In the face of a determined human attack, almost all animals are effectively "helpless". When I decide that a particular groundhog (for example) has come to the end of its run on this Earth, there's very little it can do to change matters.
Perhaps better to say that "purposefully harming harmless animals etc."
Come now; you don’t really think she was talking about pests, do you?
She is correct; many murderers start out by killing cats and dogs.