Walk in Hell by Harry Turtledove

The Great War: Walk in Hell is the second installment of Harry Turtledove’s "The Great War" series, covering, more or less, the second year-and-a-half of the war, along with the continuation of the revolt of the Confederacy’s Black socialists and the United States’ Mormons. Throughout the majority of the novel, the United States manages to retain the position of dominance it carved for itself in the first book, although the novel ends with the war no closer to an end and the outcome in just as much doubt as it was at the beginning of the book.