Especially people that look the other way when their cats devastate wildlife..... Domestic cats if allowed to be outside can maintaine their hunting instincts and do more damage than some people might think.... I watched her one time make a b-line at a stray cat standing next to my coop and tear the crap out of it like she was protecting the flock.... but I never thought my cat would play a protective role, ... Never rule out domestic cats, some of them can be pretty nasty.
That's pretty cool about your cat protecting your flock. Sounds like a pretty dominant aggressive cat.