Is Fear Always a Negative?

Kat asked, in a comment, “Is fear always a negative thing?” I briefly reflected, and here’s where I am now:
I think of fear as a continuum between “an alert edge” and “paralyzed with fear.” What we generalize as “fear” starts at alertness, because at that point you can no longer be fully “open”—you are looking for something, even if you don’t know what. By the time you increase your fear to paralyzation, you’re toast. In the middle range are an infinite number of emotional and psyiological states which have a fearful component. A less fearful, more fear-less life would seem to have a number of important benefits. It might be worth reflecting on those in depth.