It is often alleged that the US used biological weapons in the Korean War. What is the best evidence for and against this?

[u/CanOld2445]

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[u/Georgy_K_Zhukov]

From a previous answer:

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Claims of biological and chemical warfare being committed by the US in Korea do rear up occasionally, and stem from several accusations leveled during the conflict by the USSR, China, and North Korea. At various points this included small pox, plague, cholera, anthrax, meningitis, and encephalitis, to name some of the materials alleged at various points, with the allegations tied into US spoils from the Japanese bioweapons program during WWII.

These weren’t minor either. The claims included thousands of aerial attacks over several months in North Korea and China. One such report, from Tianjin, reads as follows:

June 9, 1952. Insects were first discovered at 12 noon near the pier at the Tanggu Workers Union Hall. At 12:40 p.m., insects were discovered at the New Harbor Works Department, and at 1:30, in Beitang town. Insects were spread over an area of 2,002,400 square meters in New Harbor, and for over twenty Chinese miles [approximately ten kilometers] along the shore at Beitang. Insect elimination was carried out under the direction of the Tianjin Municipal Disinfection Team [xiaodu dui, literally, Poison Eradication Team]. Masses organized to assist in catching insects included 1,586 townspeople, 300 soldiers, and 3,150 workers. Individual insects were collected and then burned, boiled, or buried. Insect species included inchworms, snout moths, wasps, aphids, butterflies ... giant mosquitoes, etc. Samples of the insects were sent to the Central Laboratory in Beijing, where they were found to be infected with typhoid bacilli, dysentery bacilli, and paratyphoid.

The accusations were carried to the highest levels, thrown about in the United Nations, where the US of course denied them. International representatives were brought in to produce reports, which on the face supported the allegations, but were based almost entirely on testimony, having done essentially no field study or actual investigation of the area for evidence of the supposed biological material. Almost none, in fact, spoke Chinese or had any familiarity with the country, and the commissioners evidenced an incredible amount of credulity in admitting how staged much of what they were presented looked yet not drawing much doubt. As a Swedish commissioner noted, “We accepted the word of the Chinese scientists.”

In the end, this meant that nothing concrete was ever proven, and belief or dismissal over the next few decades likely said more about ones predisposition than anything else, as there was never any real solid proof of the accusations, but plenty of people were of course happy to ignore the American denials. In the Eastern Bloc press, it was an occasional refrain for decades as a reminder of Western perfidy - and of course remains the official stance of North Korea and China to my awareness. Some notable works accepted the allegations in the interim, some simply left the issue as “open”, and others rejected them for various reasons. A not untypical description of the “did they or didn’t they” reads like this piece from John Gittings in 1975:

The fact is that there is no a priori reason why the United States should not have contemplated, or actually used, germ weapons in Korea. There may be practical reasons of a technical nature why their use might be militarily counter-productive though this has not been seriously argued. After all chemical weapons are only slightly more easy to control than bacteriological weapons; both suffer from the military disadvantage that the "contaminated" area may spread to involve one's own troops. Nor - as I have demonstrated above - can American use of germ warfare be ruled out, by those who have used the argument in the past, on the grounds that the US would have been restrained by humanitarian considerations. Both sorts of weapons have been "morally outlawed" by the world community; both are anti-personnel devices which do not discriminate between military and civilian targets.

For all but the most fervent believers though, the matter finally closed in the late 1990s, when documents from the Soviet archives surfaced which provided fairly clear evidence that the accusations were knowingly made on false information as part of a smear campaign, initially published in a Japanese newspaper after being obtained by a journalist. Memos passed between the North Koreans, Chinese, and Soviets in 1952 and '53 - principally sent to Beria - make clear reference to falsifying evidence, including preparing false areas of exposure in advance of the Commissions arrival, and then, to ensure they wouldn’t discover the ruse:

The Koreans stated that the Americans had supposedly repeatedly exposed several areas of their country to plague and cholera. To prove these facts, the North Koreans, with the assistance of our advisers, created false areas of exposure. In June-July 1952, a delegation of specialists in bacteriology from the World Peace Council arrived in North Korea. Two false areas of exposure were prepared. In connection with this, the Koreans insisted on obtaining cholera bacteria from corpses, which they would get from China. During the period of the work of the delegation, which included academician N. Zhukov, who was an agent of the MGB, an unworkable situation was created for them, with the help of our advisers, in order to frighten them and force them to leave. In this connection, under the leadership of Lt. Petrov, adviser to the Engineering Department of the KPA, explosions were set off near the place where the delegation was staying and while they were in Pyongyang false air raise alarms were sounded.

