Iran deal may not herald rapid changes

The lifting of crippling international sanctions linked to Iran's nuclear program and the flurry of diplomacy that led to the release of Americans held by Tehran suggests a new era could be dawning. But anyone hoping for rapid change is likely to be disappointed.

President Hassan Rouhani and his team have plenty to celebrate now that nuclear sanctions have been removed. The moderate leader promised to boost Iran's struggling economy and improve its relations with the wider world during his 2013 campaign. The nuclear deal achieves both aims.

It will take time for the economic benefits to trickle down to ordinary Iranians, but the goodwill from the deal could translate into electoral gains for moderate and reformist candidates in parliamentary elections late next month. For all the conversations US Secretary of State John Kerry and Zarif have had over the past few years, the fact remains that they represent countries that do not have formal diplomatic relations. Still, the two diplomats have forged a working relationship that can at times bear fruit.

Months of negotiations resulted in the release of four Iranian-Americans from prison, including Washington Post journalist Jason Rezaian, in exchange for seven Iranians held in the US, six of them also dual nationals. And rapid-fire diplomacy managed to get 10 US Navy sailors and their boats released from Iranian custody in less than 24 hours last week - an unthinkably quick turnaround compared to past cases where foreigners found themselves in Iranian territory. But there are limits.

Iranian-American businessman Siamak Namazi, who is believed to be detained in Iran, was not part of this weekend's prisoner swap. Also still missing is former FBI agent Robert Levinson.

Iran meanwhile remains a staunch backer of Syrian President Bashar Assad, putting it at odds with the US and Sunni Arab powers including Saudi Arabia. In Yemen, a US-supported, Saudi-led coalition is fighting to roll back gains by Iranian-backed Shia rebels. And mistrust runs deep on both sides.