"Iran is in the eye of the storm," he says, noting that regional neighbor Pakistan and arch-foe Israel both have nuclear weapons, though neither are signatories like Iran of the nuclear Non-Proliferation Treaty. "It is the duty of every government to equip itself to defend itself. Any state in Iran's position should go after the latest military technology."

Since the NIE report, US officials have raised the bar for Iran's compliance, insisting that Tehran acknowledge that it once had a nuclear weapons program. The new US intelligence described in the IAEA report includes designs for a 400-meter shaft for remotely testing explosives from six miles away, which "would be relevant" to weapons research."   excert from article by Scott Peterson

These are the very same tactics used by the US and Britian to eventually invade Iraq.  They constantly demanded more.  When orginal requests were satisfied, they implied, lied and demanded more compliance.  Basically, there wasn't a way for Iraq to comply since at each juncture the US and Britian would "raise the bar".