“Dulce Et Decorum Est” consists of four stanzas of uneven length. Yet despite being broken into four sections on the page, the overall poem is better understood as having a two-part structure that moves from the past to the present. The poem’s opening section involves the first two stanzas (lines 1–14), where the speaker recounts his past experience of the horrors of front-line battle. This section opens already in the middle of the action. Before setting the scene or situating the reader, the speaker drops us in among his fellow soldiers as they trudge through the muck, exhausted. The drudgery of this march is interrupted in the second stanza, when a canister of poison gas lands among the troops and sends them into a chaotic rush to don their protective masks. All but one of the men in the unit puts on their mask in time, and they are forced to watch as their unlucky comrade chokes to death on the gas, seeming to drown in “a green sea” of smoke.

The poem’s second section opens with the short third stanza, which consists of only two lines (15–16):

In all my dreams before my helpless sight,
He plunges at me, guttering, choking, drowning.

Though these lines remain focused on the dying soldier, they nonetheless signal a shift in time, from the past to the present. The image of the dying soldier has lingered with the speaker long after the scene he has just described, and it continues to haunt him in his dreams. The traumatic nature of this memory leads the speaker to the fourth and final stanza, where he turns to address those of his contemporaries who uncritically celebrate war. He claims that if they had first-hand experience of the brutality of battle, then they wouldn’t dare repeat old-fashioned pieties about the honor and glory of war. The poem’s second section therefore sets forth a powerful political argument, rejecting a long tradition that idealizes the act of dying for one’s country.

One notable feature of the poem’s structure is that each of its two halves has fourteen lines. This fact, when considered in relation to Owen’s use of iambic pentameter and an ABAB rhyme scheme, faintly suggests the sonnet form. The only formal element that’s missing from the traditional sonnet form is the use of a final rhyming couplet. Even without this formal element, however, the poem still evokes the sonnet in a way that may be read as ironic. In the history of English verse, the sonnet has long been considered a highly elevated poetic form that showcases formal elegance as well as linguistic compression. Yet Owen’s poem is far from elegant in the way it dwells on a series of horrific and even gory images. Filling a sonnet with reflections on the brutality of war arguably violates the form in a way that subtly amplifies the poem’s overt antiwar message.