I was thinking more in terms of an actual physical encounter. As for discouraging attacks, if my size (225 lbs) and the knife visibly attached to my belt isn't enough to deter them, i don't think a wrench is gonna make them reconsider. As for LEOs, where i live most people carry a knife of some kind, and it's only got a 3" blade. If the situation is such that I'm forced to use my knife, i'm probably going to end up handing it over to the authorities anyway.
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Camping teaches us what things we can live without.
...Shopping appeals to the soul of the hunter-gatherer.