Amb. Seyed Hossein Mousavian, a former Iranian diplomat and now a researcher at Princeton, visited the University of Maryland and tried to explain how negotiations with Iran should proceed. His presentation can be viewed in two parts:
CISSM Forum - How to Engage with Iran - Part 1 | Public Policy, University of Maryland
CISSM Forum - How to Engage with Iran - Part 2 | Public Policy, University of Maryland
Here is are Ambassador Mousavian's prepared remarks.
My own impressions were first and foremost that Amb. Mousavian is an effective advocate. He argued that the problems are purely political, not technical and that Iran is the most sanctioned nation in the world. This, he argues is hypocritical since other nuclear states such as Pakistan and Israel have established strategic relations with the US and even North Korea is subject to less sanction then Iran. The Amb. argued that US (and Western) policy is 99% sticks with no carrots and has ignored Iranian overtures. The US keeps insisting on small steps, while the Iran wants a grand bargain that would cover a range of regional issues.
Perhaps Mousavian's most compelling point was describing the legacy of mistrust between the countries. American reasons for skepticism about Iranian intentions are well-known but Iran also has its reasons for skepticism about American intentions. The 1953 coup which brought the Shah to Iran remains a critical turning point in Iranian national consciousness. American support for Saddam during the Gulf War - and particularly the blind eye the US turned to Saddam's use of chemical weapons - is a tremendous sore point to the Iranians (and understandably so.) Further, the the USS Vincennes accidentally shot down an Iranian airliner in 1988 killing 290 people. Americans may view this as a regrettable accident, but Iranians this too is an open wound. To his credit, the Ambassador did not deny that Iran two has some unfortunate incidents in its past - but merely emphasized that comparing misdeeds is unproductive in resolving the current impasse. Understanding how the Iranians see the world and view themselves as victims is important (and this goes for studying basically every country in the world.)
That being said, I was frankly disappointed that the other attendees did not press the ambassador a bit harder, but rather took him at his word. I readily admit to not being an expert on the details of the nuclear fuel cycle and IAEA protocols (read some technically informed takes here and here) - but presumably some UMD figures are and it would have been nice to get a bit more specific. The Ambassador also put some of the blame on the chaotic American political system where different interests push and pull in different ways. No disagreement here - this is what I study - but, his claims that the Iranian system does not present similar challenges was also unquestioned, although I believe that individuals who actually have been involved in reaching out to Iran tell a very different story.
Further, although the Ambassador mentioned inflammatory Iranian rhetoric, he elided a critical point: the rhetoric exists because there are important constituencies and institutions that are committed to exporting the Islamic revolution. The other players in region (Saudis, Gulf States, and Egypt) have come to a defacto peace with Israel's nuclear capability. They have a strong sense of Israel's limited ambitions and red lines. These same players are extremely nervous about Iran's potential nuclear capability.
Mousavian himself is in exile. It is unclear exactly who he represents, but he is generally believed to be aligned with the Iranian faction that very much seeks a deal with the West and would like to see the sanctions lifted. What we are probably seeing is a classic two-level game in which domestic politics and international negotiations are pulling on one another. The US side of this is well-known, but the Iranian side is less clear. However, if factions that hope to reach an accommodation with the West on the nuclear issue and lift sanctions can bring home the credible hope of an agreement, domestic politics might shift their way (sanctions are crippling Iran's economy so that relaxing them would be a huge win.)
This is an understandable ambition, but the record of the reputed Iranian moderates is not a strong one.