Mr. Covert himself may not have been aware of the full extent of U.S. crimes. Even so, he admitted to this author in an interview for this article that at the time he wrote the memos he was concerned mainly with “protecting Ft. Detrick[‘s]” reputation. The May 5 memo, and an earlier one Covert wrote on November 17, 1981, were a response to media attention following the Powell disclosures. The November 17 memo was undertaken as a rewrite of the May 5 memo for the purpose of submission to the Secretary of the Army.

“News media was beating me to death on that,” Covert said, referring to the strong response to the Powell articles. “The Memorandum for the Record was to cover your ass, a record of what I had done.”

Covert added there had also been “several legislative requests” for more information on the Unit 731 material as well. He also recalled that the Department of Justice had also contacted him on one occasion during this period, although he did not remember the details. Rosenbaum indicated in his interview that DOJ had likely been involved in some capacity in the postwar discussions surrounding the granting of amnesty to Ishii and associates.

The question of the value of the Japanese data and biological samples is a matter of conjecture, while the controversy over the use of such data (and similar data from the Nazi concentration camp experiments), including use of operational knowledge in purported U.S. germ warfare attacks on North Korea and China during the Korean War, is a separate, though related issue.[9] At one point, Covert said U.S. scientists found the Japanese research “not of significant value.” He appeared to have gotten this information from speaking to Ft. Detrick scientists still resident in the Frederick, Virginia area. In addition, Covert appeared to give little credence to evidence that came from Soviet sources.

But elsewhere, writing about Ft. Detrick representative Dr. Norbert Fell’s interrogation of Shiro Ishii, Covert wrote in his November 17, 1981 memo, “The data on human testing appeared to have significant value to the U.S. BW Research programs at Camp Detrick.” Some months later, in his May 5, 1982 memo, Covert concluded, “It is certain the Japanese had a full-scale BW effort and achieved a level of expertise working with many traditional BW agents.”

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Photograph of Shiri Ishii (masao takezawa / wikimedia commons)

A later report by Doctors Edwin Hill and Joseph Victor, also from Ft. Detrick, was quite direct when considering the value of getting the Unit 731 data. “Such information could not be obtained in our own laboratories because of scruples attached to human experimentation,” they wrote.[10]

To conclude the discussion on the value of Unit 731’s data, it is worth noting a May 1947 memo from MacArthur’s office to the War Department and Major General Alden Wiatt of the Chemical Warfare Service on the BW human experiments, “confirmed tacitly by Ishii” to interrogators. The memo was obtained by author William Triplett, and also describes the intersection of the amnesty agreement with unnamed intelligence agencies:

“Data already obtained from Ishii and his colleagues have proven to be of great value in confirming, supplementing and completing several phases of U.S. research in BW, and may suggest new fields for future research…. For all practical purposes an agreement with Ishii and his associates that information given by them on the Japanese BW program will be retained in intelligence channels is equivalent to an agreement that this Government will not prosecute any of those involved in BW activities in which war crimes were committed.”[11]

MacArthur’s command told the War Department, “valuable technical BW information as to results of human experiments and research in BW for crop destruction probably can be obtained….”

Ft. Detrick’s Norbert Fell resumed interrogations of Shiro Ishii two days after this memo was sent.

The POW Question

Eli Rosenbaum’s long quotation from the May 5 Covert memo did not include all the information that likely is of interest to historians. The Covert memo, which reads like a detailed reply to Powell, addresses Powell’s claims that U.S. and British POWs had themselves been victims of Japanese biological experiments. Powell had noted the brief reference to such experiments during the Khabarovsk war crimes trials of Unit 731 and Unit 100 participants in late 1949.[12]

“There is no information available to support the allegation that US or allied citizens were victims….” Covert wrote. “Reports from the War Crimes Trials conducted in the Soviet Union in 1949 suggest caucasians may have been used, but no other source provides a basis for this determination. “

Yet, in his 1980 article in the Bulletin of Concerned Asian Scholars, Powell had quoted a response to a Wetter and Stubblefield memo by a member of SWNCC (the “[Department of] State, War, Navy Coordinating Committee”), Cecil F. Hubbert. Hubbert told his colleagues “experiments on human beings similar to those conducted by the Ishii group have been condemned as war crimes by the International Military Tribunal [in Nuremberg].” He furthermore warned, “… there is a remote possibility that independent investigation conducted by the Soviets in the Mukden area may have disclosed evidence that American prisoners of war were used for experimental purposes of a BW nature and that they lost their lives as a result of these experiments….”

