Wilfred Owen was an English soldier who wrote various poems surrounding World War I, and is regarded as one of the leading poets of the era. Among others, he used "Dulce et Decorum Est" (an attack on the commonly-used quote's support of death in war) and "Anthem for Doomed Youth" (a lament for slain young soldiers) to evoke emotion towards war as a whole. To achieve this, symbols and language techniques are used that help the reader understand the tragedy of war.
A key example of the techniques used is the opening line in Anthem for Doomed Youth: "What passing-bells for those who die as cattle?" This combines two techniques. Near the end, he compares the soldiers of war with cattle. Owen realizes that people normally think of cattle as one-purpose animals that are used as tools only, implying that the soldiers have no purpose other than dying, they are not cared about. This is enhanced with a rhetorical question. The rhetorical question is used to let the reader realize themself the tragedy of war (instead of forcing it). The purpose of this was to create empathy; because we ask ourselves the question, we are put into the boots of the soldiers. We ourselves would not like to be one-purpose tools, and Owen helps the reader realize this by generating empathy. Anthem for Doomed Youth follows a two-sided approach, with the first paragraph following a brutal approach, and the second following a mournful approach. "What candles may be held to speed them all?" contrasts the first line well. It holds the same idea, but with a mournful approach instead of brutal. Once again he asks a rhetorical question, but this time asks what candles may be held to "speed them all". Speed means to expedite; in other words, send to the afterlife properly (implied by the church-like wording).
Unlike the scarce but strongly intentful techniques in Anthem for Doomed Youth, Dulce et Decorum Est uses an array of assorted techniques. A simile is used in the starting line; "Bent double, like old beggars under sacks". The second section, "like old beggars under sacks", does well in describing the soldiers. We think of beggars as scruffy, worn out and lifeless, and "under sacks" aids in the hunching description of "bent double". Owen's intent was likely to completely warp our opinion of soldiers, we think of them as noble and proud, but he clearly equals them with what we would consider the worst-off in society. The ambiguousness in the previous line was removed in the second, with "we cursed through sludge". This clearly infers the poem is describing an army, and that the writer is describing his experience. The intent in this was both the aforementioned reason and to expand the power of the forthcoming lines, they would be trivial to someone unaware soldiers are being described. The further lines make use of other minor techniques, such as personification, metaphors and alliteration. Their use builds up with emotive language, which develops into a strong part of the poem. A gas attack starts, and the second paragraph starts with "An ecstasy of fumbling". This emotive language develops over time, when a friend of Owen's is killed by the gas attacks. He then brings the person into the picture - "If [...] you too could [observe]" - and follows with deeply emotive language - "the white eyes writhing in his face, his hanging face, like a devil's sick of sin". The emotive language was used to make the reader come as close as Owen could to the event itself. "Writhing" describes a violent squirm, and "devil's sick of sin" affiliates the events with the devil, which would be held as deeply evil in that time. The same ideas are reiterated to perhaps build up the emotive language to its pinnacle; it re-introduces the reader - "If you could hear" - and follows - "the blood come gargling from the froth-corrupted lungs, obscene as cancer". This uses a multitude of emotive words, and clearly depicts an extreme feeling of pain, using words like "gargling, corrupted, obscene", and comparing it to cancer. This whole buildup of emotive language follows with "you would not tell with such high zest to children ardent for some desperate glory, the old lie: Dulce Et Decorum Est Pro Patria Mori". That phrase is one describing war as sweet and fitting, which was told to soldiers entering war. Owen has made it remarkably obvious this is not true, with the buildup of emotion describing pain, violence and death.
Conclusively, these techniques and symbols show Owen's obvious intent to attack the glorified view of war. In "Anthem for Doomed Youth", this was not obvious, but was very persuasive when the reader thought about it. Oppositely, "Dulce Et Decorum Est" makes it very obvious, with strong emotive language and clear intent. It could be said Owen was trying to talk to a wider audience, and because of this, aiming to make a difference, instead of ranting and whining. It's unfortunate that these attempts were futile, with the aftermath being larger and deadlier wars. I couldn't think of a nice final sentence, so here's one that degenerates the whole essay and completely breaks the narrative technique. Cock is great.