Answer:
The evidence for Paul's reaction is:
1. People have no idea what happens in the war.
2. People worry about super-nice things while the war is going on.
3. He matured a lot and hard, while in military training and on the battlefield.
Step-by-step explanation:
Paul used to identify with the people of his homeland, since he lives with them and shared very similar experiences, however, when he was called up for military service and taken to the battlefield he found himself in a very difficult reality to deal with. He had to mature very, very quickly to maintain his sanity in such an inhospitable environment. This caused him to lose all connection with the people of his homeland and to no longer be able to see them with importance, because they seemed superfluous.