SWNCC was a joint body formed to coordinate occupation policy and actions in Japan. According to a document found by Doreen Lustig, and noted in passing in her paper on the Nuremberg Nazi Industrialist trials, Cecil Hubbert is identified as “Acting Chief, War Crimes Branch, OSS”,[13] raising the question as to what degree OSS and its later incarnations as the Central Intelligence Group or Central Intelligence Agency were involved in the decisions around the Unit 731 amnesty, or the investigations into experiments done on U.S. POWs. It is worth recalling, as noted above, that the U.S. government was promising that information on the Ishii amnesty and resulting BW data would be kept in “intelligence channels.”

Looking for documentation of the POW experiments, Powell produced a memorandum written to the Director of the FBI in 1956 in which a Mr. James J. Kelleher Jr., reportedly from the Department of Defense’s Office of Special Operations, ‘…volunteered further comments to the effect that American Military Forces after occupying Japan determined that the Japanese actually did experiment with ‘BW’ agents in Manchuria during 1943–44 using American prisoners as test victims.”[14]

But Covert maintained in his May 1982 memo that a “close review” of SCAP intelligence files failed to find “supportive evidence” of such experiments on American or British POWs. But just a few years later, British researchers Peter Williams and David Wallace produced a 1985 documentary in Britain that included interviews with former POWs who described the experiments Japanese doctors had performed on them. Williams and Wallace also published the information in their 1989 book, Unit 731.[15]

For this article, Covert, supplied a copy of a memo concerning a May 1995 Department of Defense [DOD] review of “Q’s & A’s Regarding Unit 731.” The memo, by DOD’s Lisa Bronson, concerned allegations of Japanese biological experiments on U.S. POWs.

Bronson, who appeared concerned with DOD public statements totally denying evidence of Unit 731 medical experiments on POWs, wrote, “… one should be extremely circumspect about broad, sweeping claims concerning the definitive nature of ‘evidence’ and ‘documentation’ in regard to allegations of BW experimentation on US prisoners of war.” While “dispositive documentary evidence” of such experimentation was lacking, Bronson thought “circumstantial evidence, which some could argue is compelling, exists in the form of Soviet interrogations of Japanese prisoners and diaries kept by both American and British POWs present in the camp at Mukden, Manchuria….”

She concluded, “At a minimum, the documentation of these allegations suggests that it may be unwise to make the broad sweeping claim that ‘there does not appear to be any documentary evidence to support clams that US POWs were subjected to biological experimentation.’”

In fact, in recent years, further documentation concerning the activities of Ishii’s Unit 731 at Japan’s POW camp in Mukden, Manchuria, has demonstrated that some prisoners were indeed used in medical experiments. In Linda Goetz Holmes’s book noted above, she presented documentary evidence that the Commander in Chief of the Japanese Kwangtung Army in Manchuria had ordered the Army’s “Anti-Infection and Water Supply Main Depot (Unit 731 at Ping Fan) to dispatch the medical team to the Mukden POW camp” (pg. 17 in Holmes). Colonel Taro Nagayama, the chief of Unit 731’s Section 4, the Medical Examination and Treatment Section, was to head the team.

