Wow:

A new assessment by American intelligence agencies concludes that Iran halted its nuclear weapons program in 2003 and that the program remains on hold, contradicting an assessment two years ago that Tehran was working inexorably toward building a bomb.

The conclusions of the new assessment are likely to be major factor in the tense international negotiations aimed at getting Iran to halt its nuclear energy program, and they come in the middle of a presidential campaign during which a possible military strike against Iran’s nuclear program has been discussed.

The assessment, a National Intelligence Estimate that represents the consensus view of all 16 American spy agencies, states that Tehran’s ultimate intentions about gaining a nuclear weapon remain unclear, but that Iran’s "decisions are guided by a cost-benefit approach rather than a rush to a weapon irrespective of the political, economic and military costs."

The declassified NIE findings can be found here, caveats and all. Gareth Porter passed along a secondhand report last month that Dick Cheney's office had held up the estimate for nearly a year "in an effort to force the intelligence community to remove dissenting judgments on the Iranian nuclear program, and thus make the document more supportive of [Cheney's] militarily aggressive policy toward Iran." 

P.S. Only a month ago, McConnell was telling reporters that this NIE would never be made public. What changed? Kevin Drum hazards a few guesses.

P.P.S. Joe Klein passes along this, from a "senior U.S. intelligence official":

1. the NIE was made with a "high" degree of certainty, which means there was more than one information stream confirming it.

2. our "collection" capability within Iran has improved considerably over the past few years.

3. that Iran once did actually have a nuclear weapons program but...

4. It was international attention and disapproval that caused the Iranians to quit the program, which means that diplomacy, the UN sanctions regime--all the things the Bush administration has disdained--actually matter. They certainly worked in this case, which is just wonderful news.

--Bradford Plumer