It's a freaking Agatha Christie mystery trying to figure out what was in those redacted *bleeps* by the CIA on the NYT article this past week. The censure was unwarranted, the authors say, because all the redacted items had already been presented in previous articles.
The authors insist that the U.S. missed an opportunity for a general rapprochement with Iran, especially when Iran assisted the U.S. against the Taliban in Afghanistan following 9/11. But the episodes to support this thesis are missing because of the redactions. However, one guess at one critical redacted paragraph goes like this:
"When Tehran sought a quid-pro-quo to strengthen its own security and offered to exchange captured Al-Qaeda leaders for a small group of senior commanders among the Mojahedin-e Khalq (MEK) cadres in Iraq, the administration refused to consider any such exchange, even though the MEK has been designated a foreign terrorist organization by the U.S. Department of State. The United States backtracked on a promise to disarm MEK troops, and canceled scheduled meetings with Iran, accusing it of harboring al-Qaeda leaders implicated in suicide bombings in Saudi Arabia. "
MEK tries desperately to be seen as a legitimate organization, and it gives out sandwiches to poor assistants in the European Parliament in pursuit of this goal, but it continues to sit on "terrorist organization" lists in both Europe and the United States. However, their efforts may have had some influence here (?).. but the U.S. indecisiveness as noted in the previous paragraph was probably more influenced by the following realization, from a WaPo article in 2003, a fact which has been long forgotten and therefore probably redacted:
"Some Pentagon officials, impressed by the military discipline and equipment of the thousands of MEK troops, began to envision them as a potential military force for use against Tehran, much like the Northern Alliance in Afghanistan. But the MEK is also listed as a terrorist organization by the State Department."
The other major item redacted from the article is mention of meetings between the U.S. and Iran in Geneva in 2003 discussing rapprochement between the two countries, which eventually broke down because both sides accused the other of harboring/failing to disarm terrorists (Al Qaeda for Iran, and MEK for the U.S.). There are other citations relating to the redactions at Raw Story.