Holmes also described the Soviet’s questioning of Major Tomio Karasawa at the Khabarovsk trials. Karasawa had been the chief of the biological production section at Unit 731, and confirmed that his department had studied the response of American POWs to infectious diseases. They did this, Karasawa said, “to decide the reaction of an immunizing serum inoculation according to races,”, i.e., per Holmes, “to see if Caucasian Americans reacted to bacterial infections in the same way as Asians” (pg. 30 in Holmes).[16]

It is also worth noting that POWs were apparently also the subjects of medical experiments at other camps, particularly in the Southwest Pacific.[17]

There have been several Congressional hearings into the POW matter, though no conclusive actions have ever been taken. Attempts to bring Japanese companies or the Japanese government to U.S. courts by private individuals seeking damages for harm done as POWs have been unsuccessful.[18]

The Culpability of Ishii

Department of Justice’s Rosenbaum did not quote in his letter to Rabbi Cooper some paragraphs in Covert’s memo concerning the decision not to charge Lt. General Shiro Ishii with war crimes. Today there is ample documentation concerning Ishii’s clear role in leading and organizing the biological experiments and implementing the field operational use of biological weapons during the Sino-Japanese and Japanese-Soviet wars. But no book on the subject had yet been published in English when Covert was writing the memo upon which Rosenbaum based his evidence.

Covert’s May 1982 narrative states that SCAP G-2 (intelligence) investigations on Ishii could produce no more than “hearsay, anonymous letters, rumor and affidavits” from former Japanese soldiers on Ishii’s role in the biological warfare unit’s crimes. One would think the affidavits would count as evidence, but Covert concluded, “SCAP G-2 could not verify the charges.”

Yet Covert also discussed the difficulties of assessing Ishii’s case without bias. “The extreme sensitivity of biological warfare research and development in the United States and the need to protect — in the US interest — any information received posted special problems for SCAP investigators in pursuing War crimes charges,” Covert wrote.

In fact, one of the SCAP affidavits was from Major General Kiyoshi Kawashima, the former Chief Medical Officer of the 1st Army Group of the Kwantung Army, and Chief of the Production Division of Unit 731 under Ishii, who was questioned by the Soviets at Khabarovsk on September 12th, 1946.[19] (Unit 731 and associated units were organized formally under the Kwantung Army, and various Kwantung officers, including Kawashima, and Kwantung Army Commander-in-Chief Yamada Otozoo, were put on trial by the Soviets.)

A separate affidavit came from another Ishii subordinate, Major Tomio Karasawa, a sectional chief also with Unit 731’s production division, whose testimony at Khabarovsk on research on American POWs with infectious diseases was described above.

A document from the International Prosecution Section (IPS) of the International Military Tribunal for the Far East (IMTFE) described the affidavits from Kawashima and Karasawa, in addition to other affidavits “on file with IPS.” While Covert indicated he had queried SCAP documents, he never referred to a search of IPS records, and we know from later investigations by Sheldon Harris and others that IPS had looked fairly deeply into the Unit 731 allegations.

Yet as documents now open for public review at the University of Virginia Law Library War Crimes Trial Collection, available digitally on the Internet,[20] SCAP G-2 kept close tabs on the evidence gathered by IPS investigators. On June 22, 1947, a memo[21] from the War Crimes division of the War Department Special Staff, Civil Affairs Division (WDSCA WC) to Col. Alva Carpenter, chief of SCAP’s legal section, detailed a request for “soonest clarification and further details… particularly IPS opinion as to whether evidence warrants opinion that Japanese BW group headed by Ishii did violate rules of land warfare.”

The author of the unsigned memo told Carpenter that the War Department was “satisfied evidence now in possession” did not warrant the prosecution “of Ishii and his group.”

It is strange that the War Department’s War Crimes office back in Washington D.C. was so sure that evidence was lacking for prosecution.

In their reply five days later, the legal section at MacArthur’s Far East Command described two affidavits from Unit 731 officers that detailed bacteriological experiments on prisoners, as well as the use of biological weapons air campaigns on Chinese cities. The weapons included the deliberate spread of bubonic plague, typhus, typhoid, cholera and anthrax. Carpenter, or whoever wrote the return memo, concluded, “I am of the opinion that foregoing information warrants conclusion that Japanese BW group headed by ISHII did violate rules of land warfare, but this expression of opinion is not a recommendation that group be charged and tried for such” (italics added).

The affidavits in question, from Major General Kiyoshi, former Chief of Unit 731, and Major Karasawa, former Medical Chief of a section of Unit 731, had been given by the Soviets to the Americans.

