In this poem, dying for your country (or even fighting for your country) seems a lot less worthwhile than the trumped-up truisms of old patriotic battle cries imply. Strategically drawing his readers through the ghastly reality of life in a battle zone, Owen turns patriotic fervor into a kind of deadly life force. The people at home just can't understand how horrible life on the front actually is. The soldiers in war can't remember why they are fighting. Everyone, it seems, is lost: lost in a fog of war or in the useless ideals that sacrifice youth at the altar of national glory.
"Dulce et Decorum Est" privileges individual well-being (or ending individual suffering) over the collective good.