Barack Obama yesterday coupled a pledge that he was prepared to use military action if necessary to prevent Iran from acquiring nuclear weapons with a clear warning that "too much loose talk of war" had actually been helpful to Tehran.
On the eve of a crucial meeting today with the Israeli Prime Minister, Benjamin Netanyahu, the US President repeatedly emphasised his preference for a diplomatic solution, backed by sanctions. "For the sake of Israel's security, America's security and the peace and security of the world, now is not the time for bluster. Now is the time to let our increased pressure sink in, and to sustain the broad international coalition that we have built," he said in a speech to a conference organised by the American Israel Public Affairs Committee (Aipac) in Washington DC.
In doing so, and while forcefully warning that a nuclear-armed Iran ran completely counter to both Israel's and the US's security interests, Mr Obama did little to gloss over the issues at the heart of a disagreement between the US and Israel over their strategy towards Tehran's nuclear programme. Key to these differences are two closely-linked issues of timing. For Israel, the "red line" comes when Iran is capable of building a nuclear weapon. According to most Israeli readings, Iran is – thanks to its enrichment of uranium – not far off that point.
For the US administration, the red line comes significantly later, namely if and when Iran starts building, or at least decides to build, a nuclear weapon. This is why President Obama chose his words carefully when he spoke yesterday of his determination to prevent Iran from "acquiring a nuclear weapon", and this why he believes there is time for sanctions and diplomatic pressure. He will tell Mr Netanyahu that these offer a more "permanent" means of solving the problem than a bombing strike that would only set back a military nuclear programme for a few years at most, and might actually strengthen the Iranians' resolve to press ahead with it.
But what if the sanctions do not deter Iran, as Israel says it fears they may not? This is the second timing issue. For, according to the Israeli Defence Minister, Ehud Barak, Iran may soon enter a "zone of immunity", or the point at which its nuclear facilities, including its underground enrichment plant at Fordow, are beyond the reach of external attack, enabling Iran to complete a nuclear programme "without any effective intervention". Or, at least, without one by Israel, whose arsenal of "bunker-buster" bombs, though formidable, is simply not on the scale of the US military's.
What Israel has, by all accounts, been saying to Washington is this: "OK, if we accept your longer timetable and we wait to see whether the sanctions work, our window of opportunity for an effective military strike will almost certainly be passed. To allow that, we need in return an iron-clad commitment that the US will conduct such strikes if the sanctions fail to stop Iran building nuclear weapons. And that means more than simply saying yet again that ‘all options are on the table’. Only a concrete threat of military action is going to move the Iranians. Otherwise we may well have to go ahead on our own."
It remains to be seen whether Mr Netanyahu will be satisfied by the US President’s promise yesterday that "I will not hesitate to use force when it is necessary to defend the US and its interests" – interests which, he made clear, would be threatened by a nuclear armed Iran. Certainly, his warning against "loose talk of war" may be seen as a rebuke to some Israeli as well as US Republican politicians. And in publicly welcoming Mr Obama’s assurances last night, Mr Netanyahu pointedly singled out the endorsement of Israel’s "sovereign" right to defend itself as it saw fit.
To be sure, the President holds some cards. He knows Mr Netanyahu is a fairly risk-averse politician; that his ratings are strong enough not to need the severe electoral gamble of a war; that large sections of the Israeli military and intelligence establishment are opposed to a unilateral strike; and that the polls hardly indicate a popular clamour for war in Israel. And this is despite the relatively muted public debate within the country on the potential risks of starting one, from regional conflagration to a possible increase in the support for the Tehran regime by a currently restive Iranian population.
But in a presidential election year, Mr Netanyahu also has leverage. That these talks are being held on the margins of the Aipac conference is a reminder of the influence of that body (far more representative of Israel's government than it is of most American Jews) on US politics.
Mr Obama will be grateful for fulsome expressions of support by Israel's President Shimon Peres yesterday. But Mr Netanyahu's ability to play into the depiction of the US President by his Republican rivals as weak on Iran is not in doubt. Even if Mr Netanyahu is bluffing about a unilateral strike – and senior US officials seem far from confident that he is – Mr Obama may be hard put to resist the Israeli Prime Minister's efforts to force him into a more bellicose stance on Iran without suffering at least some political damage.
Nevertheless, for all of Mr Obama's entirely justifiable professions of how much he has done to foster America's relationship with Israel, yesterday's speech strongly suggests that Mr Netanyahu will not find the US President a pushover when he meets him today.