Towards the end of his life, Carter became more addicted to the white pipe, as he wasn't able to cope with his memories about the cruelties of war he had seen, the death of  a friend and the moral questions others and he himself asked him about the way he had treated the Sudanese girl he had taken a picture of.  
Was he wrong to leave the girl to die and be eaten by the vulture or should he as a human being have intervened? apparently the girl had enough strength to walk away from the vulture, but  her ultimate fate was unknown.