Swatting flies, I'm always amazed that (despite their well-known multiple eyes) they let me get within swatting range without taking flight. I find I can get into swatting stance over them, and they take no notice. Even when I raise the fly-swatter above them, they blithely ignore me. It's advantageous to me that they don't take alarm, or try to flee, until the last instant before destruction: I'm able to kill most of those I target.
If I were satan, I would look at today's American Christians the same way.