When is an accidental civilian death not an accident?

We do know some of the details of the classified sign-off process. Many of the tough calls are made in Crowder's command center in Qatar, 700 miles south of Baghdad. It is the brain center in control of every detail of the air wars above Iraq and Afghanistan. In the air-conditioned comfort of that command hub, Crowder's team assemble explicit "air-tasking orders" for almost all of the airplanes flying over the two war zones. This includes targets that have been reviewed by commanders and vetted by attorneys.

There are two kinds of airstrikes. The first are preplanned strikes aimed at what are sometimes called "deliberate targets." An example would be a bridge, a Taliban leader, or an insurgent safe house quietly under surveillance from a circling drone. The military calls this new capability to eye a target for a long time "persistent look."

The cold, hard math of estimating collateral damage for preplanned strikes includes a calculation of the precise number of expected civilian deaths from each bomb, and it is made every day for every strike in the air wars over Iraq and Afghanistan. This grisly number is what must be weighed against the military value of the target in question. Garlasco calls that process "the macabre calculus of trying to determine how many dead civilians are worth a dead bad guy."

Planners say they go to great lengths to minimize collateral damage. The size of each bomb, ranging from 250 pounds to the extremely devastating 2,000-pound varieties, is minimized. The direction of the approach of the aircraft is altered to focus the explosive force away from civilians. And extreme prejudice is supposed to be employed when civilians are thought to be within 1,000 feet of a target, a situation referred to as "danger close." Military officials even consider what is on the ground underneath an approaching plane to minimize the damage in case a malfunction causes munitions to fall short of their targets. "We always look at our run-in heading and what is underneath the run-in heading," Crowder said. "This is a constant evolution of trying to get more and more precision."

When the assessment has been made, the planners submit the proposed airstrike to a military attorney whose job is to make sure the assessment has been done according to the law and that the anticipated casualties are within set limits.

These kinds of deliberate targets, however, represent a minority of the airstrikes in Iraq and Afghanistan. Much more common is the second category of airstrike: close air support. These are hastily arranged attacks from the air to relieve troops on the ground under enemy fire. They present a unique set of challenges with respect to protecting civilians.

Some planes are tasked to simply circle Iraq and Afghanistan, patrol air space, and wait for the troops on the ground, pinned down by enemy fire, to call for bombs. These situations are dubbed "troops in contact."

During "troops in contact" situations, the targeting for an airstrike is done by a person called a joint terminal attack controller -- the person on the ground authorized to aim the bombs. In some cases, the controller is out in the field right next to the troops in contact. And he is likely to aim those bombs using either a laser or a GPS system.

In the laser method, the controller on the ground aims the laser at the target. A pilot high above that target identifies the laser dot, and the coordinates of the dot are routed to the "smart bomb" under the nearby circling airplane. Once released, the bomb steers itself to the target.

A controller may instead rely on a GPS system and laser range finder to calculate the coordinates of the target. The controller reads the coordinates of the target to the pilot above via radio. The pilot punches in the numbers, reads the coordinates back to the controller -- and it is bombs away.

Controllers carry data on collateral damage ranges for each variety of bomb. But when troops are in a firefight and need immediate help from the air, decisions have to be made quickly, with greater emphasis on protecting U.S. forces. Steps are taken to minimize civilian deaths, but there simply is no time for a formal collateral damage assessment. Often there is only limited information on where any vulnerable civilians might be. "In those kinds of circumstances," Crowder said, "that is where you see most of the civilians being killed."

The result of improved technology and intelligence is that the military is more likely to hold its fire in 2007 than in 2003. In fact in the large majority of cases, Crowder says, commanders simply do not drop bombs at all if intelligence shows with some certainty that any innocent civilians are likely to be killed in a preplanned airstrike. "Our default is not to drop," he said in a telephone interview from Qatar. Rare situations do still arise when the excruciating decision goes the other way. "There are circumstances where we accept the fact that a target is of such value that there may be civilian casualties," Crowder said. "That is a hard calculation to make."

But all this effort to minimize civilian casualties does not stem from altruism alone. In the past two years, as American military officials have grasped the fact that they are dealing with a long-term insurgency, they've also become aware that the wars in Iraq and Afghanistan may hinge on the hearts and minds of the civilians who sometimes end up in the crosshairs. Crowder is studying "A Savage War of Peace," Alistair Horne's 1977 history of the French occupation of Algeria, illustrative of the dynamics of an insurgency. "It is an issue ultimately of growing the capacity of indigenous forces," Crowder said. "Every civilian casualty we create undermines the support for those forces and reduces the likelihood of obtaining our objective."

Other U.S. officials agree that civilian deaths from airstrikes erode support for U.S. forces and the governments they are trying to prop up. "You could win the battle and lose the war," said Air Force Maj. John Thomas, a spokesman for the International Security Assistance Force in Afghanistan, the NATO force trying to provide stability in that country and help the government led by President Hamid Karzai. "The fight is to not lose the support of the Afghan people or this fledgling Afghan government," Thomas said in an interview from Kabul.

Civilian deaths are a particularly sensitive issue for U.S. officials in Afghanistan, after being stung this summer by a string of harrowing headlines. News reports last month noted allegations of 90 civilian deaths from airstrikes over a 10-day period. Karzai held a news conference last month calling air operations over Afghanistan "careless." Then on June 19, the Agency Coordinating Body for Afghan Relief, representing nearly 100 humanitarian groups, released a statement of "strong concern" about the death toll.

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