The final report of the commission investigating the Sept. 11, 2001, attacks recommends a major restructuring of the nation's intelligence community and includes broad criticism of the White House, Congress and other parts of the U.S. government for failing to detect, thwart and better respond to the deadly hijackings, according to panel members and other officials.

The book-length report -- being readied for public release on Thursday -- has been endorsed by all 10 of the bipartisan panel's members. It features many of the findings that emerged from public hearings and staff investigations, including the conclusion that al Qaeda and Iraq did not form a close working relationship, commission officials said.

But the final report goes beyond the detailed findings of the commission's staff, scolding Congress for poor oversight of the nation's counterterrorism efforts and urging specific and dramatic reforms that include creation of a powerful national counterterrorism center, according to administration officials and those involved in drafting the document. The new center would have far greater authority than the Terrorist Threat Integration Center opened by the CIA last year, officials said.

The report also recommends a Cabinet-level office and director to oversee the CIA, the FBI and other intelligence agencies, as the New York Times reported yesterday, but one official familiar with the report said that was only part of a broader reorganization aimed at shaking up the intelligence community. The five Republicans and five Democrats on the commission say they have jointly agreed not to discuss details of their recommendations before the report is released.

The proposals follow two reports by the House and Senate intelligence committees that faulted the government's intelligence gathering, particularly at the CIA, and come amid a flurry of legislative proposals to remake the intelligence community.

The report caps a remarkable 20-month investigation in which the independent commission -- created amid acrimony by Congress and initially opposed by President Bush -- gained unprecedented access to closely held presidential briefings, transcripts of interrogations of high-level al Qaeda leaders and tens of thousands of pages of other classified material. The panel also privately interviewed Bush, Vice President Cheney and their predecessors, Bill Clinton and Al Gore.

Deadline to Publish

Through 17 detailed statements assembled by its staff and released this year, the commission has already dramatically altered the public understanding of how 19 al Qaeda hijackers were able to carry off the deadliest terrorist attack in U.S. history. The commission revealed, for example, previously unknown conflicts among al Qaeda's leaders and the hijackers, and told of a plot originally intended to involve 10 aircraft in an assault on the East and West coasts.

The panel has been racing over the past three weeks to finalize the report so that it could be released before a July 26 statutory deadline, the same day the Democratic Party's national convention opens. Commission officials feared that issuing the report that day could have opened the panel to political attacks. Nearly 600 pages long, the findings will be available through bookstores, the Internet and the Government Printing Office.

Commissioners interviewed last week said the entire panel was involved in drafting and editing the findings, and reached agreement on how to address some of the most politically sensitive topics. As late as yesterday, officials said, the report was still being edited and the panel continued wrestling with White House lawyers over classification issues.

"The staff statements were genuinely the work of the staff," said Vice Chairman Lee H. Hamilton (D), a former congressman from Indiana. "The report that we will issue next week is a commission product and has been very carefully examined by the commissioners, line by line. . . . There are certainly topics in the report that were not touched on in the staff statements."

Several commissioners said the resulting report was not compromised by the desire of Hamilton, Chairman Thomas H. Kean (R) and others on the panel to reach unanimity.

"We have not pulled any punches," said commissioner Timothy J. Roemer (D), a former Indiana congressman. "We will have dynamic structural changes and a dramatic moving of the boxes to better reflect moving from a Cold War to a hot jihadist threat, but it's also important to keep your eye on tradecraft and nuts and bolts."

Led by co-chairmen who have attempted to steer the panel away from partisan debate, and relying on a staff assembled without direct involvement by the two major political parties, the commission's published statements so far have struck a centrist, judicious tone. In many respects, the panel's work has been closer to the fact-finding, conspiracy-debunking Warren Commission of the mid-1960s, which investigated the assassination of President John F. Kennedy, than to the reform-oriented Church Commission, which exposed assassination plots and CIA abuses during the mid-1970s.

The commission staff has already absolved Saudi Arabia's government of direct support for al Qaeda and debunked widespread reports that Osama bin Laden inherited $300 million. (He received a $1 million annual allowance for about two decades, the commission found.) Panel members also have knocked down questions raised by last year's congressional investigation into Sept. 11 intelligence failures involving possible help for the hijackers by the Saudi Embassy in Washington.

On the politically charged election-year argument over whether the Clinton or Bush administration had the more aggressive approach to battling al Qaeda, the commission has produced evidence on both sides. Scores of previously classified documents and e-mails the commission has already disclosed show, for example, that national security adviser Condoleezza Rice was correct when she argued in public hearings this spring that unlike Clinton, Bush adopted a policy early in 2001 that explicitly sought to eliminate al Qaeda.

Yet the commission has released documents showing that the practical steps Bush planned to take during the early years of his presidency imitated much of Clinton's unsuccessful strategy of negotiating with the Taliban, even though the threat of a massive al Qaeda terrorist attack seemed to be rising.

Drawing Connections

Some of the commission's most politically sensitive judgments this week will address conspiracy-tinted questions echoing in the current presidential campaign, such as whether al Qaeda and Saddam Hussein's Iraq had a significant relationship, and whether the White House made special arrangements to fly bin Laden relatives out of the United States in September 2001, as alleged in Michael Moore's new documentary film, "Fahrenheit 9/11."

The commission made headlines on June 16 by reporting that its investigators had found "no credible evidence that Iraq and al Qaeda cooperated on attacks against the United States," and that although there were meetings between Iraqi officials and bin Laden's group during the 1990s, the contacts "do not appear to have resulted in a collaborative relationship." Bush and Cheney cited evidence of contacts between Iraq and al Qaeda as a justification for the U.S.-led invasion of Iraq in March 2003.

