use or form tools to their greatest effect
 These are technological solutions to improve your chances of survival in a motor car accident.
That's exactly what we want.  Anything you can form from on-site materials limits you to muscle power & a 5'-6' range.  As long as I'm not in the first room attacked, I would have a much better chance of survival with a concealed carry weapon than something I can put together on the spot.
Most of us aren't talking about everyone being armed but those who have gone the extra step to get a CCW permit.  I wouldn't have a problem with a two tier system.  Getting the second tier would give the right to carry anywhere except a court room.  Maybe two or three day class and actually score the range results.