What makes biological weapons so dangerous, and does Russia have them?
The weapons are banned, but the ban is poorly policed

VLADIMIR PUTIN’S forces have committed many atrocities in their invasion of Ukraine. Some fear there is worse to come. America has warned that Mr Putin may be considering the use of biological and chemical weapons. On March 23rd, ahead of a NATO summit, Jens Stoltenberg, the alliance’s secretary-general, said he expected its members to provide “equipment to help Ukraine protect against chemical, biological, radiological and nuclear threats”. The use of chemical weapons would be nothing new for Russia: it has previously used them in attempted assassinations, and the Syrian regime that it backs has used sarin gas. The use of biological weapons, though, would be novel—and potentially more deadly. What is the difference between biological and chemical weapons, and why are the former so troubling?

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