Vinyldetective, I think perhaps you are assuming that your righteous wrath at your dog hypothetically, having rushed at a person (which you assure us would never happen, so I don't know why you're getting so wound up about it), being booted, belted, or sprayed, would ensure you would not be similarly victimised if you went in to avenge your beloved pet.
I really wouldn't assume that. The other person would equally be hyped up on adrenalin, and anger, and ready and willing to engage - and that's assuming they're not naturally and more habitually vicious than you, or hyped up on something more. Or that they wouldn't be in a group of like minded yobs.
It's all very well, all this bluster and bravado, but as I was pointing out to my ten foot tall and bullet proof teen, sometimes discretion, and a touch of self preservation, is the better part of valour.
I think it's equally silly and really rather immature to talk about belting and kicking dogs, unless truly feeling there is no other way to seek to defend oneself or another from what you think is a real and present threat, and equally juvenile and silly to talk about getting into a brawl with someone who has been upset by having your dog (which again, you have said would never happen with your dog), engage with them against their will.