Why is it so difficult for Bruno and Gretel to understand the true nature of Auschwitz?

The theme of innocence is tied to that of Bruno's childlike misunderstanding of the tragedy through which he is living. His innocence prevents him from understanding, in the last chapters, the fate he is about to experience in the gas chamber. As he is marched along with the other prisoners, "he wanted to whisper to them that everything was all right, that Father was the Commandant, and if this was the kind of thing that he wanted the people to do then it must be all right" (210). Bruno is, of course, completely wrong: this is the sort of thing Father wants the Jews to do, but there is nothing "all right" about it. The very character in whom Bruno has faith is the one who is bringing about the deaths of so many, his own son included.

Gretel might be seen in the same way, although throughout the story we see a little girl growing up and the act of indoctrination taking hold. When we first meet her, she is clearly a child, though a few years older than Bruno. She spends most of her time arranging her dolls and has brought the entire collection from Berlin with her. Significantly, she is the one who tells Bruno that the name of their new home is "Out-With." This misnaming of the specific location marks Gretel as a child at this point, in contrast to the teenager she will grow into by the end of the story. Finally, Gretel replaces her collection of dolls with maps of Europe given to her by Father, which she updates using the newspapers each day as she reads about developments in the war. Her transition out of childhood naivete is represented clearly in her correction of Bruno's usage of "Out-With" in place for "Auschwitz." It was she who first told him the name of the place, but now she corrects him. Her understanding of the situation is still simplistic and lacks understanding: she has accepted what her Father and Herr Liszt have taught her without much critical thinking.

They are comepletley stupid idiots and Bruno gets himself killed.

TWAT

I think this was very helpful :T but u gotta admit bruno didnt understand anything that was happening