I've been reading about various US wars recently, and there is a ton of evidence that the US military command has never cared about killing civilians, and in fact has purposefully killed civilians. I've been reading about wars from World War II on.
Robert McNamara has talked recently about not only dropping the atomic bomb on Nagasaki and Hiroshima, but the massive firebombing of Tokyo and most major Japanese cities which is less known in the US. And of course, Dresden and other cities were firebombed as well. McNamara said LeMay said if the US lost, they'd have been tried as war criminals.
As the No Gun Ri massacre investigation uncovered, officers weren't afraid to put in written documents orders to shoot at civilians during the Korea war. The only fear was releasing them in FOIA's - even all these years later, the government kept blocking out the sections were orders to shoot civilians. Then of course there was the bombing of dikes and dams which killed untold many civilians. Here's a memo regarding the orders to shoot civilians:
What happened in Vietnam is more well known. More tons of bombs were dropped on North Vietnam than were dropped in World War II. Then there were massive operations such as Wheeler/Wallowa, of which the My Lai massacre was a small part of.
Seeing the Abu Ghraib pictures and knowing torture is still happening in Iraq and Cuba, while the administration is more concerned with covering it up than stopping it, I wonder what is being kept from me by the embedded reporters and corporate media. The complete destruction of the city of Fallujah seems to be a good indicator.
Of course, the commands to disregard civilian life, or to actually actively kill civilians usually comes from officers, and usually from on high down. What stops things from becoming even worse is enlisted men often refuse to shoot at civilians. This is something that has happened throughout history. It depends on the person. Looking back at a well known incident, My Lai, when Lt. Calley (who himself had been ordered into a situation that led to this) ordered his men to fire at civilians, some did, some didn't, and some enlisted men from other units saved civilians. Enlisted soldiers sometimes care about preserving civilians lives, but when one looks over the history, orders coming down from the chain of command rarely do.