What a curious turn of events: from the very brink of a military intervention in Syria that might have precipitated a wider regional conflagration, we have moved to one of those rare "points of inflection" over Iran which seems fecund with potential possibilities, including a solution in Syria. Of course, such tipping points can tip either toward new solutions, or into a new phase of conflict.
Why should the possibility of US talks with Iran hold out such potential? It is because an earlier such point of inflection over Iran, a decade ago, tipped toward conflict, into the "axis of evil" versus the western-backed "moderates". It was the fierce push-back by Iran, Syria, Hezbollah and (at that time) Hamas against this attempt to impose a "hegemony of moderation" across the region, that caused regime change in Syria to become such a priority for the Sunni monarchies of the Gulf.