"We are profoundly sorry. We did all we could," J. Cofer Black, former director of the CIA's counterterrorism center, told the independent commission reviewing the 2001 hijackings.
"The shortage of money and people seriously hurt our operations and analysis," Black said at a hearing Tuesday.
In a day of finger-pointing, the panel's chairman, former New Jersey Gov. Thomas Kean, said two scathing reports compiled by the commission's investigators amounted to "an indictment of the FBI," while Attorney General John Ashcroft took a veiled swipe at the Clinton administration.
"I think there was substantial mistakes all the way back from the Clinton administration and I think the 9/11 commission is going to be able to identify those," former Sen. Bob Kerrey told the CBS News Early Show.
The officials' testimony came in a week when President Bush said it might be time to overhaul the CIA and FBI and as commissioners considered ways to fix the terror defense system.
The bipartisan panel's hearing on Wednesday was to examine ways to prevent future domestic terrorist attacks, including possibly expanding the powers of the director of central intelligence and establishing a domestic intelligence agency, such as MI5 in Britain.
Asked about such an overhaul, Mr. Bush.
"I look forward to seeing what the 9/11 commission comes up with," the president told reporters at a White House news conference. He refused to issue any apology for the attacks.
Among those scheduled to testify Wednesday were CIA Director George Tenet, FBI Director Robert Mueller and officials with the Homeland Security Department and the Terrorist Threat Integration Center.
On Tuesday, the commission said in a preliminary report that delays and missteps in linking terrorism suspect Zacarias Moussaoui to the al Qaeda terrorist group in the weeks before the attacks were emblematic of chronic problems within the FBI, including limited intelligence and analysis capabilities, outdated technology, poor information-sharing and floundering attempts at reorganization.
"Despite recognition by the FBI of the growing terrorist threat, it was still hobbled by significant deficiencies," the commission said.
Louis J. Freeh, who headed the bureau from 1993 to mid-2001, bristled at Kean's "indictment" charge.
"I would ask that you balance what you call an indictment, and which I don't agree with at all, with the two primary findings of your staff," Freeh said. "One is that there was a lack of resources. And two, there were legal impediments" that made it difficult for agents to pursue terrorism investigations.
John Lehman, a former Navy secretary and commission member, told the Early Show that the budget problems can only be blamed for part of the problem.
"Certainly the functions in retrospect were underfunded but that's not why things went wrong," Lehman said. "They went wrong because we have a totally dysfunctional organization doing our intelligence."
Former Attorney General Janet Reno also spoke of a lack of resources but said the FBI did a poor job keeping track of the information its agents gathered.
"The FBI didn't know what it had," she said. "The right hand didn't know what the left hand was doing."
Her successor, Ashcroft, defended himself against allegations that he wasn't attentive to the terrorist threat. He blamed the Clinton administration for not acting in the previous eight years.
"The simple fact of Sept. 11 is this: We did not know an attack was coming because for nearly a decade our government had blinded itself to its enemies," Ashcroft said. "Our agents were isolated by government-imposed walls, handcuffed by government-imposed restrictions and starved for basic information technology. The old national intelligence system in place on Sept. 11 was destined to fail."
But former FBI acting director Thomas Pickard told the commission that after he began briefing Ashcroft twice a week on the threats, Ashcroft told Pickard "he did not want to hear this information any more." Ashcroft denied making that statement.
A recently declassified Aug. 6, 2001, intelligence memo given to Mr. Bush summarized the al Qaeda threat and cited 70 FBI field investigations under way.
Mr. Bush said Tuesday night that the memo contained "nothing new" in terms of disclosing that Osama bin Laden and al Qaeda hoped to attack the United States.
He was heartened, he said, by the disclosure that the FBI was conducting numerous investigations.
But Pickard testified that the number 70 was "somewhat inaccurate" — he said the actual number was classified — and that the cases involved individuals linked to al Qaeda around the country. It turned out none was involved in the Sept. 11 plot.
The White House said Tuesday that the CIA analyst who wrote the memo met Monday night with members of the commission.
The commission reports noted some successes in cracking earlier terrorist cases. But the FBI was unable to stop the 19 hijackers from using commercial airliners as weapons, killing nearly 3,000 people on Sept. 11.
The inability of the FBI to link Moussaoui to al Qaeda was a prime example, the commission concluded in revealing previously unreported details about the investigation of the terrorism suspect.
Moussaoui was taken into custody Aug. 16, 2001, on immigration charges while trying to learn to fly a Boeing 747 at a flight school in Minnesota. A dispute between FBI agents in the field and supervisors meant no warrant was quickly obtained to search his computer, the commission said.
It wasn't until after the attacks that the FBI learned that an imprisoned terrorist — convicted Los Angeles airport bomb plotter Ahmed Ressam — had told agents he recognized Moussaoui from Afghan training camps run by al Qaeda.
Moussaoui now is awaiting trial on charges of conspiracy related to the Sept. 11 plot.