Purim is, among other things, a festival of blame. We gather as a community to publicly name and boo the bad guy.
I have always hated this aspect of Purim; it feels wrong to revel in the evil of another human being. As a kid, I would cover my ears and shift uncomfortably in my seat. As an adult, I try not to focus on the final chapters where we read about the violent vengeance wrought by the hanging of Haman’s sons.
But the Megillah is unfurled each year for good reason: it’s a warning that evil really does exist in the world, and that we as Jews have the power to stop it in its tracks.