I didn't get that message at all. The main character is the one who is having trouble fitting into a 'normal' life, but it seemed he was like that before he ever joined the Army. The other men on his team were not like him, and except for the younger one, didn't diss the war effort.
The men on the OED team were under pressure from being in a very dangerous job. They talked about the increased number of IEDs they were having to remove, but remember, this story takes place after the increase in al Queda operations, but before the surge in Coalition forces. I didn't come away from the movie with a negative view of the war in Iraq at all.
I agree the protagonist had problems before he joined up, but during the course of the movie those problems do become more “pronounced”, shall we say. Besides, I don’t recall that the main villain (the shadowy figure who is planting all these IED’s) ever gets caught. The implication of the movie was that the IED situation was getting worse and worse and it was, in fact, merely a matter of time before the squad got caught out by them. Lets put it this way, its not the way Al Qaida movies inc would depict their fighters.