Hey Prizewriter, great self-defense site and general advice. However, maybe YOU don't have to worry about getting attacked (you live in a gated community, maybe? Never go out? Weigh 300 pounds and everyone crosses the street when they see you?) But not everyone is in this situation. I live in a "safe" city but have had to defend myself more than once (one time defending another person). It's one reason why I train. Hopefully it won't happen again, but my theory is I'll be able to startle someone enough to give me time to get lost. Paranoia isn't necessary but preparation is. And no, I don't go around looking for fights, I'm not a police officer or prison guard, and I don't wander around alone in the middle of the night.
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God grant me a good sword and no use for it. -- Polish proverb