The Heart Is a Lonely Hunter, true, but it's also a bit of a violent one as well. Violence closely impacts every character, and even somewhat likeable folks are prone to violent actions, or at the very least violent thoughts. This is the American South in the Jim Crow era, after all, and communities were charged with racist violence. But not all violence in this book is related to race. Some of it is domestic, some of it is accidental, and all of it has wide reaching impact. The grief and emotional turmoil that follows a violent incident unite these characters, even as those emotional responses often tear them apart and further isolate them.
Mick and Blount are the novel's most violent characters, and their violent tendencies are the only thing that links the two together.
Copeland may talk about peace, but he is the most violent character in the novel.