It is important to remember the context of this excellent short story. The author chose to set this tale in the aftermath of the bombing of London in World War II, and in particular to explore the impact of the bombing and war on the younger generation, who would have known no other reality except for war. The various characters we meet in the form of Blackie and T. are presented as teenagers who have become curiously detached from "normal" feelings and emotions. This is of course exemplified in the character of T., who says, when he is burning Old Misery's money:
"All this hate and love," he said, "it's soft, it's hooey. There's only one thing, Blackie," and he looked around the room crowded with the unfamiliar shadows of half things, broken things, former things.
This quote shows just how detached T. has become from "normal" human emotions. He is presented as a character who has internalised the external war and violence into his own psyche, and as a result is not able to experience emotions such as "hate and love" as any normal child would. The message of this story is that the innocence of humans is something that can very easily be tainted or lost, with horrific consequences.