What is paranoia? It's generally believed to be a state of suspicion about your fellow human beings that is out of proportion to the actual threat they represent.
Is being prepared for an emergency even though that emergency is relatively unlikely a question of paranoia?
I have an article in the current issue of KnifeForums Magazine called Safer in Suburbia. It's all about the types of survival gear you can carry on you, in a briefcase, in your car, and stored at your home in case of natural emergency, civil unrest, crime, and so forth. There is every chance that most of this gear, which I haul around personally, will never see use.
But I'd rather be prepared than unprepared.
Self-defense -- and, more broadly, preparations for unnamed and unspecified emergencies -- is all a question of hedging your bets, gambling against chance. You can't win every bet, but you can cheat as much as possible.