This was the Christmas song of 1985, with a message for peace. It came out a little before Nikita, from the same album. I never realised, these songs both came out on the nineteenth studio album of the singer, and it was basically the end of his long career.
There might also be a link to the novel of the same name by Anne Rice. It bears the same name, but also both Elton John and his writer Bernie Taupin were fans of her. I don’t know that book, but I don’t see the link between the anti war lyrics of this song and the vampires of Anne Rice.