You mean under mortar and rocket attacks or bombs going off?
From my own experience, the first time getting up close and personal with that stuff is pretty scary. But humans are adaptable beings. Now, unless it's practically on top of me (had one land about 50 feet from me this past spring. I was in a building and it shook, rattled and rolled real good), I don't even flinch. You get to where you can distinguish the sound of a mortar from a rocket from a car bomb from an IED and you also learn to gauge the approximate distance it is from you.
I still hate them, though. We've seen mostly peaceful days here since late spring and that is very easy to get used to. :)