Hassan Rouhani's stunning and sweeping victory in the Iranian presidential election is already generating much debate among expert Iran-watchers about how to interpret this outcome. There are different views, for example, on what inference should be drawn regarding the posture of Supreme Leader Khamenei toward the election. Was this outcome one that the leader might have anticipated and is part of a skillful management of contending factions, or does the election result instead indicate that the leader's control of Iranian politics is less than was often surmised? There also are different views on what role sanctions-induced economic strain may have had on the election. These are genuine questions on which objective and well-informed observers can disagree. Not genuine is the spin from some other fast-off-the-mark commentators who are endeavoring to deny any significance to Rouhani's victory and to portray the Iranian regime as nothing but the same old recalcitrant adversary—a spin motivated by opposition to reaching agreements with Iran and the favoring of confrontation and even war with it.

Useful implications for policy toward Iran can be drawn without resolving all these analytical questions, even the genuine ones. Sometimes a particular course of action is the best course under any of several different interpretations of exactly what is going on in another nation's capital. This is one of those instances. In particular, there are clear implications for approaching the next stage of negotiations on, and policy toward, Iran's nuclear program—which, for better or for worse, is the subject dominating discussion of relations with the Islamic Republic.

One thing that the Iranian election would have changed no matter what the outcome on election day is that we soon will not have Mahmoud Ahmadinejad to kick around any more. The end of his distracting and annoying presence can only be to the good. Perhaps at least a little more serious attention will be devoted in the United States to policy and diplomacy when there is a little less energy allocated to expressing outrage over the outgoing Iranian president's mistranslated quotes about wiping maps and his other intentionally inflammatory rhetoric.

Rouhani's win brings to Iran's presidency the candidate who was least associated with attributes of the Iranian regime that the West finds most offensive. While one must always be careful in affixing labels to individual leaders and factions in Iranian politics, the pre-election characterization of Rouhani as the most moderate of the six candidates remaining in the race until election day is accurate. The election result also is a vote in favor of flexibility and going the extra mile to reach agreement in the nuclear negotiations. In this regard one of the significant aspects of the result is not only how well Rouhani did but also how bad the result was for one of the other candidates, Saeed Jalili, the current nuclear negotiator. Conduct of the negotiations was an issue in the campaign. Yet another candidate, former foreign minister Ali Akbar Velayati (who possibly could become foreign minister again under Rouhani) pointedly criticized Jalili in one of the candidates' debates for apparently expecting too much from the other side while offering little in return. Jalili, who before the election had been dubbed the supreme leader's man and was considered by some the favorite, finished a far-behind third place, with less than a quarter as many votes as Rouhani.

There clearly is an opportunity for diplomatic progress. More to the point, there is a challenge, to the United States and its P5+1 partners in the nuclear negotiations, to do their part to make such progress possible. This is true no matter which of several possible interpretations of the details of politics in Iran is valid. Whether the supreme leader is stage-managing a process that leads to an outcome he has always welcomed, or is being pushed toward that outcome by forces and sentiments he cannot control, the implication for western policy is the same. We should spend less time trying to interpret what's happening on the other side and more time thinking about how the other side interprets our policies. This is important because a lack of Iranian confidence in the West's desire and willingness to make a deal and to stick with it almost certainly has been one of the impediments to progress in the nuclear negotiations.

Rouhani's election presents the United States and its partners with a test—of our intentions and seriousness about reaching an agreement. Failure of the test will confirm suspicions in Tehran that we do not want a deal and instead are stringing along negotiations while waiting for the sanctions to wreak more damage. Passage of the test will require placing on the table a proposal that, in return for the desired restrictions on Iran's nuclear activities, incorporates significant relief from economic sanctions and at least tacit acceptance of a continued peaceful Iranian nuclear program, to include low-level enrichment of uranium. The sad fact is that the criticism Velayati leveled at Jalili's negotiating approach could be applied just as easily to the approach of the P5+1, which so far have coupled their demands about the nuclear program with sanctions relief that is only a pittance compared to the large and ever-growing array of sanctions applied to Iran. Passage of the test also means not making any proposal an ultimatum that is coupled with threats of military force, which only feed Iranian suspicions that for the West the negotiations are a box-checking prelude to war and regime change.

The Iranian electorate has in effect said to the United States and its Western partners, “We've done all we can. Among the options that the Guardian Council gave us, we have chosen the one that offers to get us closest to accommodation, agreement and understanding with the West. Your move, America.”