But how does the fear of the NSA abusing my privacy compare with other random fears that I live with, like car crashes, disease, criminal conduct by a colleague, etc.
I have trouble ranking how concerned exactly I should be about the NSA
Probably should not go around being concerned to a degree that one's health declines. How upset we should be about any such abuse scales with how bad it could turn out and how long they have not improved. Stay healthy and promote endurance while working for change or fighting for a cause.