Wow...now we are all inventing crimes...lol.
No, I see it as stooping to the same level. You can't control what others do...you CAN control what you do. If you want to shoot and maybe kill someone over, whatever, are you really any better? And is it really defensive...or revenge? And is it really making the situation better and safer? What consequences are you willing to live with if things go horribly wrong? I think it's very complicated. I don't think it is a matter of "own gun=be safe", but too often the argument is boiled down to that.
Besides...what about preventative measures? Security alarms, having one of those "help I have fallen and can't get up" devices, knowing emergency escape routes, building one of them cool panic rooms...whatever...

Or, what about dealing with the issues in society or with individuals who are involved in these crimes to do everything that can be done to stop these crimes from even happening in the first place so it doesn't get to the point where anyone has to pick up a gun.