We all make mistakes. We know we make mistakes. I don't know any military commander, who is honest, who would say he has not made a mistake. There's a wonderful phrase: "the fog of war." What "the fog of war" means is: war is so complex it's beyond the ability of the human mind to comprehend all the variables. Our judgment, our understanding, are not adequate. And we kill people unnecessarily.
Comment in The Fog of War (2003), documentary film by Errol Morris