As a sixty-something guy who has had a dog in my family for my entire life, I know well the deep emotional bonds we can make with our "canine family members." After nearly 40 years of marriage and with our human children living their own lives as responsible adults, we have an even deeper bond with our current dogs (both rescue mutts) who feel more like surrogate children than pets.
I have also been a firearms enthusiast and competitive shooter for over 35 years. I take my skills and responsibilities very seriously, from the safe handling and storage of firearms to being able and ready to defend myself and my family with deadly force should such an unfortunate circumstance ever present itself. These two passions co-exist in harmony, but I can certainly envision unexpected confrontations that would require absolute objectivity and clarity of thought to avoid a greater tragedy.
Just as situational awareness plays a huge role in personal protection, so it does in dog ownership. Simply stated, in most circumstances deadly force can be used against dogs with legal impunity. Here is a typical example that occurred in NH but is common news just about everywhere.
It is for this reason we must not only exercise extreme "SA" with our dogs but also do our best at all times and all places to anticipate and avoid situations that could lead to tragic unintended consequences. Though there may not be any legal repercussions, the emotional and social costs of shooting someone's pet should not be underestimated. This is especially true for LE when something like this happens. As Americans we have 4th Amendment expectations of being safe and secure in our homes (and on our property) from governmental intrusion. Luckily, there are now training programs for LEO that will help avoid these unnecessary killings and the considerable political/social fallout that is generated by them.
For civilians who carry for self-defense, the old adage just because you can doesn't mean your should applies to the use of deadly force in encounters with dogs, especially so in cases where the presence of dogs is expected (like on someone else's property). If encounters with unattended canines in public areas are a normal occurrence in your life, carrying something like pepper spray might be a better and far less risky first line of defense. At the very least, learn to speak dog.
Dog owners need to "own up" and be responsible as well - allowing your dog(s) outdoors unattended is an invitation to disaster. If your dog "bites" a child (in quotation marks because playful, non-aggressive mouthing can be construed as a bite), you could face civil liability and the emotional stress of having your dog put down, even if someone trespasses on your property. It only gets worse if the bite causes substantial and/or permanent injury.
Sadly, there is no shortage of irresponsible dog and gun owners. It is only through education that unneeded dog shootings and all of the unintended consequences can be reduced. As an unabashed dog lover and student of the gun, I hope this post and the links provided offers some useful food for thought on the subject.