Israel’s new focus on the Iran nuclear deal

The interim nuclear agreement with Iran, touted by its proponents as a "historic deal", has been described as a "historic mistake" by Israel's prime minister, Binyamin Netanyahu. How will Israel react in the months ahead? The answer is to be found in the struggle to shape the endgame deal.

The six-month deal is a mixed bag. On the positive side it stems the tide of Iranian nuclearisation by setting its clock slightly back, temporarily capping Iran's nuclear facilities, array of centrifuges and stockpile of low-enriched uranium, and improving the monitoring regime. On the other hand, Iranian enrichment has been accepted as part of the endgame; the clock in the uranium and plutonium tracks continues to tick, albeit at a slower pace; Iran's stockpile of low-enriched uranium (enough for at least five bombs) remains intact; Iranian concessions are all reversible; and International Atomic Energy Agency concerns about military dimensions have not been addressed. It remains to be seen whether the sanctions relief will entice Iran to make further concessions in the final deal or will erode the sanctions regime as a whole.

While putting the brakes on Iran's nuclear programme is better than allowing it to accelerate or triggering a confrontation, Tehran is far too close to a critical breakout capacity for this to be an acceptable situation in the long term. Israel's sight is therefore fixed on the endgame. There is widespread scepticism in Israel – shared by many of its Arab neighbours – that the US and its European allies possess sufficient resolve in the face of Iran's determination to establish itself as a threshold nuclear-armed state.

For Israel, the endgame must deny Iran the capacity to swiftly break out a bomb before it can be stopped. Iran can already produce one bomb's worth of military grade uranium within weeks. If it commissions its Arak heavy water plutonium reactor, which could take around a year, its route to weapons-grade plutonium cannot be stopped by outside intervention. Israel would like the clock set back on breakout capacity to a weapon from months to years. For this, Iran must be denied some of the core capabilities it has or is pursuing, including the heavy water reactor. The International Atomic Energy Agency's open files on weaponisation research must also be closed and intrusive monitoring applied.

Israel will be pleasantly surprised if the six-nation group known as the P5+1 produces such a deal. Senior Israeli officials question whether the group can agree among itself, and fear its eagerness for a deal weakens its bargaining position. They ask: if the pressure of sanctions could not get Iran to tackle the endgame now, why would relaxed sanctions produce the desired result in six months? Added to this are concerns that the legitimacy bestowed on Iran will give it a freer hand to advance its other destabilising regional policies, while the US seeks to focus its attention elsewhere.

In this context, the scathing Israeli criticism of the agreement now gives way to a cooler-headed diplomatic campaign to influence the endgame deal. Israel wants its US and European allies to define and stick to clear goals; to enforce remaining sanctions; and to clarify to Iran the consequences of non-compliance with the interim deal or averting a reasonable comprehensive deal.

Faced with possible additional sanctions and a credible military option, Iran is more likely to concede without the need for military action. In both respects, Israel has the potential to play an active role. It could encourage additional sanctions in the US Congress conditional on Iran's behaviour, while also making clear that its own military option is on the table.

For the next six months Israel's goal will be to seek an acceptable deal, rather than scupper the process. But a deal that does not meet its basic expectations, no deal at all, or an endlessly strung-out process while Iran advances its programme, will place its decision-makers back on the horns of a dilemma: whether or not to intervene to avert what it considers the most serious threat to its national security.