Lessons from the First Time Russia Accused the United States of Biowarfare

korean war march

Editor’s note: Don’t miss our comprehensive guide to Russia’s war against Ukraine.


As Russian forces face continued setbacks in their invasion of Ukraine, Moscow has intensified unfounded accusations that the United States is planning to launch biological attacks from Ukrainian territory. More than 70 years ago, the United States faced similar accusations in Korea.

In 1951, negotiations to end the Korean War intensified as fighting on the front lines reached a stalemate. With major ground offensives no longer an option, each side developed a different approach to secure its desired political outcome at the peace table. For U.N. forces, their primary coercive tool became American airpower in an extensive bombing campaign that eventually laid waste to most of North Korea. The communist side resorted to information warfare: they fomented riots in the Koje-Do prisoner-of-war camps to highlight alleged prisoner abuses and accused American airmen of biological warfare against North Korea and China. The latter tactic was designed to embarrass the United States as well as discredit and perhaps restrain the application of its punishing airpower. The Soviet Union supported the communist biological warfare information effort until deciding, in the spring of 1953, that it needed an armistice, while also realizing the campaign was based on falsified information. To this day, however, many in China still believe the allegations.



This part of Korean War history can shed light on the motives and strategies driving Russian accusations today, as well as the options available for Washington to counter them. If Russia chooses to pursue these allegations further, U.S. policymakers should expect outlandish claims, falsified evidence, Russian-orchestrated investigations, and perhaps even forced confessions. Moscow may be seeking a pretext to use chemical or biological weapons itself, or simply trying to put the United States on the defensive in the international arena. These claims may also be motivated by the need to justify the invasion of Ukraine in the eyes of a domestic audience.

During the Korean War, Washington mounted an effective response that succeeded in discrediting communist allegations in most of the world, if not within communist countries themselves. The key to this success was responding to the accusations directly, bringing diplomats and scientists together to investigate and refute false claims.

Communist Accusations     

During the Korean War, the Chinese and North Korean governments tried to blunt the impact of superior American technology by directing propaganda against it. Bombing in general, and the threat of atomic weapons in particular, were portrayed as immoral attacks on civilians in violation of the laws of warfare. One additional aspect of communist propaganda that caused special concern for American leaders involved accusations of chemical and biological warfare. Even today, some Chinese historians such as Qi Dexue still argue that their government had valid evidence of germ warfare, and that relevant U.S. documents still need to be declassified. While most files dealing with nuclear issues during that period are, in fact, still classified, that is not generally the case with chemical and biological records. An examination of the pertinent documents is very revealing, not only about the sensitivity of the United States to charges of employing chemical and biological weapons, but also about its remarkably unsuccessful early efforts to develop non-nuclear weapons of mass destruction. While skillful communist propaganda kept American diplomats on the defensive, American military forces in the Far East possessed neither the ability, nor the will, to apply these weapons in the offensive fashion described in enemy propaganda.

Communist bloc allegations about U.S. bacteriological warfare research dated back at least to 1949, while the first charges of biological weapons use were made in 1950. The United Nations struck back in November by telling the United Press that in 1947 advancing U.N. troops had discovered a “super-secret bacteriological laboratory” in Pyongyang run by a Russian female scientist. Though only about 400 starved rats were found in the facility, a North Korean doctor revealed that over 5,000 had been inoculated there with deadly diseases and then sprayed with a chemical that encouraged the multiplication of fleas. The Russian supervisor disappeared, supposedly leaving with other fleeing communist officials.

The communist propaganda campaign expanded in 1951. In February, North Korea claimed that retreating U.S. troops had spread smallpox behind them in December 1950, and the foreign minister filed a protest in the U.N. General Assembly in May. During the summer, North Korean radio announced the country was beginning anti-epidemic measures because of U.N. biological attacks.

