In the title essay of his 1980 collection, Pietas: Selected Studies in Roman Religion , the Dutch classicist Hendrik Wagenvoort traces the Roman notion that their success was a result of their piety back to the Roman conquest of Greece. How, the Greeks wondered, could the culturally inferior Romans overwhelm Hellas? Some Greek thinkers said that Rome was simply more consistent with the Hobbesian principle of international order: They won because they acted out of pure, brute self-interest.

The charge stung, and Roman writers looked to justify Rome’s existence. The Roman answer was pietas ; the Romans convinced themselves that “Rome’s greatness and world conquest as a fruit of piety” (17). Cicero was its belated defender:

“in the last years of his life Cicero made a surprising discovery which seemed to provide him with a perfectly satisfactory solution. What if every state had its destiny! What if the deity had called Rome to found a world empire! What if the Roman conquests had not come about from a ruthless urge to further the Romans’ own interests, but from faith in the divine calling, from that sense of duty which silences every human voice before the voice of the deity, in brief—from pietas !” (14-15).

This conflict between self-interest and piety is the key conflict in the famous encounter between Aeneas and Dido at the opening of the Aeneid: “The main point . . . is that, in this tragic conflict, we see depicted a clash between self-interest and the divine calling. Aeneas is the hero because he sacrifices his own desires, his own love, for the formidable task of seeking a new land for the fugitives from Troy for whom a glorious future lay in wait . . . . [Dido] therefore bases her lament on Aeneas’ piety, which she cannot understand in a more elevated sense. And after that, as she flings her curses after him in her powerless rage, she cries prophetically that an avenger of Carthaginian blood will arise to complete the deserved punishment in a bitter war against Aeneas’ descendants.”

Wagemvoort offers a historical allegory on Dido’s curse: “What does this mean ? It means that the war with Hannibal and the Punic wars in general were a result of Aeneas’ piety, or, in other words, deprived of poetic symbolism, that they were a necessary consequence of Rome’s obedience to the divine calling” (16-17).