Curiouser and curiouser. I've learned to be a little suspicious when former CIA agents suddenly pop up on television describing torture sessions that have been wiped from the official record. Especially when those agents turn out not to have been actually present for the interrogation, give the opposition a morsel of truth - yep, this was torture - and yet also spin the story in ways amenable to torture advocates. You know how Fox News played the Kiriakou story.

Today, the Washington Post offers a must-read on conflicting versions of what was done to Zubaydah. The version relayed by FBI agents, and picked up by Ron Suskind, differs from the president's account. Surprise! According to retired FBI agent Daniel Coleman, who led an examination of documents after Abu Zubaida's capture in early 2002 and worked on the case, Zubaydah gave the only real information he had before he was tortured. But the CIA believed he had more info and the president authorized his extensive, months-long, Gestapo-playbook torture. This, moreover, was not some one-off 35 second waterboarding session:

Officials said, harsh tactics used on him at a secret detention facility in Thailand went on for weeks or, depending on the account, even months. The videotaping of Abu Zubaida in 2002 went on day and night throughout his interrogation, including waterboarding, and while he was sleeping in his cell, intelligence officials said. "Several hundred hours" of videotapes were destroyed in November 2005, a senior intelligence officer said. The CIA has said it ceased waterboarding in 2003.

Who should we believe? I've learned, alas, that this president is not credible in testifying to the details of his own war crimes. Recall the massive discrepancies between what the Bush administration first conceded went on at Abu Ghraib and what the photographs subsequently revealed. Now use your imagination to figure out what has really been going on under Cheney's watchful eyes. The destruction of the CIA tapes was done for one reason and one reason only: to prevent it becoming indisputable that Abu Ghraib was not just Bush policy - official Bush policy was worse.

What you see in the Zubaydah case is what always always happens when you green-light torture. You enter a world where the truth is inherently corrupt. As soon as you torture, the information is suspect. Zubaydah gave some information before torture - most crucially the identity of Khaled Sheikh Mohammed. Nothing he gave thereafter is credible.

Notice what the Zubaydah case tells us about the key argument of torture advocates like Charles Krauthammer: that torture should only be used when we already know that someone has actionable information on an imminent catastrophic threat. We're five years into the Bush torture regime and despite hundreds - and possibly thousands - of torture sessions, this was never, ever the case. Charles' abstract argument has been rendered completely moot by the evidence of the past five years. The United States made the decision to torture Zubaydah after he had already given helpful information - solely because they suspected he had more - and not in response to any knowledge of any imminent, catastrophic threat. In the beginning - not even in the end - torture became its own rationale, creating a need for torturers to justify their war crimes by finding more information through more torture, and unleashing the sadism and evil that exists in every human heart - even the most trained and professional. And then the war crimes created a need to destroy the evidence of war crimes and so the criminality of the government deepened, cloaked in the secrecy of national security. and now we are caught between an acceptance that the president is a war criminal and the need to keep fighting a vital war.

In the end, Orwell was right. The point of torture is always torture. No executive that seizes this power can be contained once it has crossed that Rubicon. And that is why - more than any other reason - this policy must be ended. Because no president can be trusted with it. This is not about Bush and Cheney as such - although they reveal what a callow president and unhinged vice-president with radical theories of executive power can accomplish. It is about the presidency and its war powers - and the need for clear limits when war knows no geographical boundaries, no expiration date and no clear distinction between citizen and non-citizen.

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