So... what about the non-lethal options? Not as good, but hey, better than nothing. Get her some pepper spray or a tactical pen... anything that could help.
Also, without knowing any of your wives I can't really say anything, but as a woman I never gave a second thought to self-defense until I had a son. Not only was the idea of killing someone pretty horrifying, I had some interesting mental issues and deep down didn't really think I was worth defending. Now, I have a boy to get home to. Sorry BG, you're out of luck. So don't go the "you need to protect yourself" route, go with "I would be devastated if anything happened to you" instead. It'll turn it from doing something for herself to her doing it for you. That whole society conditioning thing where women are weaker and are only supposed to take care of kids or be helpful to a man is still around and can be kind of hard to get over. One of the most significant, and extremely emotional things I've ever had happen was a defensive handgun instructor looking me in the eyes and saying "I have met you, and I know you now. Your life is worth defending. You have my permission to defend yourself." I'd still never thought of it that way before, it was all about protecting my son, not myself.
Oh, and as for the "Yes Dear:"
"Yes Dear." That answer is her "tell" that she's lying. I've known it for years, and even told her I know that "Yes Dear" is just her way of getting me to stop talking about whatever I'm talking to her about.
She knows you know! She can now honestly use "Yes" to mean "No" and technically not be lying. Been there, done that... my husband knows that when I use something along those lines, it means I'm not ready to talk about it yet.
The most important thing for a guy to remember when dealing with a girl is this: It doesn't have to make any sense to be very real to her. Ask questions; if she doesn't answer she might not know herself yet. Or, she's embarrassed, or thinks you'll think it's stupid. No arguing here, just listen. Nudge later. :wink:
And start with the less-lethal options... once she's in the mindset that she can/should protect herself, she might start being more comfortable with the idea of carrying a gun.
At any rate, there's a woman's POV. Everyone is right with the "don't bug/nag her about it," but this might be why.