It isn't about blame. [At least he hopes not. He tries, anyway, though he would be lying to say the conversation never veered in that direction in the middle of an impassioned plea.]

Believe me, I know the depths to which mankind can plummet. What they can do. ["They." Like it's separate. An innocuous little thing that could be understood in many ways.] But you can help them see something better. Do better. Be better.