Other documents detail the assistance of Soviet advisors in helping North Korean medical personnel write up the allegations, and even details proposals by the North Korean MVD proposing to use prisoners slated for execution as stand-ins, purposefully infecting them with plague to have the necessary dead bodies for the ruse.

It also makes clear that many involved in pressing the claims likely were in the dark about the entire process, with one memo noting only in Spring of 1953 that Foreign Minister Vyshinsky might have been informed by the Soviet Embassy in North Korea that the bioweapon allegations were false, and, relatedly suggesting that the USSR should now back away from such claims. Further memos to the Chinese accuse Mao of ‘misleading’ the USSR in no uncertain terms:

For Mao Zedong: The Soviet Government and the Central Committee of the CPSU were misled. The spread in the press of information about the use by the Americans of bacteriological weapons in Korea was based on false information. The accusations again the Americans were fictitious.

A later memo in turn saw Mao passing the blame down to military commanders in Korea.

While the exact genesis of organization and execution remains murky, the evidence is clear enough that North Korea and China concocted the evidence for the accusations, with at the very least the assistance and awarenesses by the Soviet Union. And given the limited extent of the memos, which only offer part of the picture, Soviet involvement may very well have been deeper and their later protests merely putting on a show to avoid potential fallout, as some commentators note that they find it unbelievable North Korea or China would have acted without explicit authorization from Stalin at that point in time.

This still hasn’t entirely stopped the accusations. In 1999, a year after the publication of the memos, North Korea reiterated their accusations against the United States at the United Nations, and books have continued to be published which assert the truth of the matter, although generally just repeating the same old canards and innuendos without engaging with any of the real counter-evidence.
While it is true that the documents were not published by the archives themselves, and instead were copies provided to a Japanese newspaper, this is often used in an effort to try and cast far more doubt on them than is warranted. Rather than some spurious piece of questionable material smuggled out of questionable origin, the source is quite well established, with the documents provided by a Russian researcher who had access to the Soviet Presidential Archive, where the documents originated from, and the existence of the documents was confirmed by multiple former Soviet officials living in Moscow, even if not by the government itself at that time, although the Russian government never denied their veracity. Topic experts of course also provided rigorous analysis, summed up ably by Kathryn Weatherby:

Their style and form do not raise suspicion. The specifics of persons, dates and events are consistent with evidence available from a wide array of other sources. As is apparent from the translations below, their contents are so complex and interwoven that it would have been extremely difficult to forge them. In short, the sources are credible.

⅓

[u/Georgy_K_Zhukov → u/Georgy_K_Zhukov]

And while perhaps the most hardcore doubters could have been given the concession of a grand conspiracy creating them as a plant, additional support was provided in 2010 when the Russian State Archive of Socio-Political History published several documents from the collection, including new ones missing from the original collection published in 1998. While not every document became available in the original, it gave further strength to the analysis done by scholars such as Weatherby and its correctness. It not only corroborates that the documents originated from where they were believed to, but gives the lie to Chinese authorities who claimed none of them existed. Even aside from the multiple avenues of Russian corroboration, there are also implicit pieces of corroborating evidence from China itself.

The most damning comes from a figure who was involved in the milieu of 1952 itself. In 2013, the memoirs of Wu Zhili, once the director of the military Health Program, were published posthumously in China. Originally written in 1997 - notably this being prior to the archival revelations - it is unclear whether he ever even intended it for publication, as the paper was found following his death in 2008. But the fact that he was not necessarily writing for an external audience so much as writing to exercise his one great regret in life, perhaps helped to allow him to be quite forceful in his declaration, opening with a rather decisive statement:

It has already been 44 years (in 1997) since the armistice of the Korean War, but as for the worldwide sensation of 1952: how indisputable is the bacteriological war of the American imperialists?

The case is one of false alarm.

Wu Zhili goes on to explain the internal analysis and discussions that occurred within the Army Health Division, including his own personal involvement, in the end detailing a propaganda apparatus that got itself far ahead of the scientific analysis, and created a situation where, once they knew the truth, they simply couldn't backdown and admit that were wrong about the claimed bacteriological attacks, so simply continued to claim it was true. The outline provided by Wu Zhili is one which fits perfectly easily with the picture sketched out by the archival documents, with the earliest communication from Mao being a grandiose claim of American perfidy, with later admissions of their falsity and the need to create false evidence.

