Why isn't our army allowed to do certain things over in Iraq and Afghanistan, they make rules for war?

They are called rules of engagement. There are certain acts that we can not partake in and that other countires should not either. I believe they are regulated by NATO (I could be wrong on that) and breaking these rules come with huge consequence. It is war, you're right, but there must still be some organization and method to it all... as odd as that may sound