A problem with dogs is that they are one animal that will attack other animals much larger and more dangerous...as if the dog is either stupid or suicidal -- it just doesn't care and has no concern re: its own safety. That makes such an animal -- and some humans who are also suicidal -- the most dangerous assailants: They won't quit until you're dead. Or they are.
Most animals will run from another larger more dangerous animal...can't AT ALL count on dogs to do that.
So I wouldn't say a single dog is "rarely a threat" to a human. MOST times, no, but I wouldn't say "rarely." And while we have a leash-law here in Colorado, some people don't obey it and let their "friendly" dogs run loose -- I see too many dogs out there running freely, and possibly a danger to other dogs and people as well.
As for self-defense from an aggressive/attacking dog, you have two choices: Shoot it, or, when it grabs onto you, use your knife on it -- we ALL also carry fighting knives, yes? I'm talking about legal-length (as per your state law) folding knives at the very least.
A third option is calmly calling 911 (if the owner does nothing to retrieve his/her "friendly" dog)...no concern about the animal running away if you just let it keep gnawing on your leg to keep it busy, interested and entertained until police arrive. ;-)
I don't want to hurt any dogs (even with a shovel or umbrella, which I never have on me anyway), but if one DOES attack me, I'd have to kill it...any way I can. Likely, I'd use my knife (no need to wake up the neighborhood) -- and take a few good bites at the same time I'm sure. Plus, since it actually had bitten me, the dog proved its intent, whereas shooting it some distance away (if TOO distant) MAY less persuasive when one claims the dog WAS going to bite. But I'm not ruling out shooting it. And IMO, a gun would be the BEST option for sure in the event of a multiple dog (pack) attack.
In a self-defense situation, of course we do not have to sustain ANY injury FIRST before exercising self-defense, I'm just saying I'm not that worried about a single dog, even a big one (I'm big, too...sadly) so in a brief hand-to-paw encounter, a knife should be fine -- just know what specific spot on the dog (or a human) you're going to cut beforehand, don't wait to learn OJT. ;-)
The good news is that guns and knives work on both categories of animals: 2-legged or 4-legged. As for guns, its caliber hardly matters, IF you hit the target in a vital zone (or a CNS shot, which is better than torso shots).
But we're talking about DOGS...I have zero interest in fending off a Kodiak Brown Bear with my Gerber Applegate-Fairbairn Covert Double Bevel Titanium Knife, Black (Model 05786), thank you! ;-)
As for an aggressive Chihuahua (they especially don't get how small/vulnerable they are) -- I'd just squash it like a bug.
After all...a dog's got to know his limitations.
-- Harry Callahan, SFPD (ret)
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