What would be traumatizing is blowing out a six year old's brains in your first firefight, which the article mentions was the case for Sam Siatta's squadron. I hardly think going to a poor country in itself is the main source of trauma for veterans. It's the violence that happens there and the later realization of the utter futility of the whole thing, the realization that you were used as a pawn for the benefit of weapons manufacturers and imperialistic geopolitical maneuvering.