"Yeah, marines need a lot of that." The phrasing is sarcastic, but the tone isn't, and Sarah's smile softens, an easy-to-read microexpression. "Seems like the world might be nicer, but the people invading aren't. I don't know how likely they are to spread out past here, but if there's a real chance of it, this place might get ruined in the process of stopping them."

Sometimes you have to sacrifice a planet. It's awful, but you can't get so focused on one star system you forget the bigger picture.