Can we end biological weapons?

Sadly, biological weapons are back in the news. On the 11th of March, Russia's representative told the United Nations' security council that Russia had uncovered evidence of Ukraine developing biological weapons with the aid of the United States. Naturally, Ukraine and the US deny the allegations. The US representative suggested this might signal that The Kremlin is planning to use a ‘false flag’ tactic to cover their own use of biological weapons.

If this happens, it would break an important norm in global warfare and contravene the Biological Weapons Convention (BWC). In this post I want to explore why this might be a big deal, something distinct from the horror that’s already unfolded in Ukraine, and why it’s important to end the development of biological weapons.

To do this I’ll explore:

  • The history of bioweapons and the BWC.
  • Why biological weapons are particularly bad, using some basics of just war theory.
  • What we might be able to do about this.

I’ll say upfront I’m not an expert on these topics and I have no direct experience working on the BWC. But I think this is something that people working in public health should care about and take the time to understand, because ultimately this is about preventing disease and protecting health. Throughout the post I’ll direct you towards resources from actual experts in case you want to learn more.

A very brief history of biological weapons and the BWC

Biological warfare has a long and ugly history. Some of the first instances of biological warfare are thought to have involved catapulting corpses over the walls of besieged cities. The memoir of a 14th Century Italian notary describes a Mongol army doing just this after a plague epidemic interrupted their siege of Caffa (modern-day Crimea) in 1346. Four hundred years later the British used a similar tactic when they handed small-pox infested blankets to Native American tribes [1]. The development of scientific understanding of microbiology and disease that arose in the 19th Century set the stage for more sophisticated approaches to biological warfare.

The German army began experimenting with biological warfare during World War I, but chemical weapons were a far more prominent feature of this war. The horror of these weapons led to the development of the Geneva Protocol in 1925, which banned the use of “poisonous, asphyxiating or other gases” and bacteriological warfare. The protocol initially did not include mention of bacteriological warfare, but Poland suggested this addition, arguing that these weapons can be as horrific as chemical weapons.

The Geneva Protocol only prohibits the use of biological weapons, and not their development or stockpiling. During World War II many countries developed significant biowarfare programs. Japan conducted several bioweapons attacks against China and had an infamously cruel bioweapons development program involving testing on Chinese prisoners. The Allies also invested in biowarfare, reportedly motivated by a concern that Germany was developing a bioweapons program. By the end of World War II, many countries had substantial biowarfare programs.

In the 1960's (possibly prompted by the Cuban Missile Crisis) there was a renewed interest in enhancing international security through disarmament and cooperation. Ultimately this led to the development and signing of the Treaty on Non-Proliferation of Nuclear Weapons in 1968, the BWC in 1972, and the Chemical Weapons Convention in 1997.

The BWC is a legally-binding agreement by signatory states to not develop, produce, stockpile or acquire biological or toxin weapons. This also required countries to destroy any existing stockpiles that could be considered biological weapons. The full wording of the convention can be found here. The BWC entered into force on the 26th of March 1975, and currently has 183 state parties, including the big military powers China, Russia, and the United States.

The BWC isn’t just a passive agreement to set and forget. State parties are required to take active measures to implement the treaty and prevent the development of biological weapons within their borders. There are five-yearly review meetings and more regular meetings of technical experts. State parties must also produce annual reports on so-called confidence building measures (CBMs). These were introduced in 1986 with the aim of reducing suspicion and building trust between parties. These have been updated over the years and currently include things like:

  • reporting on the number of relevant laboratories and research centres,
  • exchanging information on outbreaks of infectious disease, and
  • reporting new legislation and regulations brought in to support implementation.

There is a fair amount of work that goes into implementing the BWC. In addition to the efforts of the state parties, there is a lot of coordination that needs to be done, like arranging and running the meetings, distributing CBM reports, assisting countries with implementation, and encouraging ratification by countries who aren’t yet signatories. This is done by the Implementation Support Unit, a four-person team located in the Geneva Branch of the United Nations Office for Disarmament Affairs.

