A congressional report blames U.S. intelligence agencies for overstating the threat of Iraq's weapons in the months leading up to the war in that country last year.
The report prepared by the Senate Intelligence Committee harshly criticizes intelligence agencies for their assessments of the Iraqi threat in the months before the U.S.-led invasion.
Committee Chairman Pat Roberts, a Kansas Republican, released a public version of the classified report prepared by his panel.
"Most of the key judgments in the October 2002 National Intelligence Estimate on Iraq's WMD programs were either overstated or were not supported by the raw intelligence reporting," he said.
"There is simply no question that mistakes leading up to the war in Iraq rank among the most devastating losses and intelligence failures in the history of the nation," said Senator Jay Rockefeller, a West Virginia Democrat and Vice Chairman of the committee.
The report criticizes agencies for focusing on intelligence that supported the idea that Iraq had WMD and ignoring information that contradicted it.
It says U.S. agencies relied too much on defectors and foreign intelligence services for information but were not able to check the reliability of such reports. The exiled Iraqi National Congress, which advocated U.S. military action in Iraq, has been accused of giving the United States misleading intelligence.
The report blames many of the intelligence failures on what it calls "a broken corporate culture and poor management", problems which it says cannot be solved by simply adding funding and more personnel. It holds outgoing CIA Director George Tenet ultimately responsible.
Mr. Tenet, who announced his resignation last month, leaves the agency Saturday. His deputy, John McLaughlin, is to take over as acting director until the president nominates and the Senate confirms a successor.
Iraq's weapons of mass destruction were cited as a key reason the United States went to war in Iraq. No such weapons have been found.
But the committee said it found no evidence that the intelligence community's mischaracterization or exaggeration of the intelligence on Iraq's weapons capabilities was the result of political pressure from the Bush administration.
Still, Senator Rockefeller says that point is still open to debate.
"That is not to say there are areas of disagreement,." he said. "There are, especially on the question of whether the administration pressured the intelligence community to reach a predetermined, in my judgment, conclusions."
Many Democrats believe the administration manipulated intelligence to make its case for war.
The Intelligence Committee does plan to consider how the administration used the intelligence in making policy decisions as the second part of its inquiry.
The panel is also considering ways to reform the intelligence community in the wake of its report.