Final answer:
Vonnegut tracks down Bernard O'Hare in 'Slaughterhouse-Five' to explore the impact of the Vietnam War and delve into themes of trauma and the futility of war.
Step-by-step explanation:
Vonnegut tracks down Bernard O'Hare in the context of the Vietnam War. This historical event plays a significant role in Vonnegut's novel, 'Slaughterhouse-Five'. By incorporating O'Hare into the narrative, Vonnegut highlights the impact of the war on individuals and explores themes of trauma, memory, and the futility of war.