Why dehumanize the enemy? In the political realm it's not just cruelty, it's strategy for marginalizing individuals or groups. Animals aren't smart or rational enough to have considered opinions; they don't deserve the dignity of conversation. You don't have to justify why you won't listen to an animal. It's a waste of time, and dangerous, too. You don't have to justify the fact that animals don't have rights. And, more darkly, you don't have to justify killing animals; they aren't human. That has happened now and then in human history. And it begins with treating people like dangerous, stupid, or dirty animals.
Here I want to talk about how our culture starts very young, in teaching children to dehumanize others. It flies under the radar too often, and here I want to start simply by making people aware of the problem. Notice how a famous children's author cues her readers which characters they are supposed to hate by referring to the characters in sub-human terms -- that, is, by dehumanizing them. The animal comments are often even less subtle than having them perform animal actions like slither or snarl or waddle.
Some early introductions from book 2 of a series:
- Aunt Petunia was horse-faced and bony.
- Dudley was blond, pink, and porky.
- Uncle Vernon sat back down, breathing like a winded rhinoceros ...
From book 3:
- Aunt Petunia, who was bony and horse-faced
- Uncle Vernon snarled
- Dudley came waddling down the hall
From book 4:
- her lips pursed over her horse-like teeth
- ."You," he barked at Harry. [Vernon again]
- Dudley was crammed into an armchair, his porky hands beneath him
In book 5, I expect we could look up the introductions of Harry's relatives again, though the new villain of the book might add some insight as to how an author dehumanizes a character, and does it in a way calculated to cause revulsion:
He thought she looked just like a large, pale toad. She was rather squat, with a broad, flabby face, as little neck as Uncle Vernon, and a very wide, slack mouth. Her eyes were large, round, and slightly bulging. Even the little black velvet bow perched on top of her short curly hair put him in mind of a large fly she was about to catch on a long sticky tongue.The character of Dolores Umbridge is almost entirely hate-bait, one of the characters introduced in order for the audience to despise them, and to be glad when something bad happens to them. Even Voldemort is given a more sympathetic backstory than Vernon Dursley or Dolores Umbridge.
An author can tempt -- or manipulate -- hatred from her audience. One of the standard tools for doing that is to dehumanize a character. And of course it's just fiction. That doesn't make it one bit smarter to accept hatred as part of how we react to people.