War is everywhere in the Aeneid. The Trojan War begins Aeneas's journey by forcing him from Troy, and war concludes his journey on the fields of Italy. The characters constantly contend with the possibility of violence, giving gifts and forming alliances to try to avert it, or proving their bravery by rushing into it. And these wars are never purely tactical, fought just to gain land or power or wealth. Instead, the wars are often the results of personal, petty things, like insults or grudges. The Trojan War begins because of three goddesses' squabble about who's the most beautiful. The war in Italy begins because Turnus gets mad that a stranger is marrying the girl he likes, with Juno fanning the flames for a whole host imagined slights. These frivolous-seeming beginnings lead to warfare that offers the chance for glory, but which Virgil also regularly depicts as brutal and senseless, separating mothers from sons and sons from fathers.
Yet in Anchises comment in the Underworld that Rome will have the unique ability to spare the conquered (in extreme contrast to what the Greeks did to the defeated Trojans), the Aeneid suggests that the Romans, through Aeneas, will bring something new to war—that they will wage war in order to create peace.