...When was the last time a kid got a hold of a spare tire and killed himself or one of his friends with it?...When was the last time somebody accidentally killed his roomate with a fire extuinger because he thought his roomate was an intruder?...
Or a kid accidentally gotten a hold of household chemicals, power tools or matches...
At this point the thread could easily get into the "Guns don't kill people, people kill people" thing. And, I wholeheartedly agree with that.
If it comes to a life-threatening situation, I would use anything at my disposal to defend my family and myself. In that case, a fire extinguisher, spare tire, or anything else would suit me just fine. Heck, I would command my chihuahua to go for the jugular if I thought it would help.
I shoot multiple times a week but have yet to shoot at anyone. But, I will if I have to. I never had to use a fire extinguisher but would if I had to, even if it required using it across someone's face.
Unlike a household item, though, a firearm gives you at least three things:
knock down power when all else fails, distance (and therefore, time to react) and perhaps to make a strong case to the attacker that you mean business. Not always, but there is a good chance that an attacker will see me holding my 45 cal Glock and choose to leave. Again, not always, but you never know. Yes, I know, someone who enters your place and knows you're inside probably already wants to deal with you, but that only goes to show you do need to be prepared.
Training goes a looong way. If you feel comfortable using a gun, then mistakes are kept to a minimum.
As for carrying on a bike, think about a subcompact 9 mm of some kind. Don't underestimate a 9 mm as a defensive weapon (especially with hollow points), since the lower recoil s easier to control. Resist the temptation to use way too much power. I've never done it, but I assume that a holster that fits around the back of the waist, around the beltline would be the most comfortable while riding. Or, one on the anke, since a subcompact is relatively easy to store there. Just trying to keep the thread motorcycle related

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