As foreign ministers embraced in Geneva after securing the deal over Iran’s nuclear programme, a sense of dismay and abandonment descended on Gulf capitals. Initial reactions ranged from conspiracy-laden panic from pundits to uneasy silence from Saudi Arabia, and a guarded welcome from the United Arab Emirates.

In the US, where the focus is on rapprochement with Tehran, some brush this aside with a disdainful “So what?”. But it would be an error to dismiss Gulf states’ anxiety. They may be unable to oppose a nuclear deal but they are crucial to any new security arrangement.

In truth, Sunday’s accord is a net security gain. It lengthens Iran’s nuclear weapon timeline, paving the way for a comprehensive final agreement.

Gulf officials complain that it does not address Tehran’s troublesome behaviour. That is unfair, as local security was never the focus of the talks. It is also welcome: the Geneva set-up was simply not the right forum. The Gulf states should be demanding to be involved directly in regional security discussions rather than outsourcing to outside powers.

Gulf concerns about Iran are not baseless. The nuclear programme was accelerated under the pragmatic Akbar Hashemi Rafsanjani and the reformist Mohammad Khatami. Gulf officials who worked with both men felt cheated; hardline Mahmoud Ahmadi-Nejad at least seemed a more faithful expression of the Islamic Republic’s ethos. President Hassan Rouhani may fare better both in Tehran and with the Gulf states, thanks to his insider status and now his diplomatic success.

Another telling source of insecurity is the questionable assumption that western hearts, minds and perhaps even pockets are in Tehran rather than in Gulf capitals. Given a chance, westerners would eventually flock north and turn Iran into a strategic partner at their expense.

A more immediate concern is whether Sunday’s deal opens the way for a quid pro quo on regional security that subordinates Gulf interests to Iranian ones. Already, some suspect that Washington made promises to Iran during secret talks in Oman. Will a US president keen to “pivot” away from the Middle East excuse Tehran’s behaviour and provocations in order to protect his sole diplomatic achievement?

In Gulf eyes, President Barack Obama has shown himself as naive on Iran (and Egypt), and cynical on Syria. The concern is that US policy has rested on a deal with Iran and the anticipation that this would help Mr Rouhani reorient Iranian policy.

Take Syria. A strike against the Assad regime could have jeopardised Mr Obama’s secret diplomacy. That it did not happen kept the Iran track alive. Paranoid, conspiracy theory? Not to some Gulf analysts.

No issue will determine the regional balance more than Syria. The Gulf states, led by Saudi Arabia, want to bring about President Bashar al-Assad’s downfall, but a rebel victory will not happen under current circumstances. While the Gulf states provide money and weapons, Iran offers the Assad regime the experience, expertise and strategic patience that worked so well on other battlefields.

In response, the Gulf states must think politically. The nuclear deal is intended to strengthen Mr Rouhani’s hand against the hardliners who run Iran’s Syria policy. So, instead of resisting Iranian participation in the Geneva talks scheduled for January, the Gulf states should make explicit, unconditional endorsement of the June 2012 Geneva statement that outlines a transition from Assad rule the test of Mr Rouhani’s credibility – and by extension that of the US.

Making bombastic statements about charting an autonomous foreign policy and veering away from the US is neither smart nor constructive. Even Saudi Arabia, which has been particularly vocal, lacks options, allies and experience for what would be a costly and risky all-out campaign to check Iran.

However clumsy, the US remains the sole viable security guarantor of the Gulf states. Protestations and empty threats from the sidelines make them look more insecure than they should be. Rather, they should now focus on shaping the final status agreement by broadening its scope and articulating a clear regional security agenda.

This means thinking about what a normal relationship with a normalised Iran should look like – from foreign military basing and maritime arrangements to joint economic and infrastructure projects. Oman, Qatar and even the UAE can help smooth the way.

The Gulf states have successfully internationalised their security, gaining leverage and allies. It is time to deploy both in mature and judicious ways.

The writer is senior fellow for Middle East Security at the International Institute for Strategic Studies

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