Have you seen the video of Ethan McCord reporting his experiences on the day of the wikileaks video?
http://www.youtube.com/watch?v=kelmEZe8whIThis is just one instance, accidentally uncovered. There have been no consequences for the gunship crew. Apparently the RoE allowed them to fire on a van simply because it was picking up the wounded. The reporters and the folks who were with them were walking down the middle of the street, not firing or hiding. I'm from a military family, professional Army dating from the era when there was practically no army, and the attitude McCord reports fits in with what my great-grandfather reported from his service as a sniper in WWI, my grandfather as an infantryman in WWII and Korea, and my dad in the Dominican Republic, Vietnam (and Laos and Cambodia, but we don't talk about that, which is a related issue: if we can keep something as massive as our broader involvement in Southeast Asia secret, what chance is there for justice for an individual civilian?). Sweep everything under the rug, cover everyone's asses, if you have a problem with it there's something wrong with you, etc.
The army has a history of these things going back to the war against the Creeks. I would love to think that the US Army has its act together, and that it doesn't take outright murder for them to seriously investigate killings of civilians. But when the whole world is watching, as in the instance McCord recounts, and there are no consequences, I have little faith that it is otherwise when people are not watching.