I really like this passage from Julia Turner’s Slate piece on Harry Potter and the Half-Blood Prince:
[J.K. Rowling is] not using Harry to make points about terrorism. She’s using terrorism to make points about Harry. Rowling culls the scariest elements of modern life and uses them as a kind of shorthand, a quick way to instill fear.
I hadn’t thought about it in that exact way before, but I think it describes the situation perfectly. I think the thing that has most intrigued me about the series as it’s gone on is the way the mechanics of Voldemort and his minions the Death Eaters have slowly transformed from nebulous fantasy-stock Dark Lordisms to real down-and-dirty hands-on torture and, especially, murder. As compelling as Tolkien’s Sauron is, there’s something impersonal in his grand-scale plottings and massive armies; Voldemort, on the other hand, has his cult members break into houses, schools, and government offices and execute people. I think Rowling likely went this route because unlike most fantasy villains, Voldemort does not control territory, not even a castle or fortress. Quite like terrorist cells or organized crime gangs, he and his followers are everywhere and nowhere, and when they strike, it’s with individuated strikes against civilians. It’s wetwork.