Why does dr. sasaki become an automaton in the story hiroshima?

In John Hersey's "Hiroshima," Dr. Sasaki becomes an automaton as a coping mechanism in response to the overwhelming trauma and chaos following the atomic bombing. Faced with the immense suffering and devastation, he detaches emotionally and focuses on the immediate task of treating the injured, shutting down his feelings to manage the Horror around him. This transformation reflects the broader human struggle to endure unimaginable circumstances by suppressing emotions and functioning mechanically in the face of disaster.