WASHINGTON — The CIA’s top leaders failed to use their available powers, never developed a comprehensive plan to stop Al Qaeda, and missed crucial opportunities to thwart two hijackers in the run-up to September 11, 2001, the agency’s own watchdog concluded in a bruising report released yesterday.

Completed in June 2005 and kept classified until now, the 19-page executive summary finds extensive fault with the actions of senior CIA leaders and others beneath them. “The agency and its officers did not discharge their responsibilities in a satisfactory manner,” the CIA inspector general found.

“They did not always work effectively and cooperatively,” the report stated.

Yet the review team led by Inspector General John Helgerson found neither a “single point of failure nor a silver bullet” that would have stopped the attacks that killed nearly 3,000 people.

In a statement, CIA Director Michael Hayden said the decision to release the report was not his choice or preference, but that he was making the report available as required by Congress in a law President Bush signed earlier this month.

“I thought the release of this report would distract officers serving their country on the front lines of a global conflict,” Mr. Hayden said. “It will, at a minimum, consume time and attention revisiting ground that is already well plowed.”

The report does cover terrain heavily examined by a congressional inquiry and the September 11 Commission. However, the CIA watchdog’s report goes further than previous reviews to examine the personal failings of individuals within the agency who led the pre-September 11 efforts against Al Qaeda.

Mr. Helgerson’s team found that no CIA employees violated the law or were part of any misconduct. But it still called on then-CIA Director Porter Goss to form accountability boards to look at the performance of specific individuals to determine whether reprimands were called for.

The inquiry boards were recommended for officials including: a former CIA director, George Tenet; his deputy director for operations, Jim Pavitt; the counterterrorism center chief, Cofer Black, and the agency’s executive director, A.B. “Buzzy” Krongard.

In October 2005, Mr. Goss rejected the recommendation. He said he had spoken personally with the current employees named in the report, and he trusted their abilities and dedication. “The report unveiled no mysteries,” Mr. Goss said.

Mr. Hayden stuck by Mr. Goss’s decision.

Providing a glimpse of a series of shortfalls laid out in the longer, still-classified report, the executive summary says:

• American spy agencies, which were overseen by Mr. Tenet, lacked a comprehensive strategic plan to counter Osama bin Laden prior to September 11. The inspector general concluded that Mr. Tenet “by virtue of his position, bears ultimate responsibility for the fact that no such strategic plan was ever created.”

•The CIA’s analysis of Al Qaeda before September 2001 was lacking. No comprehensive report focusing on Mr. bin Laden was written after 1993, and no comprehensive report laying out the threats of 2001 was assembled. “A number of important issues were covered insufficiently or not at all,” the report found.

•The CIA and the National Security Agency tussled over their responsibilities in dealing with Al Qaeda well into 2001. Only Mr. Tenet’s personal involvement could have led to a timely resolution, the report concluded.

•The CIA station charged with monitoring Mr. bin Laden—code-named Alec Station—was overworked, lacked operational experience, expertise, and training. The report recommended forming accountability boards for the CIA Counterterror Center chiefs between 1998 and 2001, including Mr. Black.

•Although 50 to 60 people read at least one CIA cable about two of the hijackers, the information wasn’t shared with the proper offices and agencies. “That so many individuals failed to act in this case reflects a systemic breakdown. … Basically, there was no coherent, functioning watch-listing program,” the report said. The report again called for further review of Mr. Black and his predecessor.
While blame is heaped on Mr. Tenet and his deputies, the report also says that Mr. Tenet was forcefully engaged in counterterrorism efforts and personally sounded the alarm before Congress, the military and policymakers. In a now well-known 1998 memo, he declared, “We are at war.”

The trouble, the report said, was follow-up.

In a statement, Mr. Tenet said the inspector general is “flat wrong” about the lack of plan.

“There was in fact a robust plan, marked by extraordinary effort and dedication to fighting terrorism, dating back to long before 9/11,” he said. “Without such an effort, we would not have been able to give the president a plan on September 15, 2001, that led to the routing of the Taliban, chasing Al Qaeda from its Afghan sanctuary and combating terrorists across 92 countries.”

The inspector general did take exception to findings of Congress’s joint inquiry into September 11. For instance, the congressional inquiry found that the CIA was reluctant to seek authority to assassinate Mr. bin Laden. Instead, the inspector general believed the problem was the agency’s limited covert-action capabilities.