This was all just a prelude to the most vehement, and effective, biological weapons propaganda campaign that began in early 1952. On Feb. 22, the North Korean foreign minister announced that the United States was carrying out biological warfare against his country. During the same period, Chinese press and radio made repeated references to the fact that the United States had granted immunity to Lt. Gen. Shiro Ishii and his subordinates, who, as part of the notorious Unit 731, had conducted biological weapons experiments in China during World War II. Washington had, in fact, made this morally questionable decision in exchange for information derived from Japan’s biological weapons program, which provided some benefit for American researchers working on biological agents and vaccines.

On March 6, Chinese newspapers reported that 448 American aircraft had flown biological weapons missions over Manchuria during the preceding week. Two days later, the U.S. Department of State Monitoring Service and the Foreign Broadcasting Intelligence Service picked up a radio broadcast by Chinese Foreign Minister Chou En Lai decrying the biological weapons campaign as an attempt to wreck the armistice talks. He also announced that “members of the U.S. Air Force who invade Chinese territorial air and use biological weapons will be dealt with as war criminals.” At the same time, the Central Intelligence Agency received an unconfirmed report that North Korea and China were preparing fallacious documentation to justify punitive action against the next captured pilot. The Chinese and Soviet press followed by publishing pictures of insects and germ bombs supposedly dropped by American planes over North Korea — though scientists asked to examine the images by the New York Times easily refuted their credibility.

Reactions to the Charges

Chou En Lai’s statement caused a furor in Washington. The Joint Chiefs of Staff and the State Department advised Gen. Matthew B. Ridgway, commander of all U.N. forces in Korea, to strongly deny the charges and also to warn the Chinese and North Korean governments not to mistreat prisoners of war. Ridgway decided not to deliver the statement, since he believed he had already issued enough vigorous denials. In addition to this action, the State Department got the International Committee of the Red Cross to agree to conduct an investigation of the allegations, and accepted a similar offer to investigate from the World Health Organization. While Soviet representatives at the United Nations repeated the accusations and emphasized that the United States had not ratified the 1925 Geneva Protocol against biological and chemical warfare, they also vetoed U.S. resolutions that would have permitted the International Committee of the Red Cross and the World Health Organization to conduct inspections. The Chinese government also refused independent offers from those organizations, claiming they were only interested in securing military intelligence for the United States. Beijing asserted that proper investigations were already being conducted by “friendly governments.” Soviet newspapers then expanded their accusations to blame the United States for hoof-and-mouth disease in Canada and a plague of locusts in the Near East.

Secretary of the Air Force Thomas Finletter told the secretary of defense that his service believed the propaganda was designed either to discourage U.S. exploitation of the “great military potentialities of BW-CW weapons,” or to set the stage so the communists could use their own biological and chemical capability in a “Pearl Harbor” surprise attack. Though the first assumption was most likely, the second was most dangerous, and Finletter had his surgeon general inventory supplies of vaccines and antibiotics. U.S. Far East Command in Korea shared the Air Force’s concerns, expanding its biological weapons detection and prevention programs while requesting biological and chemical munitions for retaliation. While fears of communist attacks fueled a significant increase in American biological weapon programs, these did not produce results until 1954.

