[Shepard's about to say "yes," since they need to be killing these idiots yesterday, but remembers she doesn't have that authority anymore. She can't shield Garrus from the potential consequences of using lethal force by invoking command authority. Instead she just sighs.]

Not my call to make, but I can tell you I'm not pulling any punches from now on. This has been war since the Apokalips mission went south, and I've been waiting for the locals to realize it.