There are some members of that race who are good. [Well...one Magog who is good. He's never seen or heard of more than that one. But that one opens up the possibility that there could be more.]

But we are trying to destroy the invading force. [Did destroy it. But at a cost that's unacceptable. So Dylan's here to earn a redo from the Admiral.] It's easier said than done, since they number in the trillions.