From reading your posts it appears you are convinced that the withholding was intended to allow the terrorist plot to go forward.
No, not at first, the withholding was done to hide the CIA culpability in the Cole bombings. The CIA had photographed everyone at the Kuala Lumpur al Qaeda planning meeting and then let them walk away to carry out the Cole bombing. The CIA was desperately trying to hide this fact. Why Tom Wilshire blocked FBI Agent Doug Miller's CIR on Mihdhar and his multi-entry visa for the US from going to the FBI on January 5, 2000 is still a mystery to me. It appears that the CIA just did not want this name to ever get to the FBI for some as of yet unknown reason. This was 10 months prior to the Cole bombing.
To hide the Kuala Lumpur meeting, the CIA along with FBI HQ units they had subjugated, in particular the Bin laden unit at FBI HQ, had criminally obstructed the FBI criminal investigation by the FBI Cole bombing investigators numerous times.
Then the CIA realized that to hide this criminal obstruction they had to continue to hide the information that Khalid al-Mihdhar and Nawaf al-Hazmi had been at the Kuala Lumpur meetings with Walid Bin Attash, the mastermind of the Cole bombing actually planning this attack.
When Mihdhar and Hazmi were found to be inside of the US on August 22, 2001, this criminal conspiracy continued, although at the time, Wilshire, the entire CIA management and many managers at the FBI HQ also knew that Mihdhar and Hazmi were inside of the US only in order to take part in a massive al Qaeda attack that would kill thousands of Americans.
When these high level CIA and FBI managers allowed Corsi and Middleton to shut down Bongardt’s investigation of Mihdhar and Hazmi they all had to know that the direct result of their actions would be to allow the al Qaeda terrorists to murder thousands of Americans in the massive al Qaeda attack they had been warned about since April 2001.
Gillespie was never part of this inner circle of this conspiracy. Wilshire had asked Alec station management when he was moved over to the FBI ITOS to spy on Bongardt and his team, to get a low level IOS agent up to speed on the Kuala Lumpur meeting, apparently so he had someone he could use as a source into the CIA and their cable data base when he needed it. The CIA assigned this to Gillespie on July 13, 2001. When she discovered the cable on August 21, 2001, that said Hazmi had entered the US on January 2000, she immediately took this to the INS who said that both Mihdhar and Hazmi were inside of the US. She had already discovered a cable on July 24, 2001 that was FBI Agent Doug Miller's CIR to be sent to the FBI on Mihdhar’s passport and multi-entry visa for the US, that had written on the bottom, "Please hold off for now", Deputy Chief of the Bin laden unit, Tom Wilshire, and then found the cable by “Michelle” Wilshire’s CIA desk officer, that said that this information had been sent to the FBI when it had not.
Since Corsi and Wilshire immediately realized that Gillespie, who apparently had never been warned to keep any information on Mihdhar and Hazmi secret from anyone outside of the CIA, had for the very first time allowed this information to go outside of the CIA and Alec station, they also realized that they were now forced to start an investigation for Mihdhar and Hazmi. But they also realized that if Bongardt ever started this investigation for Mihdhar and Hazmi and then found the photo of Walid Bin Attash at Kuala Lumpur he would have immediately known that the CIA and FBI HQ had criminally withheld this information from him and his team numerous times, and many people at both the COIA and FBI HQ would have gone to prison for years.
To prevent this they decided to start an intelligence investigation for Midhar and Hazmi knowing that the OIPR would never allow a parallel criminal investigation for these terrorists at the same time. On August 22, 2001, Corsi called Craig Donnache and said it was urgent that he immediately start an intelligence investigation for Mihdhar and Hazmi, which he did on August 28, 2001. When Donnachie told Corsi he was going to start an intelligence investigation for Mihdhar and Hazmi Corsi emailed Wilshire immediately and said, “Craig will open an intelligence investigation for Mihdhar”.
When Bongardt accidentally got Corsi’s EC to start this investigation for Mihdhar and Hazmi on August 28, 2001, he called Corsi who said that it was illegal for him and his team to even look at her EC since it had information from a NSA cable, the December 1999 cable that said Khalid, and Nawaf were traveling to an important al Qaeda planning meeting in Kuala Lumpur. What she did not tell Bongardt was that she had already gotten the NSA release in writing to give this exact information to Bongardt just the day before. She also never told Bongardt that she already knew the CIA had a photograph of Bin Attash at the Kuala Lumpur meeting, knew that this directly connected both Mihdhar and Hazmi to the planning of the Cole bombing, and even knew that the CIA had been keeping this hidden for Bongardt and his team so Bongardt would never have enough information to start any investigation for Mihdhar and Hazmi.
When this investigation was given to Robert Fuller an intelligence agent at the New York office, he as so inexperienced that he could not find any information in the FBI data base, “Choicepoint” on Mihdhar or Hazmi when it was actually there. When he called Corsi on September 5, 2001 to get her permission to get Mihdhar’s credit card number from Saudi Arabian Airlines so he could continue with his search for any information on Mihdhar and Hazmi in the FBI data base, she refused to give him permission to call Saudi Arabian Airlines, clearly aware that this would make his investigation for Mihdhar fail, which it did.
Almost 3000 people paid with their lives for this monumental treachery by these very high level managers at both the CIA and FBI HQ.