Though I served in a use of force career which was weapons systems based (thank goodness I was taught early and always remembered that a weapon was a secondary response tool and not a primary!) I tend to think that a vast majority of humans should not handle/use/own them (or other deadly machinery for that matter e.g. automobiles, trucks, lifting equipment, etc.) because of this concept in general.
Why? Most people when armed unfortunately respond incorrectly as they are wrongly empowered (bordering aggressive) and far too comfortable (blinded by a false sense of security) when they should in fact be humbled (remaining calm, cautious, and mindful) by the superior position they are in (which in fact may not be as superior as they think!).
Humans can be just plain stupid, overly emotional, too silly, and immature in the briefest moments of their lives... but that time is long enough to create great chaos, pain, and grief. I sincerely believe that any form of weapon requires a level of training, self-awareness (firm grip of reality), self-discipline (self-control), and level of maturity that most humans are simply too lazy nor patient and wise enough to ever achieve to any appreciable level to warrant having a weapon. Carry a knife or gun and you'll end up in a gun or knife fight is an old wise addage... not entirely truth but it does raise many points and questions on how escalation of force was approached and used in many deadly encounters.
I am on the fence about defensive weaponry in general... as I do believe that sound self-awareness and strong situational awareness with a calm rational mind would aid/secure most people 99% of the time.
Now there are plenty of occasions/situations that would and do require a weapon and I respect those but it is so damn hard to know where to draw the line and when to implement defensive weaponry... in fact would the individual really be trained enough and ready to respond with said weapon if they had to?
Though I may be completely off the mark as I have to admit I am quite jaded about humanity in general... I guess that's what fifteen wars, conflicts, and emergency responses in a career will do to a man.
Cheers and respects.