Monsters generally represent a fear that society doesn’t want to face directly at the time. Take the widely accepted notion that Count Dracula represented unexpressed libido to the repressed Victorians. I also think class issues are being played out, since Dracula is a Count after all. Werewolves are said to represent a body-fear at the onslaught of puberty. And I think also male aggression. Frankenstein I think represents more a fear of surgery and medicine than the traditional gloss: a fear of the extending powers of science. And zombies in the 50’s represented the cold war, we are told, while now they seem to represent the post-apocalypse itself, not the cause.