The final report will not alter the staff's general conclusion, commissioners said. But it is likely to lay out again specific evidence of the past contacts, allowing partisans to reargue their positions.

In June, commission investigators detailed new evidence about bin Laden's past relationship with Hussein. The staff cited statements by two senior bin Laden associates apparently in U.S. custody who "adamantly denied" that there were "any ties" between al Qaeda and Iraq. The panel also reported that bin Laden at one point "sponsored" Islamic radical guerrillas in Iraq who were fighting to overthrow Hussein and replace his secular government with a religious one.

At the same time, investigators reported that when bin Laden lived in exile in Sudan between 1991 and 1996, the Sudanese government -- seeking to preserve its relationship with Hussein -- successfully pushed bin Laden to end aid to the anti-Hussein guerrillas and later arranged meetings between Iraqi and al Qaeda officials. Some of the commission staff's language about these contacts in the June statement was more tentative than the political argument that followed their disclosure. The investigators reported that, on three occasions, a senior Iraqi intelligence officer "reportedly" visited Sudan and eventually met with bin Laden in 1994. But after bin Laden asked for help with weapons and military training, Iraq's government "apparently" did not respond.

Commissioner John F. Lehman (R), a former Navy secretary who has cited possible evidence of Iraq-al Qaeda ties, said the report would include "more information" on Iraq. He also said the report overall will include "less editorializing and more fact" than the staff statements.

"Some people might have stated things more starkly or attempted to draw more editorial judgments," Lehman said, referring to the report in general. "What did not happen is that the conclusions got watered down or we tried to fudge the evidence. This is not a watered-down report. . . . Everybody endorses it, and it wasn't because it was turned into homogenous fudge."

Commission investigators have looked in depth at what they earlier labeled the bin Laden flight, a charter plane on which relatives of the al Qaeda leader departed the United States after the attacks, apparently because they feared for their security. As of two months ago, the commission staff had found "no evidence" to contradict the FBI's conclusion that none of the Saudis on the flight had involvement in the attacks or with bin Laden's other terrorist ambitions.

In their initial inquiry, commission staffers were unable to learn who at the White House helped to arrange the bin Laden flight. Eventually, however, the request was passed to counterterrorism coordinator Richard A. Clarke. "Each of the flights we have studied was investigated by the FBI and dealt with in a professional manner" before it was allowed to fly, and none of the planes was permitted to take off before U.S. airspace was reopened to commercial aviation, the commission staff concluded.

The flight with bin Laden relatives departed on Sept. 20 with 26 passengers, including three private security guards. The FBI interviewed 22 of the people on board, asking many of them detailed questions, commission investigators said. FBI agents checked "a variety of databases" for watch lists and other information, found no matches and ultimately concluded that the passengers were of no interest to investigators.

Warnings Missed

Such politically charged mysteries have heightened the commission's profile, but they lie on the periphery of its mandate, which was to investigate why the Sept. 11 attacks occurred, whether they could have been prevented and what reforms would best strengthen the country against similar strikes in the future.

Both Kean and Hamilton have said the evidence suggests the plot could conceivably have been thwarted, but the commission has not cast judgment on whether stopping the hijackers was truly probable or merely theoretical. Regardless, commission investigators have already laid out a mass of detailed evidence suggesting that there were many more specific opportunities to break up the hijacker cell than previously understood.

These included at least two, and possibly as many as eight, instances in which hijackers presented passports that had been manipulated fraudulently; several statements on hijackers' visa applications that could have been proved false; and poor communication among U.S. computers preventing plotters from being tagged as suspicious when they crossed borders. The panel also identified by name as many as 10 hijacker candidates who were dropped from the plot, including accused Sept. 11 conspirator Zacarias Moussaoui. Commission investigators have disclosed new facts, details and documents about the United States' often-secret struggles with al Qaeda dating back more than a decade. But the greatest amount of new detail disclosed by the commission -- consistent with its mandate -- involves the run-up to the attacks during 2001, the way the strikes unfolded on Sept. 11 and the shortcomings in the response of emergency personnel and U.S. air defenses.

Among other things, the final report will revisit the controversy ignited by Clarke, who charged in a best-selling book and at intensely watched commission hearings that Bush and his national security team had been slow, distracted and cautious about the bin Laden threat during the first months of 2001. Without adopting Clarke's argument, the commission staff has documented previously unknown meetings, memos, chronologies and messages from this period, many of which support Clarke's position or quote from classified warnings he issued inside the Bush White House.

Clarke's e-mails and memos culminated in a dramatic note to Rice in early September, in which Clarke poured out his frustrations and, in eerily prescient language that forecast the commission's work, urged Bush's policymakers to "imagine a day after a terrorist attack, with hundreds of Americans dead at home and abroad, and ask themselves what they could have done earlier."

The report will expand on the commission's earlier findings that al Qaeda's contacts with Iran were far more advanced than previously believed, and that the two may have developed a relationship of convenience that included cooperation in attacks such as the Khobar Towers bombing in Saudi Arabia. Time magazine reported that the commission has found that eight to 10 of the Sept. 11 hijackers may have passed through Iran before joining the hijacking plot.

Staff writer Mike Allen contributed to this report.

Former counterterrorism chief Richard A. Clarke testified this spring that the Bush administration was slow to react to the bin Laden threat in early 2001.Sept. 11 commission Vice Chairman Lee H. Hamilton, left, and Chairman Thomas H. Kean have worked to keep the panel from partisan debate. Commissioner Timothy J. Roemer, right, said, "We have not pulled any punches."