Matilda does IGP (or Schutzhund, or IPO, or Bitework, or whatever you want to call it this week). I'm not implying that she does it well, or that I fully understand all the nuance after almost two years of being involved, very peripherally with the sport.
But it does bring up the idea of Protection. After all, we do have Protection training days, and train our dogs in the skill of protection.
What is Protection? A lot of folks call me and tell me that their dog is being protective of them, and for the majority of dogs, this is untrue without equivocation. In most cases of barky, lungey, stranger-danger-y dogs, the reality is that if the person attacked, they would bolt for their lives and leave you to fend for yourself.
Matilda has been doing 'Protection' training for almost two years.
When she meets strangers on walks, she is loose and friendly, and openly affectionate. This speaks to confidence, a necessary component of protection work (and the reason my bitey, Aussie, Ruby will never do protection).
Could I 'sic' her on you? Yes - if, you had a toy, and if you made it look like fun to chase and grab, absolutely! Would you be afraid, or would there be a risk of her biting you? No, not unless your hand happened to be on the part of the toy she was targeting. In the absence of a toy, she will dismiss you as irrelevant, and she'll simply cast about looking for the promised toy.
Would most of the dogs trained in protection sports actually bite a human on command? Probably not unless that human had something about them that indicated they could be a target (Hint- don't rob a house with a PSA dog wearing a puffy jacket, or an IGP dog with a cast on your arm!)
Protection comes from confidence. Confidence is usually pretty silent. You don't see police dogs lunging and barking unless they are asked to. Most of the sport protection dogs I know are perfectly safe, social, happy dogs (some aren't, for sure, but IME, they're the exception more than the rule). The dogs that people often say are protecting them when they bark and carry on with strangers on leash or in their house, are, almost always, coming from a position of fear. They are afraid of the stranger. They are barking to build space, yelling at the person to get away, and moving towards the thing that frightens them because they are trying to frighten them into leaving. These dogs are notoriously unsocial around strangers, and can be unpredictable.
Bitesports dogs bark to demand that you play the game. They bark to close space between themselves and the target (the decoy) because they want to enjoy the game of biting stuff, and tugging. Fearful dogs bark to build space, their preference is that the target (a stranger usually) leaves. They do not enjoy the game, and they are happiest when the target leaves altogether.