Why are we doing this?" Caine asked him. "You know damned well why we're doing this. Because it's a fight. It may be THE fight. I may be the final fight. And what else are we good at, you and me? What are we going to do if we ever get out there anyway?

But then had come the voice that said, "Come on, you little freak, wherever the hell you are,
whatever the hell you are, let’s get this done with.

She’s stronger than you are, Sam. It’s like fighting yourself and Caine and Jack and Dekka, all at once.”
“Yeah.”
“Talk to Astrid about it.”
“I already talked to Astrid.”
“And she’s okay with a suicide mission? Because I’m not. You go out there, go to win, huh? Don’t go out there thinking you’re doing us a favor by getting killed.”
Sam sighed. “It’s the endgame, my friend.”
“Sam . . .,” Edilio began, but that was all he had, that one word, that one-word plea for a different solution.
“Take care of Astrid for me. Try to keep her safe and don’t let her follow me.

Fighting evil with evil doesn't diminish it; rather, it increases the evil.

She saw the inherent evil in segregation and she had the courage to fight it in its common place, a seat on a bus,

Good courage in a bad affair is half of the evil overcome.