Yet, while the subject of Unit 731’s crimes surfaced ever so briefly and tantalizingly during the U.S.-led Tokyo War Crimes Trial itself, the prosecution had already decided to forego pursuit of the issue, for much the same reasons Covert had already described. Indeed, as early as December 1946, the Special Assistant to Chief of Counsel at the Trial, Eugene Williams, told his replacement in his office that it was his opinion that evidence regarding bacteriological warfare “was not sufficient to warrant opening that issue,” even though the Soviets had witnesses ready to send from Vladivostok.[22]

For the next few years, there was extensive debate inside the government about whether or how much to collaborate with the Soviets on the question of Ishii and Unit 731. For their part, though upset over the Americans refusal to take up the issue at the Tokyo International Military Tribunal, the Soviets themselves did not raise the issue publicly until they undertook their own separate trial of Kwantung Army and Unit 731 officers, doctors, and technicians in December 1949.[23]

Cooper and Rosenbaum on the Amnesty Controversy

Eli Rosenbaum, who was involved in tracking down Nazi war criminals from Kurt Waldheim to Arthur Rudolph, commented for this article on the cover-up surrounding Japan’s use of biological weapons and medical experiments on prisoners.

“Very little attention was paid to the fact the Emperor of Japan was involved [in the biological warfare program], and left undisturbed,” Rosenbaum said.

Rosenbaum indicated he didn’t know if the U.S. decision to amnesty Ishii was wrong to make at the time. “I don’t have information about that,” he said. “If the goal was to prevent the Soviets from obtaining very, very dangerous information, then that might have been an acceptable choice. But I don’t have that kind of information.”

“These are important issues,” he continued, “because as long as countries are at loggerheads there will be instances where it becomes possible to employ covertly someone from the other nation, and people will have to make these decisions when people have done terrible things. You can be sure very bad people are being employed by intelligence agencies. And we have to hope they [the intelligence agencies] know the ethical issues.”

As an example, Rosenbaum mentioned Operation Paperclip, the U.S. program that brought Nazi scientists to the United States in large numbers.[24]

“I never saw that anyone making the decisions knew there was an ethical issue, or a moral component” to the Paperclip activities, Rosenbaum said in what was a rare statement of criticism by a U.S. government official of the post-World War II policy of letting a number of Nazi war criminals into the United States.

Asked to comment on Rosenbaum’s conditional, national security exception for the concept of granting amnesty to someone like Ishii, Rabbi Cooper replied, “He’s not a scholar in that area. You’re asking him to make a historic and moral call. He’s an official of the U.S. Justice Department. Gen. Ishii’s activities were such that they should have been adjudicated as crimes against humanity or war crimes. This was a guy who was developing WMDs, and look where we are today, worried about WMDs.”

Still, Cooper was loathe to criticize Rosenbaum. “Eli Rosenbaum has devoted most of his life to tracking down Nazi war crimes,” Cooper told me.

Eli Rosenbaum was asked if the US should apologize for the amnesty to Ishii and his associates. He replied:

“I’m not aware of any discussion along those lines.[25] I’ve not heard until now a request of that nature. The first question that needs to be answered about that was was the decision wrong? I don’t have enough information about that. They made that decision. When I discuss these kinds of things, we here in law enforcement routinely let criminals get away with their crimes, if they will testify with someone higher up in the chain…. [Rosenbaum gave the prosecution of John Gotti as an example.] We prosecutors have to do all this in the daylight. As a prosecutor, before we enter into an agreement with that we have to think about how this will play in the daylight of public opinion. On the intelligence side, they don’t have — what did Jefferson call it? — the antiseptic of sunlight. You have to rely on the people who do it, who have all the available facts.”

Japan Continuing to Block Access to Information

According to newspaper articles in the late 1990s, the U.S. Department of Justice tried for years to get information from the Japanese government about the Unit 731 war criminals, as there was a policy of not allowing such war criminals into the United States. But the Japanese government refused to comply with U.S. requests, making it the “only country in the world” that has failed to provide such assistance.[26]

“We wanted access to their archives, as we’ve had access elsewhere, Germany, etc., “ Rosenbaum said in the interview for this article, “but we’ve never been granted access to this day.”

