Was supposedly an 'insider' in Iraq who knew about WMDs. Talked to the German BND prewar, who talked to CIA. 
Wikipedia has an article on him: wikipedia:Curveball
In April 2005, Tenet said that somebody shoulda told him Curveball was nutso before now.
Tenet had made a speech in 2004, in which he talked about trailers that might have been used for WMD production. In the statement above from April 2005, he says that when he made that 2004 speech, and was talking about anonymous 'sources' for his information on trailers, one of the sources was Curveball. 
Bob Drogin Edit
wrote a book about him...
Norbert Juretzko Edit
"the case officers didn't notice inconsistencies in his story." 
Writes a lot about Curveball, in his book Shadow Warriors.
"One of Drumheller's superiors, who asked not to be quoted by name, said he was struck when he watched the 60 minutes piece because he knew that Drumehller's claims were just flat-out wrong. "Drumheller never told -me- that CURVEBALL was a fabricator. Didn't happen" pg 287
"the CURVEBALL fiasco is yet another intelligence failure that falls squarely on the shoulders of the CIA's inpet - some say, disloyal - European Division chief, Tyler Drumheller."
Question: err.. who says 'disloyal'?
Pete Hoekstra Edit
Talks about how the German BND, that was talking with Curveball, didn't want to let the CIA talk directly to Curveball.. claims the reason was because of too many Leaks within the CIA.... so they gave info to the CIA, which was wrong...
"The Commission on Weapons of Mass Destruction reports the Intelligence Community seriously misjudged the status of Iraq's biological weapons program in the 2002 National Intelligence Estimate and other pre-war intelligence products. The primary reason for this misjudgment was the Intelligence Community's heavy reliance on a source—codenamed “Curveball”—whose information later proved to be unreliable.
This misjudgment could have been avoided if we were able to receive key information from our allies. The decision by a foreign intelligence service not to share a critical source seriously undermined our ability to assess his credibility. Despite numerous requests by the CIA, the foreign government refused to provide us direct access to Curveball because of past leaks from within our government."
Q:OK. we have basically, some diametrically opposed statements of fact here. One says that Drumheller never said Curveball was a wackjob, the other side says Drumheller did warn them and his warnings were 'unheeded'.
Q: One says the German BDP wouldn't let direct access to Curveball, because the US leaks too much info. What?
only source on WMDs? Edit
On The Daily Show, Aug 11, 2008, Jon Stewart iterviewed ron suskind, and said that there seemed to be only one souce, Curveball, that colin powell and others were using, while ignoring Habbush. This would seem to contradict testimony by Tenet and others that there were many sources for information before the war.
Probably lots of people from the INC and Chalabi, the INA and Allawi, and Naji Sabri, Habbush, Curveball, and who knows how many others? The CIA had contacts all through the Iraqi government and military going back to the 90s, and maybe before back to the 80s.... hell, there might be a few left over from the CIA's involvement in the 50s and 60s in Iraq. . . .
which ones said what about wmds?
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