Time for a quiz question. Last week, who said Binyamin Netanyahu and Ehud Barak – Israel's prime minister and defence minister – "are misleading the public on the Iran issue" and making decisions "based on messianic feelings"? Was it (a) Iran's president, Mahmoud Ahmadinejad; (b) the Stop the War Coalition president, Tony Benn; or (c) the former Israeli spymaster Yuval Diskin?

It was (c). At a public meeting on Friday Diskin, former head of Shin Bet (Israel's MI5), described Netanyahu and Barak as "not fit to hold the steering wheel of power". He went on: "I have observed them from up close … They are not people who I, on a personal level, trust to lead Israel to an event on that scale and carry it off … They tell the public that if Israel acts, Iran won't have a nuclear bomb. This is misleading. Actually, many experts say that an Israeli attack would accelerate the Iranian nuclear race."

Illustration by Andrzej Krauze

Diskin joins a long list of eminent members of the Israeli security establishment who have publicly voiced criticism of, and opposition to, their government's ultra-hawkish line on Iran. In fact, his astonishing attack on his former bosses came just 48 hours after the head of Israel's military, Lieutenant General Benny Gantz, declared that the Iranian leadership had not yet made a decision to build nuclear weapons, that it was unlikely to go this "extra mile", and was composed of "very rational people". "Decisions must be made carefully out of historic responsibility but without hysteria," added Gantz in a not-too-subtle dig at his political masters.

Last month, in an unprecedented move, Meir Dagan, the former head of the Mossad – Israel's foreign intelligence service – took to the airwaves in the US, using an interview with CBS to tell his American audience how a war with Iran would be "devastating" for Israelis because it would "ignite, at least from my point of view, a regional war". (He had earlier described an Israeli attack on Iran as "the stupidest idea I've ever heard".)

Meanwhile, Dagan's predecessor, Efraim Halevy, has said "it is not in the power of Iran to destroy the state of Israel", and that "the growing Haredi radicalisation poses a bigger risk than Ahmadinejad". Then there is the current head of the Mossad, Tamir Pardo, who is said to have told an audience of Israeli diplomats in December that a nuclear-armed Iran would not constitute an "existential threat" to Israel.

But this isn't just about spymasters or generals. There is no consensus favouring military action against Iran within Israel's political establishment either. Recent media reports have suggested Netanyahu and Barak are isolated within their own cabinet; Daniel Ben-Simon, a Labour party member of the Israeli parliament, has called them "a two-man show" – or, as a recent headline in the New York Times put it, "Two Israeli leaders make the Iran issue their own".

Shaul Mofaz, the opposition leader – of the Kadima party and a former head of the Israeli army – has objected to Netanyahu's obsession with attacking Iran. "The greatest threat to the state of Israel is not nuclear Iran," Mofaz said in an interview earlier this month, citing the unresolved conflict with the Palestinians as a much more pressing issue. The Israeli president, Shimon Peres, told CNN in November that he preferred a "moral" attack on Iran, not a military one.

Oh, and guess what? The Israeli public is far from gung-ho. According to a poll released last month by the Israeli Democracy Institute and Tel Aviv University, 63% of Israelis oppose a unilateral Israeli strike on Iranian nuclear facilities. An earlier poll, for the University of Maryland in February, revealed only a fifth of Israelis favoured a strike on Iran without the support of the United States.

There is an important lesson here for the west's hawks and doves alike. The hawks in the Commons and Congress who invoke Israel's national security as the chief justification for a pre-emptive attack on Iran are ignoring the expert opinions of Israel's own military and intelligence chiefs, both past and present. Meanwhile, the doves who take to the streets with anti-war placards that blame the Jewish state for exaggerating the threat from Iran should consider replacing the word "Israel" with "Netanyahu".

It is the cynical and belligerent "Bibi" who takes every opportunity to fear-monger about a Nazi-like threat from Iran. In a speech this month to mark the Holocaust, he proclaimed: "People who refuse to see the Iranian threat have learned nothing from the Shoah [Holocaust]." And last month in the US, he compared bombing Iran to bombing Auschwitz.

But Netanyahu isn't Israel – a nation of 7.8 million people, including 1.6 million Arabs. Those of us opposed to another catastrophic conflict in the Middle East should not allow his alarmist and messianic rhetoric to drown out the voices of Israel's doves: those critics of military action, who, ironically, are far more numerous and outspoken than the doves on Capitol Hill or in Westminster, and have far better credentials.

Just as it is wrong to reduce Iran to Ahmadinejad, or the US to George Bush, it is wrong, and counter-productive, to reduce Israel to Netanyahu. Its ordinary citizens don't want war with Iran, and the country's top spooks and soldiers are queueing up to tell us why.

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