Rifle ready, Cpl. Joe Johnson nimbly stepped around mounds of trash and pools of raw sewage, handing out strawberry Twizzlers to scabby, barefoot children. Cpl. Joseph Johnson on patrol near Husseiniya, Iraq.photo by Louie Favorite/AJCIt saddens Johnson to think this desperate poverty and filth were the last things his son saw before he was killed last year. For more than a year, Johnson fought to follow in his son’s footsteps to Iraq. There was a sense of soldierly duty, but what most drew him here was his desire for vengeance. “I can shoot an insurgent and not lose a bit...