Few allegations are as damaging and difficult to counter as accusing somebody of deliberately spreading a disease. Unfortunately, global events have led to a distinct uptick in such accusations. Earlier this week, the White House warned that Russia could be planning a chemical attack in Ukraine. And Russia’s Foreign Ministry recently accused the US of having established secret bioweapons laboratories in the country. It’s an unfortunate, but perhaps not surprising, escalation of the conflict.

Spurious allegations of biological warfare and lab leaks are not particular to the Ukraine war, nor are they novel. Instead, they regularly surface during moments of crisis and uncertainty, such as the Korean War or ahead of the 2003 Iraq invasion. These events and others from the past hundred years have shown that we would do well to be wary of underlying agendas among those engaging in finger-pointing. We should also not underestimate the long-term damage and unexpected afterlife these allegations can have.

One of the earliest biowarfare scares took place a century ago, in 1920, when news hit of an alleged plot by the Irish Republican Army (IRA) to disseminate typhoid and glanders among British troops in Dublin. Similar to current biowarfare allegations, the public discourse surrounding the alleged “typhoid plot” highlights the importance of geopolitical interests and targeted (dis)information campaigns in shaping interpretations of disease outbreaks and threats.

Between 1914 and 1918, the first world war had inaugurated a new era of industrialized mass killing—including the weaponization of chemical substances like mustard gas and biological agents. In 1915, Germany initiated attempts to sabotage Allied troops by spreading anthrax and glanders among horses. While the scale and strategic value of these early attacks were limited, their effect on the imagination of military planners and civilians was significant.

After 1918, bacteriological weapons were simultaneously perceived as a great taboo that civilized nations should not engage with and an emerging field of warfare that required investment in offensive and defensive capabilities. The relative ease with which pathogens could be cultured also meant that nongovernmental actors such as anti-colonial movements were now theoretically capable of developing lethal weaponry.

It was in this context that news of the alleged IRA typhoid plot broke on November 18, 1920. In Ireland, the British government had been engaged in a full-blown anti-insurgency campaign since 1919. Allegations of IRA bioterrorism came at a critical moment when British planners were deliberating whether to escalate anti-insurgency measures.

During a raid, British troops had discovered an alarming letter anonymously written to the IRA’s chief of staff, Richard Mulcahy. In it, an anonymous source discussed spreading typhoid via milk among British troops stationed in Dublin and infecting horses with glanders. With typhoid, the writer knew of “no other ordinary disease which could spread amongst the troops but ensure the safety of the rest of the population.” General Ormonde Winter, head of British intelligence at Dublin Castle, had couriered the letter to Westminster as a matter of urgency.

News of the alleged plot caused furor. Focusing on the planned weaponization of typhoid, which was a heavily stigmatized disease of filth, British and Commonwealth journalists immediately drew parallels between the IRA and German sabotage, legitimizing a potential intensification of Britain's anti-insurgency campaign. British officials amplified public outrage by highlighting the nefarious nature of weaponizing microbes. They also used the plot to challenge the moral legitimacy of the republican cause with Prime Minister David Lloyd George, who had already described the IRA as a gang of murderers, allegedly refusing to receive a deputation from the Irish peace conference.

Meanwhile, the alleged typhoid plot was ridiculed by nationalist Irish MPs. Well aware of the reputational damage the plot could cause, they accused the British government of “black propaganda” against the Irish freedom movement, and of “concocting” it in Dublin Castle. An incredulous Arthur Griffith, president of the Irish republican political party Sinn Fein, labeled the affair as a “lie so ridiculous that it is almost impossible to believe that the man who denied the burnings of towns in Ireland by his forces would venture to state it.”

Similar to the recent Russian biowarfare allegations and Western intelligence reports on planned Russian chemical attacks, the 1920 allegations did little to change the opinions of people who had already decided to support or oppose Irish independence. Instead, their importance consisted in sowing doubt and polarizing broader international audiences—a cultural impact that quickly outweighed any military aims biowarfare could have achieved. Morally, portraying the enemy as ready to commit the most depraved crimes helped desensitize combatants and added further fuel to a fast escalating cycle of entirely conventional violence.

In the case of the Irish conflict, such an escalation took place within three days of the typhoid plot’s announcement. On November 21, 1920, IRA assassins killed 14 alleged British intelligence officials across Dublin; British troops retaliated by killing 14 spectators at a Gaelic football match and murdering three prisoners in Dublin Castle. The mutual horror caused by these killings not only overshadowed speculation about the typhoid plot, but also helped trigger a gradual shift toward compromise on both sides, which resulted in the truce of July 1921.

While history holds no clear lessons for the present, comparing the events of 1920 to 2022 nonetheless reveals eerie parallels. Once again, two sides are locked in an escalating conflict. With Russian hopes for rapid advances quashed and no clear military victory in sight, biowarfare allegations signal growing frustration on the part of the Kremlin. Whether Russia is using the allegations to prepare the ground for chemical attacks of its own—as alleged by Western intelligence—remains to be seen. What is clear, however, is that, just as in 1920,  this escalation in the war of words will not only further desensitize combatants and their domestic audiences, but also narrow remaining hopes for compromise. A barbarous enemy is not one you can negotiate or coexist with.

Broadcast to millions of viewers, Russian biowarfare allegations will likely also outlive the current conflict. Although Bloody Sunday quickly overshadowed the Irish typhoid plot, named individuals like Richard Mulcahy continued to be questioned for decades, and historians are still investigating it. Containing the seeds of distrust sown in 2022 will take far longer.

WIRED Opinion publishes articles by outside contributors representing a wide range of viewpoints. Read more opinions here, and see our submission guidelines here. Submit an op-ed at opinion@hyzs518.com.

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