Wow, great replies everyone. To each his own... but for us, we try to work with nature as much as possible. That said, I wouldn't hesitate to kill a predator going after our hens (or any other of our animals, children, etc) For the time being, I will be packin' when I'm out with the hens.
Citrusdreams-- yes, I am thinking about another dog. We have an Aussie right now, and she is great with the chickens. She is especially good at keeping hawks at bay... unfortunately though, I can't get her to be out where the chickens are when I'm inside. She's my shadow and when I'm inside, she's glued to the porch until I come out again. From that vantage point, she can see hawks and will race out to scare them away, but not ground predators. I also worry about her not being evenly matched if more than one coyote came around. As another posted mentioned, the coyotes here have interbred with wolves and are quite large. The one we saw was as big as my Aussie. So...my girl needs back up! I will start exploring other options.
In the meantime, at least I know my coop is secure. 100%. It was once a tack room in the newer barn, cement floor and walls, with a steel door and heavy duty windows that we've covered with hardware cloth. In there at night, I know they're safe. The run I'm worried about though. During the day it has offered adequate protection-- but now, I think a determined coyote would find a way in. I'll be working on that this week as well.
Thank you again everyone!
PS. LOL about the rain, TipsyDog! I can believe it!