For the past eight months, there has been a furious battle raging behind closed doors at the White House, the C.I.A., and in Congress. The question has been whether the Senate Select Committee on Intelligence would be allowed to use pseudonyms as a means of identifying characters in the devastating report it released last week on the C.I.A.’s abusive interrogation and detention program. Ultimately, the committee was not allowed to, and now we know one reason why.

The NBC News investigative reporter Matthew Cole has pieced together a remarkable story revealing that a single senior officer, who is still in a position of high authority over counterterrorism at the C.I.A.—a woman whom he does not name—appears to have been a source of years’ worth of terrible judgment, with tragic consequences for the United States. Her story runs through the entire report. She dropped the ball when the C.I.A. was given information that might very well have prevented the 9/11 attacks; she gleefully participated in torture sessions afterward; she misinterpreted intelligence in such a way that it sent the C.I.A. on an absurd chase for Al Qaeda sleeper cells in Montana. And then she falsely told congressional overseers that the torture worked.

Had the Senate Intelligence Committee been permitted to use pseudonyms for the central characters in its report, as all previous congressional studies of intelligence failures, including the widely heralded Church Committee report in 1975, have done, it might not have taken a painstaking, and still somewhat cryptic, investigation after the fact in order for the American public to hold this senior official accountable. Many people who have worked with her over the years expressed shock to NBC that she has been entrusted with so much power. A former intelligence officer who worked directly with her is quoted by NBC, on background, as saying that she bears so much responsibility for so many intelligence failures that “she should be put on trial and put in jail for what she has done.”

Instead, however, she has been promoted to the rank of a general in the military, most recently working as the head of the C.I.A.’s global-jihad unit. In that perch, she oversees the targeting of terror suspects around the world. (She was also, in part, the model for the lead character in “Zero Dark Thirty.”)

According to sources in the law-enforcement community whom I have interviewed over the years, and whom I spoke to again this week, this woman—whose name the C.I.A. has asked the news media to withhold—had supervision over an underling at the agency who failed to share with the F.B.I. the news that two of the future 9/11 hijackers had entered the United States prior to the terrorist attacks. As I recount in my book “The Dark Side,” the C.I.A. got wind that one of these Al Qaeda operatives, Khalid al-Mihdhar, had obtained a multiple-entry visa into the United States eighteen months before 9/11. The agency also learned, months before the attacks, that another Al Qaeda operative, Nawaf al-Hazmi, had flown into Los Angeles. Yet the C.I.A. appears to have done nothing. It never alerted the F.B.I., which had the principal domestic authority for protecting the U.S. from terror attacks. Its agents had, in fact, been on the trail of at least one of the hijackers previously, but had no way of knowing that he had entered the United States. Nor did the C.I.A. alert the State Department, which kept a “TIPOFF” watch list for terror suspects.

Amazingly, perhaps, more than thirteen years after the 9/11 attacks, no one at the C.I.A. has ever been publicly held responsible for this failure. Evidently, the C.I.A. was adamant in its negotiations with the White House and the Senate Intelligence Committee that the American public never learn the names of anyone directly involved in this failure.

As NBC recounts, this egregious chapter was apparently only the first in a long tale, in which the same C.I.A. official became a driving force in the use of waterboarding and other sadistic interrogation techniques that were later described by President Obama as “torture.” She personally partook in the waterboarding of Khalid Sheikh Mohammed, the architect of the 9/11 attacks, at a black site in Poland. According to the Senate report, she sent a bubbly cable back to C.I.A. headquarters in 2003, anticipating the pain they planned to inflict on K.S.M. in an attempt to get him to confirm a report from another detainee, about a plot to use African-American Muslims training in Afghanistan for future terrorist attacks. “i love the Black American Muslim at AQ camps in Afghanuistan (sic). … Mukie (K.S.M.) is going to be hatin’ life on this one,” she wrote, according to the report. But, as NBC notes, she misconstrued the intelligence gathered from the other detainee. Somehow, the C.I.A. mistakenly believed that African-American Muslim terrorists were already in the United States. The intelligence officials evidently pressed K.S.M. so hard to confirm this, under such physical duress, that he eventually did, even though it was false—leading U.S. officials on a wild-goose chase for black Muslim Al Qaeda operatives in Montana. According to the report, the same woman oversaw the extraction of this false lead, as well as the months-long rendition and gruesome interrogation of another detainee whose detention was a case of mistaken identity. Later, in 2007, she accompanied then C.I.A. director Michael Hayden to brief Congress, where she insisted forcefully that the torture program had been a tremendous and indispensable success.

Readers can speculate on how the pieces fit together, and who the personalities behind this program are. But without even pseudonyms, it is exceedingly hard to connect the dots. It seems entirely possible—though, again, one can only speculate—that the C.I.A. overcompensated for its pre-9/11 intelligence failures by employing overly harsh measures later. Once they’d made a choice that America had never officially made before—of sanctioning torture—it seems possible that they felt they had to defend its efficacy, despite mounting evidence to the contrary. If so, this would be worth learning. But without names, or even pseudonyms, it is almost impossible to piece together the puzzle, or hold anyone in the American government accountable. Evidently, that is exactly what the C.I.A. was fighting for during its eight-month-long redaction process, behind all those closed doors.