Michael Morpurgo’s Private Peaceful shows that conflict brings out the worst in people.

Conflict brings about abuse and bullying. Throughout the book, Tommo deals with numerous instances of bullying: people in power using their influence in pointlessly cruel and petty ways. Grandma Wolfe's treatment of the children is cruel; she insults and hits them constantly. The Colonel is an incompetent and cruel man, constantly threatening the Peaceful family with eviction unless they follow his whims. Later on, in the army, Sergeant Hanley targets both Tommo and Charlie as objects of his bullying, and when he realizes that Tommo is underage, he targets him all the more. The book also deals with the problem of standing up to bullies, which is nearly impossible as the boys are powerless in each situation and they would find themselves punished all the more terribly if they were to try to stand up for themselves. Notably, Charlie frequently stands up to instances of bullying (such as in Mr. Munning's classroom and in the army), and he eventually dies because of this after he is accused of desertion.