They tend to write about it because they have probably experienced it themselves or have felt the pain from others
It would be my pleasure to help you out on this answer. Would it be alright if you would take a photo of the text your are going to right about?
Answer:
When Bruno's father raised his hand, it clearly showed his sign of authority, and that he had a high ranking in the "Fury's' army. This tells us that Bruno doesn't know what is happening just a little bit beyond the fence, and he is blindly following his father.
Hope this helps!