Asked if the Department of Justice had continued to ask Japan for the information, the former director of DOJ’s Office of Special Investigations said, “I don’t know when was the last request for access. There comes a point when it’s quite clear the cooperation will not be extended to you.”

In a separate interview for this article in April 2013, Rabbi Abraham Cooper was asked if he stood by the statements he made years earlier criticizing the U.S. amnesty of Unit 731 personnel.[27]

“I absolutely — I feel that way today even more. The potential of abuse in the field of medical and scientific research, the potential is even greater. The threat of WMD is even greater. The potential has been democratized. It’s a terrible stain.

“We all know the Russians, Americans, the Brits, if they could have gotten Ishii and kept him, they would have. But symbolically, to make the statement the amnesty was wrong would be a good thing.”

Rabbi Cooper was especially critical of the current Japanese government:

“The main culprit — there’s plenty of blame to go around, including the United States — has been Japan. Japan because of Hiroshima and Nagasaki quickly grabbed the cloak of victimhood. Young Japanese don’t know why the atomic bomb was dropped. If they had done as the Germans, with lots of books, documentaries, films, give the context for a discussion and debate. There is a profound implanted revisionism in Japan. Second reason, to quote Mr. [Simon] Wiesenthal, I heard in 1980 lectures on college campuses. Someday the cold war will be over, and people will ask who won, the East or the West. And I’ll tell you who won. The ex-Nazis won. Because they were able to leverage the Cold War to assure they were never going to be dealt with in a systematic way.”

Rabbi Cooper referred to the fact that the medical personnel who were amnestied went on to staff major positions in Japan’s postwar medical establishment. The Unit 731 issue was “unresolved because Japan’s medical and ethical practices were put into the hands of these people after WWII,” Cooper said.

“Unit 731 should not only be a place in China where people come from all over the world to see how horrible the Japanese were, but should be a warning to all mankind of what can happen when knowledge and science are misused.”

[Update, September 23, 2019: It has come to my attention that Eli Rosenbaum’s letter to Abraham Cooper was quoted in a December 2002 Congressional Research Service (CRS) report to Congress. The report was titled “U.S. Prisoners of War and Civilian American Citizens Captured and Interned by Japan in World War II: The Issue of Compensation by Japan.” [28]

In the report, CRS Information Research Specialist Gary K. Reynolds quoted Rosenbaum that two then-recently declassified reports had “confirm[ed] that Ishii and his colleagues received immunity from prosecution and that, in exchange, they provided a great deal of information to U.S. authorities.”

Reynolds indicated that a copy of Rosenbaum’s 1998 letter had been faxed to him. But the letter itself was not then released. Instead, it took 15 more years for the incriminating letter to be released to the public.]

[1] China News Daily, Aug. 14, 1998, CNET reported on the conference at the time: URL See also the original announcement of the event by the Simon Wiesenthal Center, archived online at (all accessed May 14, 2017).

[2] See Stars & Stripes, week of March 15–28, 1999, vol. 122, no. 6, reposted online at (accessed May 14, 2017).

Reference was also made in a Congressional Research Service report by Gary K. Reynolds in December 2002, “U.S. Prisoners of War and Civilian American Citizens Captured and Interned by Japan in World War II: the Issue of Compensation by Japan,” online at (accessed May 14, 2017).

[3] Letter, Eli Rosenbaum to Abraham Cooper, December 17, 1998.

[4] Powell’s 1980 article was published in the Bulletin of Concerned Asian Scholars, “Japan’s Germ Warfare: The US Coverup of a War Crime” (Oct.-Dec. 1980, vol. 12, no. 4.) See URL: (accessed May 14, 2017).

Powell’s 1981 article is available online, reproduced as part of the Congressional Record on November 10, 1999, (accessed May 14, 2017) Powell died in Dec. 2008.

