Reading V.L. Parrington's epic three-volume study of the Main Currents in American Thought, it is clear that a persistent theme in the work—indeed, a characteristic obsession of Parrington's—is that American farmers and agrarian interests have long been the source of every progressive, popular, democratic, pacifist, humane, and reformist impulse in American life.
John Dos Passos's USA trilogy often reflects the same assumption. When Wilson's war in Europe looms, the characters in Dos Passos's epic often talk as if it were a given that the small farmers of the great Midwestern Plains would be one of the surest political obstacles (alongside industrial workers) to this push for war and profiteering.