Problems facing the BWC

While this widespread agreement not to develop or use biological weapons is heartening, there are concerns that the BWC lacks teeth. After all, only four people are responsible for ensuring this international treaty between 183 countries is honoured and implemented. As a comparison, the Organisation for the Prohibition of Chemical Weapons has about 500 staff members. The mandates of these two groups seem very similar.

In addition to limitations of the BWC’s small staff, it has been difficult for state parties to agree on a protocol for verifying compliance with the convention. And unfortunately, there are good reasons to doubt that all parties are honouring the BWC.

In 1992 then-President of the Russian Federation, Boris Yeltsin, acknowledged that the USSR had been running an offensive bioweapons development program when he decreed that the program should be halted. Western understanding of the program has largely been pieced together from the testimony of defectors, so the full scale of the program is unclear. However, the program likely employed tens of thousands of people, making it thought to be the largest offensive bioweapons program in history.[2]

Iraq and South Africa also developed offensive bioweapons programs after signing the BWC. Iraq’s bioweapons program involved large quantities of botulinum toxin and anthrax and was ultimately detected by UN inspectors in 1995. Project Coast, as South Africa’s bioweapons program was known, was highly secretive and much smaller scale, aimed at assassinating political figures rather than causing mass casualty.

This means that we know that for close to twenty years, several signatories were acting in violation of the BWC. There is also suspicion that other parties have their own covert bioweapons programs. Clearly, not having a mechanism to determine if state parties are compliant with the convention severely undermines its force. This brings us back to verification.

Throughout the history of the convention there has been disagreement between state parties about how to go about verifying the BWC [3], so no system has been implemented. This is again in contrast to the Chemical Weapons Convention, which includes a Verification Annex that sets out a process for inspections to monitor compliance and respond to any alleged use of chemical weapons.

In the early 1990’s efforts began to develop a protocol for verification, which was led by the purpose-made VEREX committee. Unfortunately, VEREX failed to develop a protocol acceptable to all parties, however they may have had an impossible task.

King’s College London academic, Dr Filippa Lentzos, describes the challenge of verification in a 2013 policy brief. Firstly, it is difficult to recognise a bioweapons program through inspections. Even large amounts of biowarfare agents don’t take up a lot of space and could be spread across facilities. It's also very difficult to distinguish between research for defensive purposes, research for offensive purposes, and industrial pharmaceutical development. Some opposition to verification processes has been due to concern for protecting the intellectual property of industry.

When the VEREX protocol was discussed at the Fifth BWC Review Conference in 2001, the United States rejected it for not being rigorous enough to detect bioweapons programs, but invasive enough to jeopardise the confidentiality of biodefense and pharmaceutical industry activities. Many other states had similar concerns and there was widespread disagreement on the proposed system of verification and the procedural report of the VEREX process. Multiple sources describe this meeting ending in acrimony [4], with this fueled by the disagreement between state parties, and lit on fire by the US proposing to terminate attempts at verification less than two hours before the end of the conference.

Why the fuss about biological weapons?

You might wonder why there is such a special focus on biological weapons in particular. Many weapons can cause horrific damage to human bodies, so why does this class of weapon demand a special approach? Even if the entire enterprise of war is reprehensible, once it’s started and people are engaging in the activity of systematically killing other human beings does it really make a difference how they do that? Is all fair in love and war?

To answer this, I think it’s helpful to take a short detour into just war theory.

There is a strong intellectual history of pacifism, arguing that war, and other forms of violence, is never justified. And when you consider the horror that has occurred in wars throughout human history this position seems pretty intuitive. To be honest I am drawn to it. The non-violence practiced by Mahatma Gandhi and Martin Luther King Jr. is certainly inspiring and led to substantial changes to oppressive systems. There are lots of examples in history where responding to violence with violence has resulted in escalating brutality and immense loss and suffering. Maybe the Buddha was right when he said that hatred doesn’t cease through hatred, only through love.

