Cortana is the last person with standing to criticize someone for never changing clothes.

"There'll always be another war." She's a very flexible AI. She can easily postulate a universe without violent conflict. It doesn't happen to be the one she's from. "Probably not with the Covenant, though."

She shrugs at Locus and spreads her hands with a wry half smile. "Big galaxy. I'm sure we'll find someone else who hates us."