In the middle 1970s, John Saar at the Washington Post wrote a story, “Japan Accused of WW II Germ Deaths” (Nov. 19, 1976), that described a Japanese documentary by Haruko Yoshinaga, aired by the Tokyo Broadcasting System on Unit 731. “Japanese scientists killed at least 3,000 Chinese prisoners in World War II in bacteriological warfare experiments and escaped prosecution by sharing the findings with US occupation forces…. Press officers at the US Defense and Justice Departments said they had no information on the charges but would investigate,” Saar wrote. (See URL:,6138361 — accessed May 14, 2017) But no one in the Western press pursued the story further until Powell published his first article four years later.

The impact of Powell’s expose can be gauged by the fact that 60 Minutes interviewed Powell for an on-air segment, “War Crime,” on April 4, 1982. The transcript for this episode is available beginning on pg. 352 in this large PDF file online: URL

Morley Safer narrated: “During World War II, the Japanese military experimented with germ warfare. Their guinea pigs were Chinese, Russian and American prisoners of war. For a variety of reasons, the American government kept it all a secret.”

[5] The U.S. World War II program in both chemical and biological warfare is discussed in Robert Harris and Jeremy Paxman, A Higher Form of Killing: The Secret History of Chemical and Biological Warfare, Random House, 2002.

[6] Nicolas D. Kristof, “Unmasking Horror — A special report. Japan Confronting Gruesome War Atrocity,” New York Times, March 17, 1995, URL: (accessed May 14, 2017).

Routledge published an expanded, revised version of Factories of Death in 2002. Harris died a few months later.

[7] My thanks to Mr. Norman Covert for sharing certain documents. The attempt to obtain the documents through official channels is a story in itself. A DoD spokesman had referred my query to Fort Detrick. Ft. Detrick’s FOIA office referred me to the National Archives. But the documents did not apparently exist there either. They may or may not constitute documents that Mr. Covert claims were destroyed by order of Ft. Detrick’s commanding officer in 1998.

[8] “Mr. H. I. Stubblefield” was in fact Dr. Henry I. Stubblefield, a bacteriologist who we know, at least in 1954, was on the Chemical Corps Advisory Council, according to an in-house history of Ft. Detrick written by Norman Covert. See URL: Coincidentally, along with two other researchers, he had co-authored with Andrew C. Ivy an article in 1934, “Protective Action of Sodium Thiocyanate against Dysentery Toxin (Shiga): An Experimental Study in Dogs and Rabbits.” Ivy was later to be a major figure testifying on medical ethics at the Nuremberg trials.

According to Powell (1980), Dr. Wetter was at the time of the SWNCC memo “Panel Director” of the “Committee on Biological Warfare.” Powell does not say, but it appears likely this was the secret “DEF” committee, the third of three secret committees formed during the World War II years by the National Academy of Sciences and National Research Council. See URL: (accessed May 14, 2017). Wetter later went to work as a civilian employee for the Office of the Assistant Secretary of Defense for Research and Development ( According to the 1955 Official Register of the United States, p. 114, Wetter worked in this office as “Executive Secretary, Committee and Panel on Special Operations.”

[9] See Till Bärnighausen, “Data generated in Japan’s biowarfare experiments on human victims in China, 1932–1945, and the ethics of using them,” Japan’s Wartime Medical Atrocities: Comparative Inquiries in Science, History, and Ethics, Taylor and Francis, 2010.

On the Korean War allegations, see Stephen Endicott & Edward Hagerman, The United States and Biological Warfare: Secrets from the Early Cold War and Korea, Indiana University Press, 1998.

[10] Op. cit., Bärnighausen, p. 97.

[11] See William Triplett, Flowering of the Bamboo, Woodbine House, 1985, pp. 241–250.

[12] Until recently, the transcripts from the USSR’s war crimes trial of Unit 731 personnel at Khabarovsk, USSR in late 1949 were long out of print. But in 2016, Google Books published a free e-book of the original Soviet publication. See Materials on the Trial of Former Servicemen of the Japanese Army Charged With Manufacturing Bacteriological Weapons [Testimony and Exhibits from the Khabarovsk War Crimes Trial], Foreign Languages Publishing House, Moscow, 1950, published as free e-book at Google Books, URL: [accessed May 14, 2017]

[13] Doreen Lustig, “The Nature of the Nazi State and the Question of International Criminal Responsibility of Corporate Officials at Nuremberg: Franz Neumann’s Behemoth at the Industrialist Trials,” June 20, 2011, Institute of International Law and Justice, Working Paper 2011/2, History and Theory of International Law Series, NYU School of Law. URL: (accessed May 14, 2017).

