...I'm the last one to defend Klaus Mikaelson. Which is sad, since I love most of that family. I even like Kol when he's not a possessed douchecanoe.
They're upset. They're scared and stressed. He's threatening a kid. I doubt most of them would ever follow through with those threats. But he needs to be made to understand that indestructable doesn't mean we can't hurt him. He may not die, but we can make his life unpleasant if he hurts people.
I don't like what the demon is doing with James, either. But beneath that is a sixteen year-old kid who's probably really scared. And we can't just let Klaus go killing him because "he can".