This week at a nuclear conference in Tehran, Iran's new chief nuclear negotiator Sayeed Jalili said, "Nuclear weapons are inhuman and unacceptable. We are opposed to them on principle."
"We only want a nuclear program," the official line goes, "to fuel nuclear reactors for making electricity."
The rest of the world doesn't believe it.
France and Germany are now lockstep with the U.S. in an effort to introduce new sanctions against Iran, backed by the U.N. Security Council. China and Russia are hedging on sanctions, but they too are unsettled by Iran's nuclear program, which is already enriching uranium.
The International Atomic Energy Agency has assumed a difficult dual role: global nuclear policeman -- and honest broker. In his latest report to the IAEA Board of Governors this week, the Nobel Prize-winning Head of the Agency Mohammed el Baradei, gave Iran mixed grades for its nuclear transparency.
A "B plus" for coming clean on how and when its nuclear program secretly began, 20 years ago, when Iran was scavenging for restricted knowledge and equipment in, among other places, Pakistan.
But "C" and "D" marks for not allowing IAEA inspectors to investigate the program thoroughly, especially the parts of it that are under military control.
El Baradei does not speculate on what Iran's true intentions are. However, his diplomatically worded reports reveal skepticism.
"Iran has provided sufficient access to individuals and has responded in a timely manner to questions and provided clarifications. …However its cooperation has been reactive rather than proactive," he writes in his report to the Board of Governors.
The IAEA cannot verify that Iran has not got a secret military nuclear program somewhere hidden from its view.
In February of 2006, as a tactical move in this international diplomatic fight, Iran actually reduced the IAEA inspectors' access to its nuclear facilities.
Now, a year and half later, el Baradei writes, "As result, the Agency's knowledge about Iran's current nuclear programme is diminishing."
The Iranians deeply resent the rest of the world scrutinizing a nuclear program they, as signatories to the Nuclear Non Proliferation Treaty, have a legal right to pursue.
Iran's leaders want the world to respect their country as a sophisticated, businesslike and oil-rich state that will work to make -- and keep -- peace with its neighbors.
"The Islamic Republic of Iran is a lynchpin in the region," Jalili told delegates to the conference. "We are prepared to maintain security in our country, and the whole region."
The U.S. and its allies, on the other hand, see a paranoid, unstable theocracy with an exploding population and Arab enemies on all sides; a country that might decide it needs nuclear weapons precisely in order to "maintain security in the region," and will not hesitate to make them if it can -- in spite of Jalili's professed disdain for them.
The bell has rung for a new round in this fight -- and the gloves are about to come off.