A book excerpt that appears on the front page of Sunday's New York Times reveals that the United States' drone program in Pakistan was allowed to begin because the CIA agreed to take out a man the Pakistani government considered an enemy of the state. In The Way of the Knife: The C.I.A., a Secret Army, and a War at the Ends of the Earth (out on Tuesday), journalist Mark Mazzetti describes the details of the deal: In 2004, Pakistani officials were growing increasingly frustrated by Nek Muhammad, a Taliban-affiliated militant who led a string of successful attacks against Pakistan's military in the country's tribal areas over the years. Their attempts to kill Muhammad on their own had failed, as had a brief truce with him.

"Pakistani officials had, for several years, balked at the idea of allowing armed C.I.A. Predators to roam their skies. They considered drone flights a violation of sovereignty, and worried that they would invite further criticism of [then President Pervez Musharraf] as being Washington’s lackey," writes Mazzetti. However, the military's intelligence officials finally agreed to allow the American drones into their airspace after then CIA director George Tenet offered to murder Muhammad in exchange. When a missile blew up Muhammad's South Waziristan compound — killing him and several others — the Pakistani military took credit for the deaths. The CIA was never mentioned in any official accounts of the incident, which was targeted killing conducted by an American drone in Pakistan. As we now know, the attack preceded hundreds of similar strikes, though the targets are at least supposed to be people who pose a direct threat to American interests.

Mazzetti goes on to note that CIA's shift toward the drone program was prompted by a desire to get rid of its network of secret prisons, which, as an internal report had recently revealed, were rife with prisoner abuse, leaving the agency vulnerable to charges of war crimes, among other things. "[The Muhammad] deal paved the way for the C.I.A. to change its focus from capturing terrorists to killing them, and helped transform an agency that began as a cold war espionage service into a paramilitary organization." While increased public awareness of drone killings has put some pressure on President Obama and current CIA head John Brennan to be more transparent about the program, scaling it back will be even more difficult than a 13-hour filibuster. As Mazzetti writes, "With a generation of C.I.A. officers now fully engaged in a new mission, it is an effort that could take years."

Originally published in New York Magazine.