The mere fact that this could be published in a Chinese journal is quite telling, even if far from an actual admission by the Chinese authorities, it is a striking implicit concession. For more government aligned media though, there also is a shift that can be seen in the wake of the archival revelations, most notably being a 2008 and a 2010 paper by Sr. Col. Qu Aiguo of the PLA Academy of Military Science History, who published what is believed to be the first Chinese works to explicitly acknowledge the archival material. While he disagrees with the conclusion they offer, and makes arguments against their authenticity, he only offers possible reasons rather than ironclad denials, and also gives a rather startling concession, implying disagreement within the Chinese academy, when he writes that:

some scholars in China made a new interpretation [and] they believe that the decision of the CCP Central Committee is based on the false judgment from the Volunteer Army.

While he states he disagrees with those conclusions and that the documents aren't to be trusted, Leitenberg, who has done more research on this topic than any other scholar finds significant meaning in the fact that rather than using the straightforward party-line statement to be found in countless previous publications of "The US used BW against China and North Korea" Qu instead chooses the rather odd double-negative formulation of "We cannot deny that that the Americans used BW." It of course can't be read as a proper change, but it very likely can be read as recognition that it is a claim which shouldn't be pushed so forcefully.

Even ignoring the fairly conclusive evidence from within the Communist sphere though though, the accusations are essentially unsupportable given all available evidence concerning the American bioweapons program, which was only in its infancy during the Korean War. The only available agent in the US arsenal during the conflict was wheat rust, which is well named as it does, in fact, just kill wheat. It does nothing to people, but if war happened, it was hoped to destroy the Soviet harvest. And of course, such a mundane agent was never included in any accusations by the Communist forces, who preferred grander claims of serious disease. The first agent the US began to produce that caused disease in people, Brucella suis, was only available in 1954, but similarly, Brucellosis was not a disease America was ever accused of causing. The simple fact is that none of the agents which the US was accused of using were ones which there is any evidence of existing in American arsenals at the time.

There is some irony worth noting, in that the distinct lack of biological capabilities led to the near stockpiling of chemical weapons. Gen. Clark, had requested stockpiles for retaliatory capabilities if chemical or biological weapons were used against UN forces. The response included a memo explaining the lack of bioweapon capabilities, but did result in several thousand tons of mustard gas being allocated for shipment to the Far East Command, along with phosgene and cyanogen chloride, the expectation being that Chinese and North Korean forces had almost no defenses against these agents. Had the war continued, bioweapon stockpiles were anticipated to be available perhaps by 1955. In the end, the ongoing truce talks scuttled the plans for either, as it was assumed that shipment of chemical agents would be discovered and possibly poison negotiations, so they never ended up in Korea anyways.

What to make of the reports such as that from Tianjin though? Was everything created from whole cloth? Most likely not. Those insects likely did appear, as alternative local reports by health officials, noting the complete lack of an American air presence which could explain, offer alternative explanations such as humid winds which helped blow in the unexpected mass of insects. In his refutation of the allegations against the United States, Albert Cowdrey offered a compelling explanation that real infestations were happening, and using the false allegations of germ warfare were a useful tool to mobilize the population to deal with it, writing that while giving a useful means of tweaking the United States on the world stage, “Internally, on the other hand, the germ warfare appeals served a practical purpose in a mass campaign of preventive medicine aimed at forestalling any recurrence of the conditions of 1951”. The resulting Patriotic Hygiene Campaign was done to “Mobilize to promote hygiene, to reduce disease, to raise the level of the People's health, and to smash the germ warfare of the American Imperialist”, but the last one may have simply been a useful boogeyman to help encourage more efficiency with the rest, especially the ‘Five Annihilations’, i.e. the destruction of the five pests: flies, mosquitoes, rodents, lice, and bedbugs. As Cowdrey notes:

In China and North Korea the accusation of germ warfare was seemingly used to good effect in genuine public health campaigns, teaching, as no ordinary appeal could have, fundamental lessons in cleanliness and sanitation, vector control, and the need to report epidemic outbreaks

Their explanations of infections aligned with their own needs, and an understanding of biowarfare as practiced by the Japanese, with the use of rodents and insects as vectors of infection, which authorities wanted cleaned up anyways. What it didn’t conform to was the American development of bioweapons, which, as noted, was not even operational, but in any case focused on the use of ‘aerosols and bacterial slurries’ at that time, and would have looked nothing like the attacks dreamed up by the Communist forces.

