The CIA's top leaders failed to use their available powers, never developed a comprehensive plan to stop al-Qaida and missed crucial opportunities to thwart two hijackers in the run-up to September 11, the agency's own watchdog concluded in a bruising report released Tuesday. 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.