2003
I think it's important to put the revelations that Iran halted its nuclear "program in 2003 primarily in response to international pressure" in the context of the broader trends in US-Iranian relations that Gareth Porter (among others) have reported on. Specifically, in 2003 we know that the Iranians attempted a diplomatic opening to the United States. Porter reported that in exchange for actually getting something, Iran was prepared to abandon its nuclear program in a hard-to-reverse way:
To meet the U.S. concern about an Iranian nuclear weapons program, the document offered to accept much tighter controls by the International Atomic Energy Agency (IAEA) in exchange for "full access to peaceful nuclear technology." It proposed "full transparency for security [assurance] that there are no Iranian endeavors to develop or possess WMD" and "full cooperation with IAEA based on Iranian adoption of all relevant instruments (93+2 and all further IAEA protocols)."
There have been some efforts to discredit what Porter, Flynt Leverret, and others have said about this attempted opening, but the NIE's conclusions about Iran's nuclear program seem to strongly support it. With their secret enrichment activities exposed, the Iranian regime was reconsidering the utility of continuing such efforts in the face of international awareness and disapproval of them. The Bush administration then decided to squander this opportunity and focus on saber-rattling and dreams of regime change. But the thing about pressure is that you've got to be willing to take yes for an answer instead of just blundering around.
Meanwhile, how outrageous is it that the best twelve months of alarmism from Bush & Cheney have come in the context of an environment where they've long had access to the intelligence community's assessment? Answer: Very outrageous.