“Know they enemy and know yourself, never in one hundred battles will you be in peril.” –Sun Tzu
Part of negotiating is understanding your opponent’s aims. In doing so, we are able to adapt our style and demands to address their issues in order to further our own aims. One of the problems with recent American nuclear negotiations with Iran is that we have not really attempted to understand Iran’s position or why it conducts itself in the way it does. This lack of understanding hinders our negotiations, and hopefully in the forthcoming negotiations the US will keep in mind the point of view of Iran, and use that to further our aims. Hopefully using this knowledge we will be able to bridge the trust gap.
This is not to excuse their past behavior. We cannot simply explain away their IAEA violations (mostly in the occultation of nuclear enrichment) by attempting to understand them. Much like a regular criminal, understanding the Circumstances does not excuse the crime, but it is more helpful to attack the root of these problems rather than punitive action after punitive action.
So why would Iran want nuclear weapons, even in the face of such international condemnation?
Defense: this is the big one. Iran saw how the US behaved with regards to Iraq declaring their lack of nuclear ambitions and opening up their sites. Even when DG Blix noted that the IAEA inspectors did not find any evidence of nuclear skullduggery, the US effected regime change at the end of a rope. Not to mention we have been enemies of Iran longer than we were enemies of Saddam. The lesson from North Korea is that once you have obtained the Bomb, the kid gloves come on, because heaven forefend that we would give a reason to use it. Local defense is not as much of a concern, now that the aforementioned Hashemite Kingdom of Iraq is no longer in any position to threaten the Islamic Republic.
Regional Hegemony: Ah, here we go. Much to the chagrin of broad-brush painters, Iran is not an Arabic country. Being full of Persians, but also a part of the Middle East gives them a standoffish relationship with the Kingdom of Saud and points eastward. Were they to obtain a bomb, Iran would suddenly rocket to the top of influential and powerful countries in the region. The return to the glory days of empire would be a powerful incentive for wistful power brokers in Teheran. Nuclear weapons would also help balance out the multinuclear region of Israel, Russia, China, Pakistan, and India.
Religious Hegemony: In addition to being an ethnic minority compared to its westward neighbors, Iran is also one of only three Sh’ia-majority countries (Azerbaijan and Bahrain join it). While A.Q. Khan and Pakistan gave the world “The Muslim Bomb,” Iran could be the country to give the world “The Sh’ia Bomb.” While this would further set them apart from most of the Muslim world (and as Ayatollah Khomeini has declared nuclear weapons “un-Islamic”), it would also grant them a measure of respect from its coreligionists. This might be more of the respect one must give a loaded gun, but respect nonetheless.
Bonus answer: It’s not: Surprise! It is also possible that Iran is not seeking nuclear weapons (Leon Panetta seems to think they aren’t), but merely keeping their cards close to the vest. Repeatedly, the IAEA technocrats (Blix, ElBaradei, Amano, et al.) have found that Iran had been keeping within the Non Proliferation Treaty (NPT) guidelines, while the bureaucrats (The IAEA Board of Governors who have frequently brought Iran before the UNSC). Were we to take the past feelings that might be clouding our (American) judgment from the equation, enrichment is allowed under the NPT and peaceful nuclear energy is allowed under the NPT. However, the previous reasons for why they might seek a weapon also work as answers as to why they want to remain ambiguous about their nuclear program.
So in negotiating with Iran about the future of their nuclear program, we need to keep the Iranian point-of-view in mind in order to talk them down off the ledge, or at least have them show us that they were never going to jump in the first place.