But does fear, in any way, protect us? The answer is, no. What protects us is our common sense. When we encounter a situation that presents a real danger to us, our common sense will alert us and we will take appropriate action to remove ourselves from the danger. Fear, on the other hand, by reducing us to a state of anxiety, actually weakens us.
Fear is an emotion. And emotion is the opposite of rationality or common sense. Fear may be based on some real event experienced years ago, but it is our emotional reaction to the event. Most likely, even at the time, the event viewed rationally would not have caused us to label it as danger and thus avoid it. But our emotions did.
That is why when we feel fear arising, we need to take the following approach. Acknowledge the fear, have compassion for it, but don’t engage it. Instead return to the present, to your breath, knowing that things are the way they are because it’s just the way it is. And knowing that if indeed there is some real danger, your common sense will let you know.
Postscript: I have now from within realized that fear and all skandhas are just a product of the mind and so their power has all but disappeared. See my post, "Proof of the Nature of Mind - Fear, Ego, and Buddha Mind,"