It has become an article of faith among Israeli leaders and their neoconservative partners in Washington that the only way Iran can be persuaded to back down in the nuclear standoff is if Tehran believes it's in real danger of being bombed. Hence the relentless war drums pounded by Prime Minister Benjamin Netanyahu and Defence Minister Ehud Barak, despite the obvious misgivings of the Obama administration.

Mr Barak last week told a TV interviewer that Israel didn't want to start a war with Iran, but that Iran may leave it no choice (although he offered no benchmarks for this assessment). Mr Netanyahu, meanwhile, offered a somewhat clumsy parable about Israel's founder, David Ben Gurion, making decisions that went against the best advice he was getting, and in so doing ensuring Israel's creation. The subtext: just because everyone's telling me bombing Iran is a really stupid idea doesn't mean I won't do it; history will absolve me.

But the dark warnings of Mr Netanyahu and Mr Barak notwithstanding, it's obvious that Iran isn't expecting to be bombed any time soon, much less planning to back down on its nuclear programme. On the contrary, Tehran remains as defiant as ever, even allowing itself such potentially reckless luxuries as playing out domestic political rivalries by sending militiamen to trash the British embassy. (That appears to have been the work of rivals to President Mahmoud Ahmadinejad). Iran also raised the ante with the United States, announcing it had brought down a surveillance drone that had crossed into Iranian territory from Afghanistan - signalling to its own public that Iran was under attack by the US and potentially raising a public clamour for retaliation. (By contrast, Iran had largely avoided acknowledging that recent explosions at a missile site and uranium conversion plant may have been the work of saboteurs, perhaps to avoid raising pressure to strike back).

On the whole, though, Iran's regime doesn't seem to be shrinking from confrontation with western powers and Israel. It may be strengthened politically by that confrontation, and it has reason to doubt any attack is imminent. Key figures in the security establishment in both the US and Israel are certainly pouring cold water on the "military option" bandied about by politicians and pundits.

The US Defence Secretary Leon Panetta last week reiterated the Pentagon view that air strikes on Iranian nuclear facilities would, at best, delay Iran's progress by one to two years but would set off a conflagration dangerous for regional stability and the global economy. And that's if the US did the job: the Israelis routinely threaten to act alone if Washington is unwilling, but there's reason to doubt how effectively a country 1,200 kilometres away could stage the hundreds of sorties over many days required to suppress Iran's defences and destroy known nuclear facilities in at least six different locations hundreds of kilometres apart.

Mr Panetta's predecessor at the Pentagon, Robert Gates, has also warned that bombing would push Iran's leaders to ignore Ayatollah Ali Khamenei's 2005 fatwa declaring the production or use of nuclear weapons "un-Islamic" and build nuclear weapons - a decision not yet made, according to western intelligence agencies. And they would do so in secret, having kicked out the IAEA monitors who currently have Iran's facilities under surveillance, and serve as an early warning system on any diversion of nuclear materials for possible weapons programmes.

The historian Avner Cohen argues that the lesson of Israel's oft-touted bombing of Iraq's Osirak reactor in 1981 has been misunderstood: although Saddam Hussein clearly wanted nuclear weapons at some point, Osirak had been under IAEA monitoring and had not been set up in a way that would facilitate the production of weapons from plutonium extracted from spent fuel rods. But within three months of the reactor's destruction, Baghdad had decided to launch a clandestine nuclear weapons programme using centrifuges to enrich uranium in secret.

This programme went undetected until Saddam lost the 1991 Gulf War. And the clandestine programme had got a lot closer to being able to produce weapons than anyone suspected. "This means that the bombing success was a Pyrrhic victory," Prof Cohen argues. "The fact that Osirak was left in ruins apparently contributed to the stealthy progress of Iraq's subsequent nuclear effort."

Prof Cohen warned that military action against Iran would be more likely to push Iran to build and test nuclear weapons than to stop it: "Such action would obligate Iran to abandon the Nuclear Nonproliferation Treaty (NPT), heighten its determination to pursue accelerated nuclear weapons development, and most important, would create a situation of a declared and deployed nuclear Iran, in the Pakistani style."

Another Israeli weighing in last week against the folly of launching a war against Iran was former Mossad chief Meir Dagan, who warned Israelis that their leaders were considering recklessly plunging Israel into a war of choice from which it could not easily extract itself, and for which it could pay a heavy price.

"I think that engaging, with open eyes, in a regional war is warranted only when we are under attack or when the sword is already cutting against our live flesh," Gen Dagan warned on Israeli TV. The problem, of course, is that in the current scenario, even if direct military action is avoided, the alternative pursued by Iran's adversaries is covert warfare and the push for crippling sanctions. Those options, should they hit a nerve, also run the risk of escalating into full-blown confrontation. Despite the domestic political climate in both Washington and Tehran precluding open diplomacy between the two sides, regional stability might depend on someone - perhaps Turkey or Qatar? - urgently stepping up to provide an effective back channel.