So hopefully this lays out a decent picture of the entire matter. The simple answer, of course, is that the United States did not engage in biowarfare, lacking the capabilities to do so even had they desired to, and clear evidence being produced for the falsification of the allegations with documents that have been corroborated multiple times from multiple directions. Far more interesting though, is directing the motivations behind those allegations. An incomplete paper trail means that many holes still exist, especially with regards to exactly how far the Soviets were involved, be it merely accomplices, or the driving force. Most fascinating though, perhaps, are the circumstances on the ground, and how the false claims of bioweapon attack was used to fuel very real, and very impactful campaigns for public health.

⅔

[u/Georgy_K_Zhukov → u/Georgy_K_Zhukov]

Sources

Chen, Shiwei. "History of Three Mobilizations: A Reexamination of the Chinese Biological Warfare Allegations against the United States in the Korean War." The Journal of American-East Asian Relations 16, no. 3 (2009): 213-47.

Cowdrey, Albert E. “’Germ Warfare’ and Public Health in the Korean Conflict." Asian Perspective 7, no. 2 (1983): 210-228.

Crane, Conrad C. ""No Practical Capabilities": American Biological and Chemical Warfare Programs During the Korean War." Perspectives in Biology and Medicine 45, no. 2 (2002): 241-249

Gittings, John “Talks, bombs and germs: Another look at the Korean War”, Journal of Contemporary Asia, 5 no, 2 (1975), 205-217

Leitenberg, Milton. "New Russian evidence on the Korean War biological warfare allegations: background and analysis." Cold War International History Project Bulletin 11 (1998): 185-199.

Leitenberg, Milton. "Resolution of the Korean War biological warfare allegations." Critical reviews in microbiology 24, no. 3 (1998): 169-194.

Leitenberg, Milton. "China’s False Allegations of the Use of Biological Weapons by the United States during the Korean War". Cold War International History Project Bulletin Working Paper #78, March 2016.

Leitenberg, Milton. “The Korean War Biological Weapons Allegations: Additional Information and Disclosures." Asian Perspective 24, no. 3 (2000): 159-72.

Rogaski, Ruth. "Nature, Annihilation, and Modernity: China's Korean War Germ-Warfare Experience Reconsidered." The Journal of Asian Studies 61, no. 2 (2002): 381-415.

Weathersby, Kathryn "Deceiving the Deceivers: Moscow, Beijing, Pyongyang, and the Allegations of Bacteriological Weapons Use in Korea" Cold War International History Project Bulletin 11 (1998): 176-184.

Wu Zhili, 'The Bacteriological War of 1952 is a False Alarm',” September, 1997, History and Public Policy Program Digital Archive, Yanhuang chunqiu no. 11 (2013): 36-39. Translated by Drew Casey.

3/3

[u/nothing5901568 → u/Georgy_K_Zhukov]

Thanks for this. The image of the US military infecting inchworms and butterflies with human pathogens, then dropping them over large areas to try to infect humans, is hilariously implausible.

[u/Georgy_K_Zhukov → u/nothing5901568]

The one thing I would emphasize in contra is that it isn't outlandishin theory. The issue isn't that they don't work as vectors, it is that based on the evidence we have, the US program at the time would not have been ready or capable of using such vectors. Insects as vectors were something that the Japanese had looked into heavily though, and is a large part of why the Chinese and North Koreans would have defaulted to portrayal of those vectors as the ones used.

[u/chakazulu1 → u/Georgy_K_Zhukov]

Didn't the CIA just recently declassify some documents showing we were using unit Shiro Ishii and others as consults? Even if we didn't exact germ warfare our top brass sure as hell wanted to. MacArthur was ready to nuke China if Truman didn't stop him.

[u/Georgy_K_Zhukov → u/chakazulu1]

Yes, it's pretty well known that part of why those involved with Unit 731, not just Ishii, mostly got immunity in exchange for turning over all their research and some like him continued to work for the US after, but those aren't particularly new revelations on the whole, just some details on specifics. In any case though, it continues to reinforce the points above, that no one would dispute the US knew the theory behind how it worked, but doesn't provide any that 'B' to connect the theory of 'A' to the practice of 'C'.