At the United Nations, Washington followed a carefully planned strategy developed by Assistant Secretary of State for U.N. Affairs John Hickerson to discredit the communist charges. Hickerson knew that Soviet representative Jacob Malik would assume the U.N. Security Council presidency in June 1952. Hickerson was also aware that Malik wanted to debate the question of bacteriological warfare. Hickerson prepared two draft resolutions to introduce when Malik brought up the issue. The first proposed the creation of an impartial commission of inquiry. Hickerson expected that to be vetoed by the Soviet Union, so his subsequent resolution condemned them for frustrating the investigation. He knew that proposal would meet the same fate as its predecessor but believed the vetoes would expose communist insincerity to all but the most biased observers, thereby providing positive publicity for the American position. When Malik repeated the accusations on June 18 and submitted a draft resolution calling for all states to ratify the 1925 Geneva Protocol prohibiting biological warfare, U.S. Deputy Representative to the United Nations Ernest Gross was ready to reply. He gave a lengthy explanation of U.S. motives, insisted on America’s innocence, condemned the Soviet Union for its own work on bacteriological warfare, and circulated a draft resolution permitting the International Committee of the Red Cross to conduct an impartial investigation of all the communist accusations. The Security Council rejected Malik’s resolution and his attempts to bring North Korea and China into the debate, and instead focused on the American proposal. When a vote was scheduled, Malik cast the lone dissent, as expected. Gross then introduced the second resolution recognizing the offers to help from the International Committee of the Red Cross and the World Health Organization, condemning the Soviet veto, and concluding from their refusal to allow the impartial investigation that the communist charges “must be presumed to be without substance and false.” The Security Council vote on that resolution was 9-1-1, with Pakistan abstaining and the Soviet Union casting its 50th veto. Though the resolutions were defeated, the United States did gain in public relations. Press coverage emphasized Soviet intransigence, and Gross was featured in newsreels condemning the “false and malicious” charges of the “Red” campaign.

The accusations of germ warfare were echoed in the Eastern European press and had some impact in Asia, especially in India and Pakistan. There, the charges reinforced suspicions about American treatment of the “colored peoples of Asia” and the belief that the United States “by its actions and failure to act” was prolonging a struggle that might develop into World War III. Whether major communist bloc leaders really believed that China and North Korea were the target of a bacteriological warfare campaign or not, they had little incentive to thoroughly investigate the accusations coming from field commanders so long as the propaganda campaign seemed to be garnering support at home and abroad.

Ironically, recent revelations from Russian archives strongly support the argument that mid-level Chinese and Russian operatives had cooperated with the North Korean government to fake evidence. Their efforts included creating false infestation maps, gathering cholera and plague bacillus from infected people in North Korea and China, injecting condemned prisoners with the diseases, and burying infected bodies that could be found to support their epidemic claims. In 1952, this campaign was intended to convince two carefully chosen groups of observers — the International Association of Democratic Lawyers and the International Scientific Commission for the Investigation of the Facts Concerning Bacteriological Warfare in Korea and China — that the United States was indeed using germ warfare. However, by April 1953 the post-Stalin government in Moscow had found out about the fabrication of evidence and determined that the claims concerning the use of chemical and biological weapons by U.S. forces were false. Fearing that revelations of the deception could be embarrassing and cause “political damage,” especially since an armistice was now desired, Soviet representatives “recommended” to China and North Korea that they curtail their campaign, and the accusations promptly ceased.

The most significant effect of the germ warfare propaganda was on the North Korean and Chinese home fronts. Ordinary citizens and soldiers took the biological weapons charges very seriously, becoming more motivated to fight and support public health programs. Allegations that American aircraft were releasing smallpox and typhus germs could also cause Chinese troops to panic, however. The situation was worsened by outbreaks of cholera, plague, and meningitis, which the troops also assumed had been caused by the enemy, but were really just a part of the normal spring epidemic season. In March, the Chinese government launched a “patriotic health and epidemic prevention campaign” and asked citizens to kill insects and clean cities and roads. Millions of civilians were vaccinated, as were over 90% of front line troops. The result of the sanitation and health drives was a significant decrease in infectious diseases that allowed communist officials to declare victory over American biological weapons technology, while propaganda continued to keep the United Nations on the defensive in treaty negotiations. The campaign also inflamed the civilian population in North Korea so much that they went out of their way to hunt downed American aviators, ensuring that these men had virtually no chance to evade immediate capture.

