There is no precipice. We have to understand these people will keep pushing as long as they keep getting away with it. Whatever line in the sand we might draw and say "there's no way they'd do it." given enough time and enough enablers, someone will try it. We've seen it before. Read the history of the Soviet Union, for example during the defense of Stalingrad. Times were so desperate, there was really nothing the Soviet government wouldn't have done, and the German government was in the same place. We saw mass rapes, literal executions of prisoners of war and even civilians. Any manner of human cruelty happened.

We're still very, very comfortable. These people can and will burn the world to ashes just so they can call themselves king of whatever's left smoldering.