A CIA medical officer who was assigned to monitor the interrogation of an Al-Qaeda operative named Abu Zubaida sent a message to his superiors on Aug. 4, 2002, the day the CIA first used the technique known as “waterboarding.” He hauntingly titled his cable: “So it begins.”

“Longest time with the cloth over his face so far has been 17 seconds. This is sure to increase shortly. NO useful information so far … I’m head[ing] back for another water board session.”

And so dawned a nightmare era in which a CIA with little expertise in interrogation worked desperately to gather information that might protect a nation severely traumatized by the events of Sept. 11, 2001.

Zubaida “cried,” “begged,” “pleaded” and “whimpered,” but the waterboarding continued and the interrogation progressed. An Aug. 8, 2002, cable noted: “Several on the team profoundly affected … some to the point of tears and choking up.”

What started that day at a secret prison in Asia came full circle Tuesday with a public accounting by the Senate Intelligence Committee. Reading the report, you feel a measure of the remorse experienced by those onlookers 12 years ago. While the report’s tone struck me as overly prosecutorial, I have no question that the committee was right to disclose it.

This is a political document, not a dispassionate history, but that’s part of its value: There simply is no way for a democracy to get past a trauma like the interrogation issue without an honest public accounting. It’s a strange healing process, ripping off the scab, exposing our wounds; perhaps it’s like the self-flagellation of the early saints.

The best illustration that confronting past evil leads to a kind of national redemption is Germany. Don’t misunderstand: The CIA’s interrogation practices aren’t remotely comparable to the crimes of Nazi Germany. But the Germans insisted on facing their unconscionable history, admitting their guilt over and over, preserving the humiliation of their defeat in 1945 even on the walls of their parliament.

Writing recently in The New Yorker, George Packer likened the healing process to psychoanalysis: “Germany has brought its past to the surface, endlessly discussed it, and accepted it, and this work of many years has freed the patient to lead a successful new life.”

The Senate report describes a CIA that rushed recklessly into the interrogation abuses. But what struck me was how unprepared the agency was for handling captured Al-Qaeda suspects.

Most CIA officers were gentleman spies who would echo the demurrals of John Limond Hart when asked in 1978 about the harsh interrogation of KGB defector Yuri Nosenko: “It has never fallen to my lot to be involved with any experience as unpleasant … To me it is an abomination.”

The agency, fearing a “second wave” of Al-Qaeda attacks, turned in 2002 to two psychologists who claimed to be experts in interrogation. Based on their experience training American pilots to resist harsh interrogation, these consultants devised a list of 12 techniques to break the will of Al-Qaeda detainees. In addition to waterboarding, they suggested “use of insects” and “mock burial,” which apparently were rejected. Their company was paid a grotesque $80 million for its services.

The Senate report overreaches in its claim that torture was “not an effective means of acquiring intelligence.” Would that we could be so sure. It’s wiser to be agnostic about effectiveness, but clear about ethics. We can’t know whether information gained from harsh interrogation helped provide essential leads that allowed the targeting of Osama bin Laden. That’s why banning torture is a moral choice: Because in doing so, we may indeed lose useful information. That’s the risk we take in doing the right thing.

What’s least convincing about the report is its picture of an agency that maliciously deceived the rest of the government. This revives the notion of the CIA as a “rogue elephant” that was propounded by the Frank Church Committee in the 1970s but has been rebutted by many historians. The real story of intelligence abuses in the 1950s and 1960s is that they were ordered by presidents or their henchmen, who didn’t want to know the dirty details.

This ambiguity comes through in an Aug. 2, 2002, memo after Condoleezza Rice, then national security adviser, was told the Justice Department had approved waterboarding and the other techniques we now describe as torture: “‘Dr. Rice had been informed that there would be no briefing of the president on this matter,’ but that the [CIA director] had policy approval to employ the CIA’s enhanced interrogation techniques.”

And so it began.