[14] The memo quoting Kelleher is also published along with this article.

[15] The Television South documentary made headlines in both Britain and the U.S. See “British PoWs tell how they were germ lab ‘guinea pigs,’” London Times, August 12, 1985; and “Japan did germ war tests on POWs, says TV show,” Associated Press, in Wisconsin Milwaukee-Sentinel, August 12, 1985. On December 5, 1985, Hugh Downs at ABC’s show 20/20 did a video segment called “Alliance of Shame” that examined the charges of POW experimentation by Unit 731.

[16] It is worth noting that Holmes also found that the International Committee of the Red Cross sent a representative to the Mukden POW camp and reported a “rosy picture” of camp conditions, and that there were three ICRC visits overall. That these visits never reported any signs of experiments on prisoners, and even praised the medical aid given to POWs there, adds some piquancy to China and North Korea’s refusal to have the ICRC investigate the use of germ warfare by allied powers during the Korean War. See chapter nine, “Red Cross Double-crossed,” in Linda Goetz Holmes, Guests of the Emperor: The Secret History of Japan’s Mukden POW Camp, Naval Institute Press, 2010

[17] See Holmes, 2010; and Yuki Tanaka, Hidden Horrors: Japanese War Crimes in World War II, Westview Press, 1996.

[18] On the Congressional hearings, see Jack Anderson and Dale Van Atta, “Did Japanese Mistreat U.S. POWs?”, Lawrence Journal World, Oct. 4, 1987, p. 3. URL:,523650 (accessed May 14, 2017).

See also Reynolds’ CRS report (2002), which also discusses the legal aspects of the private lawsuits by POW survivors.

In addition, a book by a supporter of the POW claimants to reparations from Japan, Lysle Lewis’s Search for Truth: Japan’s Experiments on POWs (unpublished, 1988), is available online. It appears to have been the product of a prodigious amount of research. See link at bottom of this webpage: (accessed May 14, 2017).

[19] Part of Kawashima’s testimony can be read online at the University of Virginia Law School Digital Library (UVLL), which has posted a number of Unit 731 documents. For Kawashima, see (accessed May 14, 2017).

The proceedings of the Khabarovsk war crimes trial were published in English by the Soviets. See Materials on the Trial of Former Servicemen of the Japanese Army Charged with Manufacturing and Employing Bacteriological Weapons, Foreign Languages Publishing House, Moscow, 1950. The book has been published free online via Google Books. URL:

[20] “The Personal Papers of Frank S. Tavenner, Jr. and Official Records from the IMTFE [International Military Tribunal for the Far East], 1945–1948,” The Tokyo War Crimes Trial Digital Collection, (accessed May 14, 2017)

[21] UVLL URL: Part of the Frank Tavenner collection at the University of Virginia (assessed May 14, 2017).

[22] Letter, Eugene D. Williams to Frank S. Tavenner, Jr., Dec. 4, 1946. URL: (accessed May 14, 2017).

[23] For an extensive discussion of the issues surrounding US and Soviet conflict surrounding the biological warfare and experimentation war crimes charges, see Harris, 2002; and also Peter Williams and David Wallace, Unit 731: The Japanese Army Secret of Secrets, 1989, Hodder and Stoughton, London; and Daniel Barenblatt, A Plague Upon Humanity: the Secret Genocide of Axis Japan’s Germ Warfare, 2004, Harper, New York. (Barenblatt’s book was reissued in 2005 with a slightly different title: A Plague Upon Humanity: The Hidden History of Japan’s Biological Warfare Program.)

[24] For information on Project Paperclip and associated programs, see Linda Hunt, Secret Agenda: The United States Government, Nazi Scientists, and Project Paperclip, 1945 to 1990, St. Martin’s Press, 1991; Tom Bower, The Paperclip Conspiracy: The Hunt for the Nazi Scientists, Little, Brown and Company, 1987; Paul Julian Weindling, Nazi Medicine and the Nuremberg Trials: From Medical War Crimes to Informed Consent, Palgrave Macmillan, 2004; and Annie Jacobson, Operation Paperclip: The Secret Intelligence Program that Brought Nazi Scientists to America, Little, Brown and Company, 2014.

