You work security? Perfect. Get a large Mag-light and don't worry about the knife. Seriously. I have seen what a motivated individual swinging a big metal flashlight can do to another human being. If I had a choice between being armed with a small knife or a 3 D-cell metal flashlight, I'd reach for the flashlight, every time. Plus, it is perfectly useful in other ways, and is as close to innocuous as you can get, in a hoplophobe-rich environment.
You hold it in the interview stance in your strong hand (since you have no gun), fingers wrapped around the body just behind the bell for the lens. the body of the flashlight extends back over your shoulder. This is the perfect position to blind someone with the light, and you can bring it down overhead in a nasty chop, or you can swing it sideways (twist your hips) in a slice parallel to the ground.
It makes a very eerie hollow *CONK* when it connects solidly with someone's head. That someone usually stops whatever it was they were doing, pretty quickly.
Mike
PS Of course, you weren't trying to hit them in the head. You were just caught off guard when they rushed you, and their head got in the way of your flashlight. It happens.
PPS Seriously, the suprascapular strike point is a place for which cops aim when they do strikes, and twisting/turning/fighting suspects sometimes get bonked on the melon unintentionally. I saw that happen just last week, actually.
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