This is really a discussion that should take a million scholars on a million computers to get a good answer, and what you would have would be more complicated than the sourse coude for windows.
takiing it from the beginning, I think that prepared is when a person recognizes realistic risks and takes measures to meet those risks. Is there anything realistic about expecting to see a rampaging bull elephant downtown? not really. Does one need to keep a safari grade rifle on hand in case that happens? No.That is not a realistic worry, and it's an unreasonable precaution.
Is it realistic to expect a 300 lb biker to stop your car on main street and kick your kidneys out of your ears because you accidentally cut him off? Somewhat. it is realistic and reasonable to prepare for that event, or the hundreds of thousands of other criminal actions that may happen. being prepared has no boundaries. it can happen anywhere, and it can be anyone, and carrying a 5 shot revolver is no more irrational than carrying 45 rounds. If a 5 shot revolver is what makes a person feel safe, and that person doesn't have any expectations of a massive onslaught of gangsters in his office, that's rational.
Weigh the situations you find yourself in, and prepare in accordance. In afghanistan wear armor. in the desert, carry water. In alaska, carry a .44, in your office, a .38 will almost certainly be appropriate to any event that may happen.
What does paranoid mean, psychiatrically? it means irrational. not in accordance with reality. Thinking outside of the limits of actual probability.
Carrying an AR with 3 mags to work at your job at an ice cream parlor at disney land is completely irrational. The probability against such need is absolutely astronomical, and the degree of over preparedness is irrational. Yep, that meets the clinical definition of paranoid.
Is it irrational to prepare for catastrophe?
NO. IT ISN'T.
Preparation that has no serious value is irrational and "paranoid." owning a bunker full of food is rational, as long as it isn't in new orleans under the levies. Owning a bunker full of guns and ammunition with no food is irrational anywhere. stashing a years supply of food and ammo even in your basement, and ignoring the fundamentals such as storing water and some matches is irrational.
Rational preparedness is not paranoid.
Realistically assessing your personal risks, assessing what you need to counter those threats realistically, and preparing adequately and realistically to meet those threats is not paranoid. In fact, it is the most intelligent thing that most people will ever do.
A bunker of spam and $50,000 worth of 9mm ammunition to use for trade goods is irrational and not smart.