Rumsfeld is completely responsible for Abu Ghraib

Or, in plainer English, Sy Hersh has a new book! That link gives you a long excerpt from the text, and I wish I could say that Rumsfeld's responsibility was the only bad news.

There was, we now know, a fantastical quality to the earnest discussions inside the White House in 2002 about the good and bad of the interrogation process at Guantánamo. Rice and Rumsfeld knew what many others involved in the prisoner discussions did not - that sometime in late 2001 or early 2002, the president had signed a top-secret finding, as required by law, authorising the defence department to set up a specially recruited clandestine team of special forces operatives and others who would defy diplomatic niceties and international law and snatch - or assassinate, if necessary - identified "high-value" al-Qaida operatives anywhere in the world.

Equally secret interrogation centres would be set up in allied countries where harsh treatments were meted out, unconstrained by legal limits or public disclosure. The programme was hidden inside the defence department as an "unacknowledged" special-access programme (SAP), whose operational details were known only to a few in the Pentagon, the CIA and the White House.

The SAP owed its existence to Rumsfeld's desire to get the US special forces community into the business of what he called, in public and internal communications, "manhunts", and to his disdain for the Pentagon's senior generals. In the privacy of his office, Rumsfeld chafed over what he saw as the reluctance of the generals and admirals to act aggressively. Soon after September 11, he repeatedly made public his disdain for the Geneva convention. Complaints about the United States' treatment of prisoners, Rumsfeld said, in early 2002, amounted to "isolated pockets of international hyperventilation".