The Senate Intelligence Committee today is expected to receive a 900-page report from the joint congressional inquiry into the events leading up to Sept. 11, 2001, and, more relevantly, what changes in the U.S. intelligence community are required as a result of its failure to properly anticipate that heinous attack. Congress is well-known for getting exercised when bad things occur, but it often expends less energy when trying to carry out reforms. The public would do well to watch the results of the 9-11 inquiry closely.

The findings of the House and Senate intelligence committees were broadly outlined last December. Their conclusions then were damning. After scores of interviews, countless thousands of pages of documents, testimony from people, sometimes disguised to protect their identity, with first-hand information about what happened just before the attacks in New York and Washington, the inquiry found widespread failure. It concluded that the intelligence community for years had received information about the terrorists’ planned use of commercial airplanes as weapons against targets in the United States, but did little about it.

While no one had information about a specific time or target of an attack, the National Security Agency knew the men who became the 9-11 terrorists were planning attacks, likely in the United States. Famously now, an FBI agent noticed in July 2001 that Osama bin Laden was sending people in inordinate numbers to flight schools in the United States and urged the intelligence community to investigate. Between Sept. 8 and 10, 2001, the NSA intercepted but did not translate communication that indicated an attack was imminent.

These conclusions, of course, were drawn from mountains of information that pointed in many directions, and the December inquiry report properly concludes, “We will never definitively know to what extent the [intelligence] community would have been able and willing to exploit fully all the opportunities that may have emerged. The important point is that the intelligence community, for a variety of reasons, did not bring together and fully appreciate a range of information that could have greatly enhanced its chances of uncovering and preventing Osama bin Laden’s plan to attack these United States on September 11, 2001.”

Today’s report, which is to be available to the public Thursday in a redacted form, is expected to add much more depth to these observations. Among them is the proposal to add to the president’s Cabinet a director of national intelligence, who would be the White House’s primary adviser and would be charged with collecting, analyzing and disseminating information throughout the intelligence community. It would further develop with all other affected agencies a governmentwide strategy for combating terrorism. One of the key details of this is that the report recognizes that this isn’t limited to different color alerts but involves foreign policy, economic, military, intelligence and law enforcement.

The December report was toughest on the FBI and its “repeated shortcomings within its current responsibility for domestic intelligence.” It demands a major overhaul of that agency, including making counterterrorism much more of a priority. Sen. Olympia Snowe, who is on the Senate committee, has repeatedly and correctly emphasized the need to increase the number of people on the front lines of intelligence gathering and improve the communication between them and Washington. The report further urges resolution of the FBI’s “persistent and incapacitating information technology problems.”

The public will depend heavily on Congress to monitor the progress on the recommendations and ensure the nation is better prepared. Sept. 11 had the excuse that such an attack was unthinkable. No such excuse exists any longer.