Iran-US 'rapprochement' challenges Israel's Netanyahu
The next few days could be crucial for the Israeli Prime Minister Benjamin Netanyahu and for the future course of US-Israel relations.
The diplomatic rapprochement between the United States and Iran - symbolised by the telephone conversation between President Barack Obama and his Iranian counterpart Hassan Rouhani - has provoked a wave of euphoria among commentators and even some diplomats.
The hope is that a deal to resolve the long-running dispute over Iran's nuclear programme might be achieved within a year.
In the United States this week, Prime Minister Netanyahu risks appearing like a ghost at the feast; a travelling salesman whose wares have lost their appeal; a man whose warnings against Iranian perfidy seem out of tune with the moment.
Israel seems to have been caught unawares by the apparent success of Iran's charm offensive towards the West. Official briefings initially sought to take a cautious stance. Israel, they said, had the most to gain from a negotiated settlement that halted any Iranian progress towards a bomb. "Distrust and verify" might have been the watchwords.
This, they argued, was a regime that could not be trusted and whose negative influence in the region went way beyond its nuclear activities.
So test out the Iranian overtures by all means, was the message from Israel's professional diplomats, but do so with a clear head and no wishful thinking.
Israel's political leadership, however, put a rather different accent on things.
Prime Minister Netanyahu instructed Israeli diplomats to absent themselves from the UN chamber when President Rouhani was speaking. Iranian comments moderating their long-standing denial of the Holocaust perpetrated against the Jews by the Nazis during World War II won Tehran few brownie points in Israel.
And on the eve of Mr Netanyahu's meeting with President Obama, his government disclosed that its intelligence services had unmasked an Iranian espionage operation. A coincidence of timing? I doubt it.
The message that Mr Netanyahu will take to the White House and to the podium of the UN is that this is the same old Iran. Washington and its allies should not be taken in.
Well Mr Netanyahu may or may not be right. Euphoria and wishing that things will turn out for the best is not a terribly useful commodity in international relations.
The problem for Mr Netanyahu is that scepticism may be healthy, negativity is not.
Israel has long argued for economic sanctions to be strengthened against Tehran. The purpose of sanctions was to bring Iran to the negotiating table.
Now this appears to be happening Israel cannot simply dismiss it all as an Iranian subterfuge.
As the veteran Israeli strategic commentator Amos Yadlin notes, what matters now is the "content" of any agreement between Iran and the West.
The goal, he says, is "a good agreement that can credibly neutralise the danger of an Iranian bomb", rather than "a bad agreement that will allow Iran to attain a possibility to dash to a nuclear bomb" at some point in the future.
The coming weeks and months are going to prove a strong test of the relationship between Mr Netanyahu and Mr Obama. The Israeli Prime Minister may be tempted to dig in his heels; to count on support among Israel's friends on Capitol Hill to bring pressure to bear on the White House.
Mr Obama has to convince Mr Netanyahu that he has Israel's back; that a good deal for Washington will be a good deal for Israel too.
Israel is not the only country in the region which may be concerned at the developing diplomatic opening between the US and Tehran. Washington's key Arab allies - not least the Saudis - are similarly uneasy.
The real test is going to be to determine if the Iranians are sincere.
Can President Rouhani deliver a deal despite domestic opposition from conservative circles? If he can't then Mr Netanyahu's scepticism may be justified. But Israel could find itself in a difficult position if it is perceived to be trying to torpedo any deal from the outset.