reporter: sergeant heeter s job is to protect his boss. the lieutenant colonel, war squadron commander who ironically is trying to build spreading pockets of peace in this violent, mountainous slice of eastern afghanistan. heeter, take it easy, all right? this deployment so far, had two rockets land within 25 meters. i got hit with a suicide bomber from about seven feet away in the beginning of the deployment. i was the only one to walk out without a scratch. had a 600-pounder hit me. reporter: the 600-pounder was a very bad day. the suicide bomber pulled up, stopped right here, and detonated. reporter: no soldiers were killed or wounded. only afghan children. those little kids playing out in front of their house. 600 pounds of explosives in the back of a truck goes off. totally innocent. they have no idea.