But, many people, including some who have been advocates for non-violent resistance, like Nelson Mandela, have ultimately come to the conclusion that violence can sometimes be necessary. Mandela was originally an admirer of Gandhi’s approach, but ultimately advocated for non-peaceful means of resistance when non-violence wasn’t producing results. There are other instances where it seems difficult to imagine that the right response was to not intervene with force. Despite the horror of World War II, it seems unconscionable that the Nazis and the German army be allowed to continue the Holocaust and their expansion across Europe.

That some wars might indeed be just is the motivation for what’s been called the just war tradition in military ethics. I’m not going to be able to do justice to the long history of thought in this area [5], but I can give a quick overview of some of the main points.

Traditionally theorists have divided conditions for a just war into those that determine when it is appropriate to start a war and those that deal with appropriate conduct in war. For some reason [6], the Latin names are used to describe these in contemporary scholarship, jus ad bellum and jus in bello [7], respectively.

Traditional accounts of jus ad bellum suggest that for a war to be just it must:

  • be fought for a just cause.
  • be the last resort for achieving that cause.
  • be proportionate to that cause.
  • be waged by a legitimate authority.
  • be fought with the right intention.
  • have a reasonable prospect of success.

And traditional accounts of jus in bello suggest that a just war must be conducted in a manner that:

  • distinguishes between combatants and non-combatants.
  • causes the minimum harm necessary for military advantage.
  • only cause harm that is proportionate.

Of course, there is substantial debate about these criteria, including whether they’re each necessary and collectively sufficient for a war to be considered just, as well as their interpretation. But they have been influential in how we think about war and war crimes.

How do bioweapons measure up to these criteria? It seems possible that a bioweapon using a non-contagious biological agent could meet the jus in bello criteria. Some agents, such as anthrax, do not spread between people and so they will only harm those who come into direct contact with them. I don’t mean in any way to condone their use, which still seems reprehensible, but this suggests they might plausibly distinguish between combatants and non-combatants and potentially cause a minimum and proportionate amount of harm. Of course, a weapon that distributed large quantities of non-contagious agents over a large civilian area would likely not meet these criteria.

What seems clear though, is that bioweapons involving contagious agents will fail to meet the jus in bello criteria [8]. Contagious agents are incapable of distinguishing between combatants and non-combatants. Even if the release is concentrated on a place with few non-combatants (e.g. a military base) it will likely spread to non-combatants, especially if the combatants seek medical care, bringing infection to health care facilities. This lack of control over where a biological agent spreads also suggests that bioweapons are likely to fail the other two criteria. With a contagious agent there is little ability to titrate the harm caused to the minimum amount necessary or to what would be considered proportionate to the cause that prompted the war.

What’s more, it’s possible that contagious biological weapons could become weapons of mass destruction, posing a global catastrophic risk. It’s worth remembering that the 1918 influenza pandemic is believed to have caused more deaths than all military and civilian casualties in World War I [9]. COVID-19 has reminded us of the devastation that a pandemic can cause, and there is a real worry that biotechnologies may make a pandemic caused by bioweapons an even more catastrophic event, one that may threaten civilizational collapse or possibly the extinction of humanity. This isn’t a proportionate response to any war, for any cause, no matter how just.

So it seems that all isn’t fair in love and war. Although some might still doubt that there is any place for war in civilized human society, if there is indeed such a thing as a just war, then contagious biological weapons don’t have a place in it.

Can we end biological weapons?

So, what can we do? It’s one thing to decide that bioweapons are a bad idea, but how can we prevent their development and use? How can we give the BWC its teeth?

One option is to revisit the development of a system of verification. Although it may be impossible to determine with absolute confidence that a state is not developing biological weapons, an imperfect verification protocol will likely still have benefits.