Prisoner Confessions

A new ingredient was added to the communist propaganda campaign in early May 1952. Radio Peking and Pravda provided excerpts from the confessions of two American airmen: 1st Lt. John S. Quinn, a B-26 pilot, and 1st Lt. Kenneth L. Enoch, his navigator, admitted that they had been forced to drop “germ bombs” by the “warmongers of Wall Street” as part of an extensive biological weapons effort against China and North Korea. Eventually, as many as 38 flyers would confess to participation in biological warfare, eight of whom were heavily featured in communist propaganda films and broadcasts during 1952. The State Department denied their claims, asserting the statements had been induced by torture and brainwashing, while the Air Force painstakingly investigated every aspect of the confessions. They found enough inconsistencies to believe that the officers concerned had not caved in completely, though the discrepancies could not be released immediately to discredit the statements because of fears the communists would then harm the officers or use the information to refine interrogation techniques. In March 1953, the Air Force and Marine Corps did furnish declassified information to the U.S. delegation at the United Nations for use in “an aggressive countercharge” there.

The Air Force had some public relations plans of its own to supplement the theme of “forced false confessions” being promulgated by the State Department through their Voice of America and international press facilities. The service prepared its own film to counter the germ warfare charges, but the Department of Defense did not approve its release. As the possibility for an armistice grew, so did the Air Force’s hopes they could recover the airmen and have them recant their confessions. Until the last minute though, there were fears that the North Korean and Chinese governments would not return them for this very reason. General Mark Clark, who succeeded Ridgway as U.N. commander in Korea, received special instructions to demand accountability for the Marine and Air Force officers involved in the confessions if they were not repatriated. He was even authorized to initiate “clandestine and covert activities” to find them and get them back.

However, none of that was necessary. Five of the airmen arrived back in San Francisco in September 1953, where a representative from the U.S. Air Force Psychological Warfare Division gathered written statements and made film and tape recordings. All the returnees claimed they had been coerced by mental and physical torture including threats of death. Copies of the statements were given to the U.S. delegation at the United Nations, while some film footage was provided to newsreels. Their coverage juxtaposed clips from the communist movies with Air Force footage of the repatriated prisoners of war talking about torture and threats to show how the “big lie technique spawned by Hitler was brought up to date by the Reds.” At the United Nations in late October that same year, the U.S. delegation presented the sworn statements and mounted a spirited attack on the communist abuse of prisoners of war while denying all the biological warfare accusations. Accounts of prisoner abuses and forced confessions also ran in major newspapers such as the New York Times.


Russian accusations today reflect many of the same motives and tactics that drove communist charges in Korea. Indeed, one enduring legacy of these charges is a lingering suspicion in Russia and Asia that the United States would all too willingly use chemical and biological weapons.

As with most persistent conspiracy theories, the communist allegations had some basis in truth. The regrettable deal with Lt. Gen. Ishii at the end of World War II provided the foundation for the Korean War allegations. Despite the diligent efforts of many researchers, no evidence has ever been found to support claims of American biological warfare in Korea or China. It is not beyond the realm of possibility that there could have been some sort of false flag operation or laboratory mistake involved.

Today, there is an even more innocent grain of truth: a U.S. agreement with Ukrainian biological research facilities beginning in 2005, which was designed to actually prevent the development of any weapons. The international and media environments have also changed considerably since the Korean War. For one thing, even some mainstream American media outlets, such as Fox News, have echoed accusations about the biological warfare labs in Ukraine.

But American leaders can also learn from the response that Washington mounted in 1952 and 1953. This experience suggests they should be prepared to meet escalating accusations with an immediate and strong response, both in international bodies like the United Nations and in the public press. Rather than let accusations fester, thorough investigations can help provide verifiable and convincing evidence to refute hostile claims.



Conrad Crane, Ph.D., is a research historian at the Army War College. He has written widely on airpower and land-power issues. His two latest books are American Airpower Strategy in World War II, published by University Press of Kansas, and Cassandra in Oz: Counterinsurgency and Future War, from Naval Institute Press. 

The views expressed in this essay are those of the author and do not necessarily reflect the official policy or position of the Army, Department of Defense, or the U.S. government. The author also has no special access to intelligence or any operational matters that are not otherwise available to the general public.

Image: U.S. National Archives (Photo by Army Signal Corps Collection)