There are two scenarios for Iran to reach its foreign policy goal of hegemony in the Middle East and international respect. One involves deciding that a nuclear weapon will not get it what it wants and the other involves deciding it will but not telling us about it. It may be a long time before Iran decides and before we know what the decision is, or even if there has been a decision. And no decision is final.
Since the Revolution in 1978, the twin drivers of Iranian foreign policy have been the desire for international respect and hegemony over the Middle East. The debate now ongoing in Iran is whether or not those two goals can be achieved fastest, cheapest and most reliably with or without nuclear weapons. The fact that the Ayatolla and his court hs allowed these negotiations to go on indicates that at the highest level of the what Iran calls a government (which which is a geographically overlapping set of often warring facation) indicates that the non-nuclear side of the argument has a strong chance of being ascendent. The economic sanctions have seriously reduced Iran's ability to project both soft and hard power and have reduced its economy to a shadow of what it would need to even think about being the ME's leading power.
It remains to be seen if the non-nuclear faction, which is essentially the negotiating team, can close the deal and keep it closed for 15 years. Supreme Leader Ali Khamenei sent the following tweet on March 21: "We reject US fraudulent offer of reaching a deal w #Iran first then lifting sanctions. Lifting sanctions is a part of deal not its outcome." This means that Foreign Minister Javad Zarif and his team of many American-trained negotiators will have to be very convincing that they got what Iran needs to build up its role in the ME without giving up forever any chance of becoming a nuclear power.
So we are facing two scenarios:
#1. Zarif wins the argument and it stays won for 15 years. Iran follows the treaty, allows the inspections , grows its economy and uses the money and the new freedom to strenghten its role int eh ME, often in way the US and Israel oppose.
#2. Zarif does not win the argument, but the Supreme Leader pretends he did and signs the agreement, only to start cheating at the margins. The cheating will be strategic, with the intent of forcing the US and the 5 powers into the position of having to decide when cheating is serious enough to cancel the treaty and reimpose sanctions. In this scenario,Iran bets that the US and its allies will get into a long debate about when to pull the plug on marginal cheating, and over what exactly constitutes cheating and what is really just reaching a common definition.
We won't know for some time which scenario Iran follows, and it can follow both simultaneously either because of warring faction or to create strategic confusion. One signal will be whether or not Kerry and Zarif publicly disagree on the major outlines - of the framework. Some disagreement will be necessary for them to sell the agreements at home, and the wording was carefully constructed to enable each to interpret sections favorably. However, outright contradiction on what is in the framework will signal scenario 2.
The second signal will come during the technical discussion, especially over inspections; if these break down or result in language too fuzzy to satisfy either side, we will know that Iran has opted for scenario 2 and is not willing or able to pretend it is following #1.
If the technical negotiations are completed to everyone's satisfaction and signed b y Obama and the Supreme Leader, the third signal will come into play, the response of the Revolutionary Guards. The RG is the popular and military guardian of Iranian sovereignty, as well as a major exporter of assistance to Iran's vassal military allies like Hezbollah. If the guards defy the agreement and block or hinder inspections, we will know that the Supreme Leader has opted for scenario 3. it is possible that RG responses are timed to fortify a Scenario 2 strategy to buy time while not giving much up.
My betting is that the Supreme Leader has not opted for either scenario, but wants an agreement to go forward to give himself a second option in his quest for hegemony and respect. He will continue to listen to the arguments of the pro-nuclear factions and, if the lifting of sanction does not provide the economic resources to project both soft and hard power and force the US and EU and China to deal with Iran on a more equal basis, he will begun marginal cheating and cause inspection problems, trying to keep it below a sanction threshold as long as possible while he builds cash reserves and military and resource stockpiles.
Which means that, if this agreement is signed, the US and Europe will not only have to calibrate sanctions reductions, but also support a robust Iranian economy, lest the Supreme Leader decides that the nuclear option is better after all.
A wild card in all of this is Israel. The more Israel complains, the easier it is for an agreement to get signed in Iran. However, the US and Iran both know, that at some point, Israel can decide when and if marginal cheating is too much and take military action. The Supreme Leader will keep a careful eye on Israel and insure that Israeli spying gets only the information he wants it to have to decide that nothing needs to be done - if that is possible.
The games nations play.