Preventing Friendly Fire From the Sky

Death from above.

Source: U.S. Air Force via Getty Images

As the Pentagon investigates the airstrike that killed 22 civilians at an Afghan hospital last weekend, it's crucial that authorities be as transparent as possible -- not only about what the pilots and spotters on the ground did, but also about the rules they're required to follow.

The aerial attack on the Doctors Without Borders hospital in Kunduz came from an AC-130 gunship. The AC-130, a transport plane outfitted with fearsome cannons, has traditionally not been subject to the strict "collateral damage estimation" procedure that air controllers use to determine whether fighter jets and drones get the green light to attack. The reason for the exemption, at least according to a copy of the collateral-damage guidelines obtained by the American Civil Liberties Union in 2009, is that the gunship has highly accurate "direct fire" weapons with projectiles under 105 millimeters.

With its 25- and 40-millimeter cannons and low, slow flight pattern -- and the fact that it works in conjunction with spotters on the ground -- the AC-130 is considered far less likely to cause civilian deaths than a high-speed jet dropping bombs. The fallacy of this belief is all too evident in the wreckage at Kunduz.

Were the pilots and ground troops in Kunduz operating under these looser rules of engagement? More broadly, are there good arguments for allowing the AC-130 and other direct-fire craft more freedom to engage? The answers to both of these questions will be hard to get -- because the military keeps its rules of engagement classified.

This in turn raises the question of why collateral-damage methods are classified to begin with. It would tough to make a persuasive case that releasing them would reveal vital information to the enemy. A public explanation of what happened in Kunduz will be a challenge for the Pentagon, but it's the minimum requirement after a mistake of this magnitude. Even more important, in terms of future prevention, is an assessment of the military's rules for protecting civilians. And for that debate, people outside the Pentagon need to know exactly what those rules are and how they can be improved.

(Corrects location of cannons on aircraft in second paragraph of article published Oct. 6.)

To contact the senior editor responsible for Bloomberg View’s editorials: David Shipley at davidshipley@bloomberg.net.