Calmatives agents are in theory an attractive approach not only for national security purposes but also for domestic policing. However, the time lag between the release of a substance and its effect on targeted individuals makes currently available opiates such as fentanyl poor candidates for such uses. It is not well understood, for instance, why the group holding the Moscow Theater hostages did not react when it became apparent that something was going on in the confines of the building, but perhaps they were so overcome with exhaustion that they did not register events quickly enough. Whatever the explanation, there is no assurance that future hostage-takers bent on suicide could be managed in this way. Governments will need to develop a faster acting agent before using calmatives in this way is an attractive option. Also, the open-air release of an agent is unlikely to be effective due to the dispersal of the aerosol, limiting the situations in which a calmative can be an effective non-lethal weapon.
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