But while every country in the region publicly backs the fight against ISIL, the grand diplomatic success announced on Tuesday is a bridge too far for Israel and Saudi Arabia, underlining the fact that they can no longer count on the U.S. to marginalize Iran at every turn. “The U.S. and Iran aren’t about to start trusting one other, much less become fast friends,” Ian Bremmer, chairman of the Eurasia Group consultancy, said in a Facebook post on Tuesday. “But in the world created by the deal, Iran starts to matter much more than Saudi Arabia and other old-guard U.S. allies.”
At the same time, there are fears that Iran will assert itself more forcefully in the region once sanctions are lifted. In Syria, Iraq and Yemen, Tehran has either backed or been accused of backing various Shia groups against Sunni factions. The region’s Sunni powers, especially Riyadh, are fearful that this will only become more common without the threat of sanctions. Bremmer said that could very well be the case: “As the U.S. and Europe look to reduce their presence in the region, the escalation of proxy wars between Saudi Arabia and Iran will heighten the risk of direct conflict."
The balance of power "will tip toward Iran," Bremmer said, in large part because sanctions relief will provide a major boost to the Iranian economy. In addition to the stream of investment that is expected to flow in to Iran, a highly educated nation of nearly 80 million people, the country's oil will find its way back on the international market and cut directly into Saudi exports. Though Obama has long argued that economic relief will encourage Iran to become “a more conservative power, one that could help us find solution to Syria and Iraq,” Bitar explains, Iran skeptics say a revived economy will only fuel the Iranian war machine.
Still, some analysts caution against alarmism. Adnan Tabatabai, an Iran expert and the co-founder of the Center for Applied Research in Partnership with the Orient, noted that Iran's President Hassan Rouhani has made painful, politically unpopular concessions to Iran's sworn enemy, the U.S., and will be under intense pressure domestically to prove that the deal was worth it. “The government is very well aware that it has to improve the living conditions of ordinary people. The stability of the country depends on this,” Tabatabai said. “I really think this potential financial boost will be used for economic growth rather than more expansionist activity.”
And despite the rhetoric of Israel’s leadership — who remind Israelis that Iran's Supreme Leader often threatens to destroy Israel — there are believed to be many in the Israeli military and intelligence establishment who favor the nuclear deal as a way to contain Iran's nuclear threat. As Obama has repeatedly emphasized amid his unprecedented overtures to Tehran, U.S. support for Israel remains steadfast.
The more worrying tension may be between Iran and Saudi Arabia. Mansour al-Marzouki, an independent Saudi researcher, argued that Riyadh's sense of abandonment by Washington may compel it to forge stronger alliances with fellow Sunni states. In fact, those gears have long since been set in motion, in the midst of Obama’s perceived retrenchment from the region — signaled by the withdrawal of U.S. troops from Iraq (before sending more “trainers” back to help fight ISIL) and his subsequent refusal to strike the Tehran-backed regime of Bashar al-Assad in Syria, as the Gulf powers had requested.
According to Nasser bin Ghaith, an Emirati economist and researcher at the Abu Dhabi-branch of Paris-Sorbonne University, the potential of a Sunni Arab military alliance — once considered futile given the region’s internecine rivalries — has been demonstrated by the Saudi-led military campaign against the Shia Houthi rebels in Yemen, who are said to be backed by Iran. This cooperation, bin Ghaith told Al Jazeera, “has shown that these states can not only work together on regional threats and initiate major actions, but also have the potential to become a major regional player capable of countering U.S.-backed Iranian hegemony.”