By Crispian Balmer
JERUSALEM (Reuters) - An upsurge in Israeli rhetoric warning of an imminent attack on Iran is aimed more at Washington than Tehran, and does not mean that the warplanes are firing up their engines.
A plethora of media reports over the past week has sent shivers through financial markets by suggesting that Israel might strike at Iran's nuclear facilities ahead of U.S. presidential elections in November.
However, senior Israeli officials say a final decision has not yet been taken, with government ministers still at loggerheads over the issue and the military hierarchy unhappy about the prospect of going it alone without full U.S. backing.
But if U.S. President Barack Obama does not lay out his red lines in the coming weeks, Israeli Prime Minister Benjamin Netanyahu may feel compelled to act, his inner circle says.
"Tehran doesn't see a U.S. strike on the horizon and is confident Washington will prevent Israel from attacking," said a senior Israeli official, who declined to be named.
"So Israel is looking for stronger public statements from Obama, either at the U.N. General Assembly or some other forum, that would change Iran's assessment," he added.
While Tehran says its nuclear program is peaceful, Western powers believe it is trying to produce an atomic bomb, and Israel views it as an existential threat to the Jewish state.
Netanyahu is set to travel to the General Assembly at the end of September and hopes to meet Obama to discuss the crisis.
He wants to secure three commitments: a pledge that the United States will attack if Iran does not back down; a tight deadline for negotiations with Tehran, which have so far proved fruitless; and a further tightening of the sanctions noose.
"Israel is telling President Obama that unless there is a change of tack, Israel will go it alone. I do believe that Netanyahu is serious about this," said Ehud Yaari, an Israel-based fellow at the Washington Institute for Near East Policy.
To a degree we have been here before.
In November 2011 there was a similar upsurge in alarmist chatter about the possibility of a unilateral Israeli strike. On that occasion it was a clear attempt to get world powers to ratchet up economic sanctions on Iran. It worked.
This time, Israel is telling the world the sanctions aren't proving effective and that only military force, or the very real threat of it, will dissuade Iran, as happened in 2003, when Tehran temporarily halted its nuclear work following the U.S. invasion of Iraq, fearing it would be next in the firing line.
"Iran will not engage seriously unless their situation is so bad that the alternative, giving up on their nuclear ambitions, will look better," said Emily Landau, a senior research associate at the Institute for National Security Studies.
But there is a fear in Israel that Netanyahu and his wily defense minister, Ehud Barak, have overplayed their hand.
U.S. officials have expressed incredulity at the chutzpah of the Israeli leadership in trying to corner Obama less than 100 days before his highly delicate re-election bid.
"I don't know what they are playing at," said a U.S. diplomat in Israel, adding: "A unilateral strike by Israel would be an act of folly."
In what was widely perceived in Israel as sharp slapdown for Netanyahu, U.S. General Martin Dempsey, the chairman of the Joint Chiefs of Staff, cautioned this week that any Israeli strike would not destroy Iran's nuclear program.
"I may not know about all of their capabilities, but I think that it's a fair characterization to say that they could delay but not destroy Iran's nuclear capabilities," he said.
However, Israel has never claimed its airforce, which lacks heavy bombers, could wipe out Iran's distant, numerous and well-fortified facilities. Instead, officials argue that buying time would be a good enough result.
"If we succeed in pushing off the nuclear program by six or eight or 10 years, there's a good chance that the (Iranian) regime will not survive," an unidentified top "decision maker", widely believed to be Barak, told Haaretz newspaper last Friday.
"So the objective is delay," he added.
Cynics say the objective could equally be to drag America into the war through a precipitous action, with Obama likely to face irresistible domestic pressure to leap to Israel's side.
A U.S. blogger published this week what he claimed were Israel's war plans leaked by an Israeli army officer.
The document promises "an unprecedented cyber-attack", a "barrage" of cruise missiles "to completely decapitate Iran's professional and command ranks" followed by an air attack by planes with special equipment to render them invisible.
Compelling doubts have been raised about the veracity of the document. A similar version appeared days earlier on an Israeli internet forum that said it was based on "Israeli publications, foreign media reports and the author's own imagination".
Nonetheless, the spin, leaks and anonymous briefings have spread anxiety, with queues building for gas masks at Israeli distribution centers and hedge funds laying bets on a potential spike in oil prices because of the war threat.
"All this exceeds anything I have ever seen before, and I have been around a long time," said Uri Dromi, a spokesman for former Prime Minister Yitzhak Rabin, who accused Netanyahu of reckless scare-mongering and damaging ties with Washington.
"It seems like he has forgotten who is the super power here," he said.
Certainly, when Israel undertook daring attacks in the past, there was no wild public debate beforehand - such as in 1981 when it destroyed a nuclear plant in Iraq and again in a 2007 raid on Syria, which apparently targeted a nascent reactor.
David Albright, founder of the Institute for Science and International Security, said he thought all the noise and fury could be an Israeli bid to shift world focus away from Syria and back to Iran. He did not see it as a prelude to a strike.
"No. I don't think so, because usually they would go very quiet," he said.
(Additional reporting by Tabassum Zakaria in Washington; Editing by Will Waterman)