Sergeant Major Morris was such good friends with the Whites. But if he really was, why would he hand then such a curse? It says in the story that he was drunk, but he wasn’t obviously intoxicated. Alcohol may have affected him, but I think he probably planned to see them before he drank; most people don’t visit a friend before calling and planning – and even if he is one of those lazy people, He’d still be polite - because as a soldier, you have to have discipline and respect. So he obviously did it for some other reason. The reason is left unknown from the author.
No obvious hatred or conflict has occurred, so I don’t think it was for revenge – if someone did want revenge, he would go straight