What are the motifs in Cavalry Crossing a Ford by Walt Whitman?

Nature The fact that this is a cavalry regiment, composed of both men and horses, helps the poem emphasize the theme of nature. In one sense, the poem is a study of the interplay between nature and humankind. The military unit is a powerful symbol of humanity because it represents the extremes of human thought: the basic carnal blood thirst that drives violence, along with complex strategic logic.