A new book reveals that the CIA made a deal with Pakistan that allowed the United States to begin its drone assassination program in exchange for the murder of an enemy of Pakistan. In an excerpt in tomorrow's New York Times, journalist Mark Mazzetti outlines how Pakistan, which was resistant to allowing the CIA to begin killing targets within its borders, asked the CIA in 2004 to kill Taliban-ally Nek Muhammad, in exchange for allowing the CIA to begin its drone strike assassination program in the country. Pakistan would take responsibility for the death of Muhammad, and the CIA would never be mentioned in official accounts of his death.

Mazzetti writes,

Mr. Muhammad and his followers had been killed by the C.I.A., the first time it had deployed a Predator drone in Pakistan to carry out a "targeted killing." The target was not a top operative of Al Qaeda, but a Pakistani ally of the Taliban who led a tribal rebellion and was marked by Pakistan as an enemy of the state. In a secret deal, the C.I.A. had agreed to kill him in exchange for access to airspace it had long sought so it could use drones to hunt down its own enemies.

The article goes on to detail how the CIA was looking to end its network of secret prisons, which had recently been the subject of a blistering internal report. Worried that high-ranking members of the CIA might one day be tried for war crimes, the agency settled on the tactic of simply killing its enemies, and not capturing them, transforming "an agency that began as a cold war espionage service into a paramilitary organization." Mazzetti's book, The Way of the Knife: The C.I.A., a Secret Army, and a War at the Ends of the Earth, which details the transformation of the CIA, comes out on Tuesday.

The secret deal with Pakistan set off a chain of events which has led to thousands of killings of people and the wholesale transformation of the CIA from "the long-term jailer of America's enemies to a military organization that erased them." Spurred by a new generation of officers who were not yet working during President Gerald Ford's 1975 ban on assassinations (after the CIA had killed foreign leaders for several years after World War II), the CIA has now undergone a drastic shift from a spy organization to a military force that lacks oversight and kills with relative impunity.

"You can't underestimate the cultural change that comes with gaining lethal authority," John E. McLaughlin, then the C.I.A.'s deputy director, told Mazzetti.

Pakistan still denies that the CIA had any involvement in the death of Mr. Muhammad, and of course, the CIA has never confirmed the existence of a drone assassination program.