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Did We Know About Mohamed Atta?

9/11: Why would the Pentagon buy and destroy copies of a book by a former Army intelligence officer? Could it be perhaps because it contained information on how the 9/11 attacks might have been prevented?

The impulse to dismiss this as just another conspiracy theory is overwhelming. Yet the fact is that the Pentagon bought and destroyed 10,000 copies of a book, "Operation Dark Heart," written by Lt. Col. Tony Shaffer, a Bronze Star recipient and career Army intelligence officer, that contained a chapter on a pre-9/11 intelligence operation, Able Danger.

In a statement, the Pentagon said it "decided to purchase copies of the first printing because they contained information which could cause damage to national security." The books were destroyed on Sept. 20.

The book, critical of operations in Afghanistan, had been cleared by Shaffer's superiors at U.S. Army Reserve Command, but was seized after objections by Pentagon intelligence officials. It also comments on the departure of Gen. Stanley McChrystal, whose resignation was prompted by statements he made in a Rolling Stone interview.

Granted, Pentagon and administration sensitivity to criticism is high after that episode and after publication of Bob Woodward's latest book, "Obama's Wars."

But book burning? Lt. Col. Shaffer has since agreed to a redacted version of the book, but where are the champions of the public's right to know?

Shaffer went public in August 2005 with details about a secret military intelligence unit called Able Danger in which he was involved. The unit, using a technique known as data mining, determined a year before 9/11 that four of the future hijackers were al-Qaida operatives, including 9/11 ringleader Mohamed Atta.

After his revelation, Shaffer was stripped of his security clearance and cast into military limbo. In October 2006, Rep. Christopher Shays, who was chairman of the Subcommittee on National Security, Emergency Threats and International Relations, wrote to Shaffer's superior, Maj. Gen. Elbert Perkins, about the reasons for the clearance revocation and whether it was a retaliatory move.

Shays wrote that an "investigation of security clearance retaliation" showed that "the Defense Intelligence Agency (DIA) used the security clearance system in an improper manner against LTC Shaffer" and that Shaffer's alleged misuse of a government cell phone and travel voucher was a matter of administrative, not punitive, action under the uniformed code of military justice.

Was this an attempt to silence Shaffer and discredit and bury information about Able Danger?

A 2006 Defense Department inspector general's report on the whole matter was kept under wraps until an unredacted copy was recently obtained by Fox News.

Curiously, it omits any reference to possible identification of Atta and his cohorts before 9/11.

According to Fox News, which talked to five witnesses named in the report, all five said their statements to investigators were distorted or key information was left out backing up assertions that lead hijacker Atta had been identified as an al-Qaida operative before 9/11.

One of the redactions DIA sought in "Operation Dark Heart" was the removal of references to a meeting between Shaffer and the executive director of the 9/11 Commission, Philip Zelikow.

Shaffer alleges that in that meeting, which took place in Afghanistan, Zelikow was informed about the existence of Able Danger and its identification of Atta before 9/11. The reaction, Shaffer said, was "stunned silence."

Shaffer says that Zelikow told him to get in touch when he returned from Afghanistan. When Shaffer tried to contact the 9/11 Commission upon his return, he was told it was no longer interested.

No mention of this meeting was made in the 9/11 Commission report.

If Shaffer's story is bogus, it should be publicly debated and exposed. It certainly isn't a danger to national security in that case. If it is true, it is unclear if the information could have prevented 9/11, but it might have.

All we know for sure is that sunlight is the best disinfectant and part of the answer may be in the pages of a book the Pentagon felt it was necessary to burn.