Bower’s book describes how Dr. Kurt Blome, who was acquitted at the Nuremberg doctors’ trial, later went to work for the Americans, though he was not accepted into the Paperclip program. Blome was a former SA general and Director of the Central Institute for Cancer Research. He was also one of the Nazis’ primary biological warfare experts.

According to Jacobson, who has the most extensive account of Blome among any of these authors, Blome, who was interrogated for months at the Allies’ “Dustbin” interrogation center at Castle Kransberg, by summer 1946 was working as a doctor at the U.S. Army Military Intelligence Service Center at Darmstadt.

According to Weindling, Nazi scientific administrator and the head of the planning bureau and head of the planning bureau for the Reichsforschungsrat, Werner Osenberg, told U.S. interrogators after the war that Blome was one of the Nazi’s “leading figures” in biological warfare work. Despite Blome’s placement as head of biological warfare research, he was acquitted of war crimes at the Nuremberg Doctors’ Trial.

Bower further described Blome’s work with the Americans: “Blome was interviewed about his work by Dr. H. W. Batchelor and three other American biological experts from Camp Detrick, Maryland” (p. 255). He subsequently went to work for the Americans at the Army’s European Command Intelligence Center in Oberursel, Germany.

Blome’s biological warfare research is discussed at some length in Ute Deichmann, Biologists Under Hitler, Harvard University Press, 1996. I asked Cooper if the Wiesenthal Institute had ever investigated the Blome case. The rabbi said he wasn’t sure but he believed Wiesenthal was looking into it at the time of his death.

Testimony in regards to Blome’s leading role in the Nazis’ biological research work, and the Nazi program in general, was given on August 26, 1946 by Major General Walter Schreiber at the Nuremberg trial of Class A war criminals. URL:

Interestingly, it was only three days later, on August 29, that David Sutton raised the issue of “poison” experiments on prisoners at the Japan International Military Tribunal, something Sutton indicated, upon a judge’s questioning, the U.S. was not going to pursue at trial.

[25] After the interview with Eli Rosenbaum, I subsequently became aware of an article by Jing-Bao Nie in the December 1, 2002 edition of The Lancet (Volume 360, Pages s5 — s6), “Japanese doctors’ experimentation in wartime China.”

Nie told readers, “To monopolise the data from the inhuman experiments and to develop their own biological warfare programmes, US officials offered Japanese doctors immunity from prosecution in exchange for their data. This deal was made at the same time as they brought the Nazi doctors to trial. As a result, in the Tokyo trial in 1946, the International Military Tribunal Far East, led by the USA, deliberately concealed the crimes of the Japanese doctors. This treatment of Japanese doctors by the USA can never be justified by the standards of moral traditions in any culture. Any government that supports and exploits such atrocities should apologise and compensate.”

[26] Teresa Watanabe, “Japan Blocking Probe of War Criminals, U.S. Says,” L.A. Times, Dec. 9, 1998. URL:

See also Ralph Blumenthal and Judith Miller, “Japan Rebuffs Requests for Information About Its Germ-Warfare Atrocities,” New York Times, March 4, 1999. URL: (accessed May 14, 2017). In this article Rabbi Cooper is quoted as saying, on March 4, 1999, a New York Times article quoted Cooper as saying bluntly, “This blanket amnesty can’t stand.’’

[27] In an April 26, 1999 op-ed for the L.A. Times, Rabbi Cooper wrote: “Washington should also immediately rescind the blanket amnesty granted to these criminals. But Japan must also awake from its self-inflicted amnesia.” See URLs: and (accessed May 14, 2017)

[28] See Gary K. Reynolds, “U.S. Prisoners of War and Civilian American Citizens Captured and Interned by Japan in World War II: The Issue of Compensation by Japan,” December 17, 2002, Congressional Research Service, The Library of Congress. URL: (accessed September 23, 2019).

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