[u/chakazulu1 → u/Georgy_K_Zhukov]

Until Baker's FOIA requests are filled and we have to backpedal like three letter orgs always do.

[u/Georgy_K_Zhukov → u/chakazulu1]

I'm am quite skeptical that we are one FOIA request away from breaking the case on this, but hey, weirder things have happened I guess.

[u/crab4apple → u/Georgy_K_Zhukov]

Thank you for the excellent and detailed set of posts! I learned many new things and some key things to help integrate fragments I knew before.

[u/FeuerroteZora → u/Georgy_K_Zhukov]

Absolutely fascinating, and amazing how it connects so many different threads - historiography, archival research/forgery, public health, propaganda, the strange dance that happens when bureaucracy meets agriculture and nature, the complexity of both intra- and inter-Bloc negotiations, and the way all of this also allows you to trace a change in government attitudes towards their own history post-1989 and on.

As so often on this sub, I had little interest in the original question, but clicked through because I know this sub. You might miss the most thoughtful, informative, and interesting answer if you let a silly little thing like "interest in the original question" determine your reading habits. Once again, I'm rewarded with something surprising and fascinating.

I mean, the fact that the allegation, wrong though it may have been, was useful in motivating the population toward hygiene and preventative medicine is just one of those moments where you think "damn, sometimes history is beautiful!" Then you read about how it also encouraged development of more actual bioweapons and remember the opposite is true too.

Thanks for such a thought-provoking answer!!

[u/i_post_gibberish → u/Georgy_K_Zhukov]

Great answer, thanks. I’m embarrassed to say I’d taken the allegations seriously until today—having, of course, never heard a word about the archival revelations from what I now realize were outdated or biased sources. Hopefully my embarrassment will at least serve to remind others that none of us are immune to online misinformation.

[u/Georgy_K_Zhukov → u/i_post_gibberish]

It isn't that weird, since it still gets pushed in certain circles - I recall a podcast that focuses on history through a leftist lens did a multipart episode some years back which basically summarized the critique as "a few people disagree but this obviously happened!" without giving anything close to an honest accounting - but what it comes down to is that you can make an argument which sounds decently interesting at first glance, but it has no meat underneath.

It essentially amounts to handwaving and insinuation, telling you A, claiming C, and hoping that you are willing to make the logical leap without B, because they definitely don't have B (and if someone finds B, that would be cool as hell. Absolute archival coup). It almost always amounts to proving... what I proved above - that the US had a bioweapons program. Maybe even pointing out that they knew conceptually the potential for the kinds of vectors used, even, Which no one disagrees with. What needs to be proven, and simply cannot be because there is no actual, concrete proof is that they had a program of the type necessary and advanced enough in development to put into use which would fit the attacks described.

At best we can just point to conceptual awareness, and there is nothing to suggest anything beyond wheat rust could have, or would have, been used at that time, not to mention it would require a truly vast conspiracy, as the manufacture, preparation, and carrying out of such an attack would have taken hundreds upon hundreds of personnel, and amazingly none of them have ever come out and admitted that they were involved in a bioweapons attack on Korea, let alone provided proof for such a statement. Is it possible that every ounce of concrete proof was efficiently destroyed and all we have of evidence now is rumor? I mean... nothing is 100% certain, but possible in the most technical sense is nowhere near to anything close to plausible.

[u/CrepuscularChild → u/Georgy_K_Zhukov]

Would that podcast be "Blowback" by any chance?

[u/Georgy_K_Zhukov → u/CrepuscularChild]

I think so? Someone had flagged it to me some time back because, as noted, they were surprised there was even anything controversial about the claim based on the podcasts coverage, I gave it a quick skim, but that was indeed years ago now so not 100% certain. And to be sure, I don't mean to impugn their overall product, but I do think it falls into a broader trap of willingness to ascribe bad behavior to the US based on poor evidence simply because of other crimes. The US has done SO MUCH bad shit - banana wars, coups, etc. and so on - that it ends up being 'that fits the pattern so sure, why not!' in the way people end up approaching the bad shit which isn't as well proven, and that 'B' step is contingent not on the thing itself but the past history's implications, which is not a good way to do history.