The novel takes a consistently anti-war position. In the text, war is dehumanizing, barbaric, random, and vicious. The First World War is different, however, from conflicts that have come before, due to its scope and technological advancements. Many characters enter into the military with expectations of how the conflict will develop based on the comparatively “organized” Napoleonic era, believing that the war will be over by Christmas. Levitt, for example, reads old texts on the nature of war, only to find that all of the old writings are obsolete and inadequate, unable to provide an explanation or frame of reference for the situation Robert and the others find themselves in. War is hell, the novel suggests, but this new war is even more hellish than before.

The effect of war is not limited to men. In the text, men are the vicious enactors of the barbarism of war and then have a terrifying effect on nature. Rodwell countermeasures this, as he collects the stricken animals and tries to save them. Only his toad, an arguably ugly creature who thrives in swamps, survives a gas attack. The entire biosphere around the battlefield is destroyed and all but the animals most attuned to filth suffer due to man’s actions.