Ronald Reagan used to scare the hell out of the Soviets. He was so ideological, so openly anti-Soviet, fanatical, senile and so extreme in the eyes of ... well, pretty much everyone except Jerry Falwell. One Genesis video (jam-packed with cultural references now recherché) suggested that Reagan was, as President, senile enough to start nuclear war by accident.
From the point of view of nuclear deterrence this was ideal. A president who could be counted upon to order a nuclear strike, or one who could be counted on to refrain from ordering one, could be out manoeuvred. A president who was apparently irrational could not be.
Bibi Netanyahu apparently irritates his G20 colleagues. That's not going to lose Netanyahu any votes at home, and from a deterrence point of view it's very useful. An Israeli PM with no Nobel Peace Prizes around his neck is credible as a potential button-pusher. This is useful because he's pitted against a foaming little pit bull like Ahmadinejad, apparently held back by the firm hand of Ali Khamenei.
Much tosh has been written this week on the subject of potential Israeli attack against Iran. It's not tosh because it's inaccurate (though sometimes it is - the CEP of a Jericho is 1km? With a GPS-guided re-entry vehicle? Where'd Reuters get that -- Wikipedia?). It's tosh because it confuses capability and intent, ends and means.
Israel has to deter Iranian development of nuclear weapons, not only because the Israelis can ill-afford to trust their survival to a regime that talks about wiping Israel off the face of the Earth, but because a nuclear-armed Iran will likely lead to a nuclear-armed Egypt and a nuclear-armed Saudi Arabia; and Israel would have a hard time sleeping comfortably with either.
Forever is a long time, and no realistic action against Iran would rob the country of nuclear capability until the end of all days. Any military action conceived against Iran would have to succeed in reliably setting back Iran's development of nuclear weapons a long way, perhaps 10 years. Anything less would not be worth the bombardment from Hizballah that Israel would have to sustain, or the costly pre-emptive war Israel would have to fight against Hizballah to prevent the rocketing.
An effective attack against Iran would require destroying a great deal of dispersed and very well-protected equipment as well as all or nearly all of Iran's store of nuclear materials. Any attack that did not achieve this would be worthless to Israel and a boon to the Iranian regime.
Remember that Iran withstood Iraqi missiles launched at their city centres and are confident of their ability to sustain any amount of conventional pounding from the Israelis. Withstanding massive missile attack is a proven Iranian strength. A few holes blasted in the Iranian countryside? No problem.
Chucking sea-launched Popeye Turbo cruise missiles with conventional warheads in the general direction of Iranian nuclear facilities isn't going to do it. It's like trying to stop a bear with a handgun: "If you shoot him you'll just make him mad". Iran has a population of more than 77 million: more than France and only slightly fewer than Germany, and its land area is more than twice that of France or, for that matter, Afghanistan. Have intelligence services located all facilities? Could any attack be certain of completely destroying all facilities? If not, there's no point in conducting the operation. Uncertainty, inevitable in real operations, makes an attack a poor bet for the Israeli cabinet.
Any attack would have to be very, very precise, thorough and very, very powerful.
What's important in deterring Iran is that Israel is capable of conducting powerful covert operations, special forces operations or precise air operations to destroy elements of Iran's nuclear capability. This shapes Iran's nuclear ambitions. If they get too close to an operational capability, they could force the Israelis into an attack that, however well- or ill-judged, could rob them of such an effective tool of confrontation. Uncertainty makes an open declaration or demonstration of a deployable capability a poor bet for Iran's Supreme Leader.
For Iran, confrontation with Israel is an end in itself. Actually destroying Israel isn't required. Iranian policy requirements are satisfied by making it clear that Iran has nuclear capability and that Iran is pointing it directly at the Little Satan. Launching a nuclear weapon brings the prospect of failure. Failure to launch, interception at boost phase by Israeli weapons, interception by Israeli theatre air defence weapons or failure to detonate would all turn the success of confrontation into a colossal waste of effort. Also, it would demand Israeli nuclear retaliation. With most of Iran's huge population concentrated in cities, a nuclear countervalue second strike from Israeli submarines would be devastating.
Netanyahu has to talk tough and appear dangerous and likely to order a strike, both for his domestic audience and for his Iranian audience. Khamenei has to keep him talking tough and confronting. Neither of them can afford to be conciliatory. It's a bit of theatre, but a bit of serious theatre. Waving weapons around is dangerous, and nuclear brinkmanship is no joke. What the rest of us mustn't forget, however, is that Iran would face disaster if it launched a first strike against Israel and Israel would gain nothing from a partially-successful attack on Iran.