Firstly, without a verification process there isn’t a way to counter allegations like those made by Putin a few weeks ago. Although states could still make these sorts of accusations, having some verification process would reduce the ease with which they can do so. This may help to avoid the false flag tactics that have been used by the Kremlin previously.

Secondly, it can act as a deterrent by making the development of bioweapons more difficult and more costly. It would be much easier to develop a bioweapons program if there was no need to take steps to hide the efforts, and these steps taken to hide the program would also increase its costs.

Finally, it can help to strengthen confidence and decrease suspicion between parties to a greater degree than do the existing CBMs. Increasing confidence is important because if countries believe that other militaries are investing in bioweapons then they might invest more in biodefense research. Unfortunately, as mentioned, most of this research is dual use in nature – it can be used for offense as well as defense. So, more countries investing more in biodefense might paradoxically increase the risk of bioweapons.

Partly for these reasons there is renewed interest in establishing a verification protocol. And there is hope that advances in biotechnology might make it possible to develop a protocol that can provide a greater level of assurance to state parties, while also allowing enough privacy for researchers and industries who were worried about the intellectual property implications of previous verification proposals. Building this requires technical knowledge in this area as well as strategic thinking.

It also seems like there could be a role for careful advocacy to increase the importance states put on the BWC. This may help in efforts to develop agreement on verification, and in increasing the resources available to implement the convention. Four people really is not many to have working on this, especially considering the Chemical Weapons Convention has a staff of 500. However, any advocacy in this space should be done with care, as attention itself can be dual use – although it’s necessary for developing solutions to the problem, attention from the wrong people could also speed up the development of bioweapons.

It’s exciting that some smart people influenced by the ideas of effective altruism are involved in these efforts, and that there is funding available for efforts to work on this. If you find this interesting, then I encourage you to think about how you could work on this problem.

Whether a war can be just might be controversial, but whether bioweapons should be developed and used isn’t. We already have too many ways to bring devastation to humanity and earth. We should be trying really hard to prevent another one.


If you have any feedback on this post or notice any errors, please let me know through this anonymous form. I'm grateful to Garrison Lovely and Brad Davis for helpful edits on earlier drafts of this post.


[1] The description of the history of biological weapons and the BWC in this section and the following section largely comes from two books published in 2006 - Bioterror and Biowarfare: a Beginner’s Guide, by Malcolm Dando, and Deadly Culture: Biological Weapons Since 1945, edited by Mark Wheelis, Lajos Rózsa and Malcolm Dando.

[2] For more on the Soviet bioweapons program see The Soviet Biological Weapons Program: A History by Milton Leitenberg and Raymond A. Zilinskas.

[3] Although, as Luca Righetti points out, at least the BWC has been verified in some ways.

[4] Filippa Lentzos uses this term in the 2013 policy brief, as does Malcolm Dando in Bioweapons and Biowarfare, and John R. Walker in this recent paper.

[5] A few important contributors to this field have been Jeff McMahan (see Killing in War, Michael Walzer (see Just and Unjust Wars) and Helen Frowe.

[6] I guess it sounds cool.

[7] For anyone who was wondering, the Latin bellum, meaning war, is apparently not etymologically related to bellus meaning beautiful (from which bello/bella in Italian/Spanish comes from), but the closeness of the words is thought to explain why the Germanic war became more commonly used. It’s also not related to the bell, which has a Germanic origin.

[8] An additional principle of jus in bello that is sometimes included is mala in se, which refers to weapons that are evil in themselves. However, this leads to the question of what makes a weapon evil in itself. Although I’m sure there is a lot more that could be said about this, it’s been argued that the principles of jus in bello described above cover much of what makes a weapon evil. This makes sense to me.

[9] The US CDC suggests the 1918 pandemic is estimated to have killed at least 50 million people. Wikipedia suggests World War I saw 40 million casualties.