Examine the destruction caused during the war in The Boy in the Striped Pajamas.

In The Boy in the Striped Pajamas, Bruno is the our guide to the destructive capacity of the war.
As the focus for the narrative, Bruno interprets the destruction of the war for us, the reader.  He sees the war as an inconvenience because it has caused him to leave his home, his friends, and enter a world unfamiliar to him. Bruno does not see the people in "Out-With" as anything more than the people in "the striped pajamas." Yet, in these impressions, we get a glimpse of the wide level of war's destruction.  For example, when Bruno sees the large number of people boarding the "other" train to Auschwitz, we grasp the depth of the war's extermination. All of "those" people are intended to be killed. What Bruno see, we understand in a very horrific realization.  As Bruno moves us to a very sad threshold of revelation, we become aware that if Bruno sees it, it also exists on a larger level.  
Through his personal interactions with people in "Out-With," Bruno is able to show us further evidence of the war's destruction.  This is seen when Bruno learns that Pavel had a "different life" as a doctor before being imprisoned in the camp. The war destroyed Pavel's former life and replaced it with this one. Bruno sees the Nazi destruction of their prisoners in his perceptions of Shmuel. Bruno sees Shmuel's thin hands and his eyes swollen into his head.  His impressions help us understand the brutality of the Nazis.  We realize that the Nazis starved and humiliated millions like Shmuel.  When Bruno sees the scars on Shmuel after he has been beaten by Kotler, it is another instant of Nazi destruction. In these personal accounts, Bruno affords us a broader perspective about the war.
When Bruno and Shmuel are herded into the gas chamber, the destructive capacity of the war is fully displayed. When both boys are swept with the mass of people into the gas chamber, followed by its darkness, as well as its fear, we grasp the full level of the destruction that millions of Nazi prisoners experienced.  Bruno's final experience has put us in the most painful part of the Holocaust. The gas chamber reminds us of the Nazi's cruel capacity for destruction.  As Bruno perceives this annihilation of millions of people, so do we.  In this way, his personalized understanding enables us to gain a wider view of the war's destruction.