3 ideas
The narrator reports what he sees, hears, eats, and is ordered to do in short declarative sentences and offers no commentary on whether any of it is right. Because the text refuses to interpret, the reader must supply the moral conclusion, and a conclusion the reader reaches unaided feels like evidence rather than persuasion. Flat affect works as a rhetorical strategy precisely because it looks like the absence of one.
For the man in the ranks, a war is not a campaign with objectives. It is a sequence of marches, digging, hunger, weather, rumor, and sudden fire, and he rarely knows where he is or why. Strategy exists only at levels he cannot see, so his real experience consists of fragments and endurance, not narrative. Accounts that give the war a coherent arc are therefore written from a vantage point no fighting soldier occupied.
The sergeant stands between officers who issue orders and men who carry them out, and his authority with the men rests on competence and on shared hardship, not on rank. When higher command repeatedly spends lives to no visible purpose, the middle layer stops passing legitimacy downward, and discipline empties out from the center before it breaks openly. The book's arc follows this process until the army dissolves in the collapse of 1918.