There is no way for anyone to know for sure where they would be or who they would be facing in the future....where these guys are going that they’re going to need that much firepower?
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I don't assume every opponent I might face is an "average" mugger who would get scared and run at the sight of me pulling a pistol.
Whether if 5 shot in a gun or 10 magazine load of ammo is insufficient or "that much fire power" totally depends on what you are faced with.
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Am I just naïve feeling safe with my "baby Glock" or should I start arming up?
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You don't have to carry a back-up
You don't have to carry a spare magazine
As a matter of fact, you don't have to carry anything at all.
It depends on how much you want to put up with and what you want to be prepared for.
Only carrying a "baby Glock" does not make you naive. If you don't have a realistic idea about its limitations, that would make you naive.