Tomorrow, in its print edition, The New York Times starts to answer the question, with reporter Douglas Jehl disclosing the contents of a newly declassified memo apparently passed to him by Sen. Carl Levin of Michigan, the top Democrat on the Senate Armed Services Committee.

It shows that an al-Qaeda official held by the Americans was identified as a likely fabricator months before the Bush administration began to use his statements as the basis for its claims that Iraq trained al-Qaeda members to use biological and chemical weapons, according to this Defense Intelligence Agency document from February 2002.

It declared that it was probable that the prisoner, Ibn al-Shaykh al-Libi, "was intentionally misleading the debriefers" in making claims about Iraqi support for al-Qaeda's work with illicit weapons, Jehl reports.

“The document provides the earliest and strongest indication of doubts voiced by American intelligence agencies about Mr. Libi's credibility,’ Jehl writes. “Without mentioning him by name, President Bush, Vice President Dick Cheney, Colin L. Powell, then secretary of state, and other administration officials repeatedly cited Mr. Libi's information as ‘credible´ evidence that Iraq was training Al Qaeda members in the use of explosives and illicit weapons.

“Among the first and most prominent assertions was one by Mr. Bush, who said in a major speech in Cincinnati in October 2002 that ‘we've learned that Iraq has trained Al Qaeda members in bomb making and poisons and gases.´’

A White House spokeswoman said she had no immediate comment on the D.I.A. report, according to the Times.

“Mr. Libi was not alone among intelligence sources later determined to have been fabricating accounts,’ Jehl continues. “Among others, an Iraqi exile whose code name was Curveball was the primary source for what proved to be false information about Iraq and mobile biological weapons labs. And American military officials cultivated ties with Ahmad Chalabi, the head of the Iraqi National Congress, an exile group, who has been accused of feeding the Pentagon misleading information in urging war.’

Libi is in custody, apparently at Guantánamo Bay, Cuba, where he was sent in 2003.

According to Jehl, Secretary of State Colin Powell relied heavily on Libi for his speech to the United Nations on Feb. 5, 2003, saying that he was tracing "the story of a senior terrorist operative telling how Iraq provided training in these weapons to Al Qaeda."

Also at E&P....Editor Greg Mitchell's column on war hero/reporter Joe Galloway's lunch this week with Donald Rumsfeld:

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