Explain Kiowa's obsession with the death of Lavender and Cross' reaction. WHy is this significant?

Lt. Cross reacts to Ted lavender and Kiowa's deaths with exteme feelings of guilt. He was responsible for the lives of his company, and because of their death's he tears up the pictures of Martha (his unrequited love) feeling his preoccupation with her was responsible for his inattentiveness. Death is the only constant in war and men deal with it in different ways.

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