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Not so fast: Ex-Israeli intelligence chief speaks out on Iran strikes

TEL AVIV, Israel - A cavernous space has been carved out of the ground two floors below street level.

Overhead, it's another scorching summer's day in Tel Aviv, Israel's biggest and busiest city.

Down here, under the neon lights, a massive, blast proof steel door swings open to reveal a hidden realm.

Locked away from today's bright sunlight, it feels like a gloomy and surreal underworld.

Asaf Zamir, deputy mayor of Tel Aviv, shows off one of the city's newest bomb-shelters.
Asaf Zamir, deputy mayor of Tel Aviv, shows off one of the city's newest bomb-shelters.NBC News

However, it is all too real.

"This is one our newest bomb-shelters," Asaf Zamir, deputy mayor of the city told me as he showed off, with no little pride, the facilities. "Here there's space for 400 people."

There are, he said, 241 public shelters in the city. This, like another 110, are protection against the threat of chemical attack.

"There's air conditioning, toilets and water.  And two showers.  I think the (lines) might be long," Zamir joked.

But this is deadly serious: In the event of war, Tel Aviv would be high on the list of targets of Israel's enemies.

Israeli rhetoric on Iran strike heats up 

While Israel is a country that is permanently on a war footing, there is an added sense of urgency here this summer. And in many minds, a sense of inevitability about war with Iran amid Tehran's continued refusal to be more transparent about its nuclear activity and growing speculation that Israel will bomb in response.   

An intense debate on a possible war has played out, both on and off the record, in Israel's news media.

Wade through the oceans of words written and spoken and a single, simple narrative emerges time and again.

Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak are all but convinced that the only way to stop Iran's progress towards nuclear weapons is to launch air-strikes on their research centers.

Against them are ranged the top ranks of Israel's defense and intelligence establishment.  And their voices urge caution.

Among them, Maj. Gen. Aharon Zeevi Farkash, until 2006, chief of military intelligence.

Now in retirement, he remains, it seems, in touch with the top level debate raging behind closed doors.

Zeevi Farkash granted us a rare interview. He said he chose to speak out because he was concerned that Israel might be about to make a costly mistake.

"I worry about the day after an Israeli strike," he tells me. "Hezbollah has 60,000 rockets, Hamas 30 to 40,000 rockets.  And I am afraid that this would be a wonderful reason for Bashar Assad to launch his missiles at us."

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He predicts that unilateral military action by Israel would simply unite the rival factions crowding round the rule of President Mahmoud Ahmadinejad.

"In any case, I believe it is impossible to destroy all the infrastructure and targets connected with the Iranian nuclear plan. It's impossible. I'm not even sure we know everything that we need to know," he said.

Read more work by John Ray on NBC News' British partner ITV News

"Because of that it is my opinion to try not to do this alone," he added. 

Instead he said sanctions and diplomacy, backed by the threat of U.S.-led military action, should be given longer to work.

"Finally I think Western leaders realize a nuclear Iran is the number one challenge facing the world .... Therefore with this coalition I can see results. I strongly believe we have the time, maybe eight or nine months," Zeevi Farkash said.

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Neither Netanyahu nor Barak share his confidence in sanctions, or his assessment of the available timescale.

Zeevi Farkash said they will want to make a decision on airstrikes "in the next two months."

I asked him if political leaders can push through military action, even in defiance of the advice coming from the top brass.

"I have been in these intimate meetings making the tough decisions," he said. "I have never seen that happen in the past so I hope it will not happen in the future."

Back in the Tel Aviv bunker, deputy mayor Zamir told me the city was as ready as it ever can be for war.

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"All this talk (of war) in the papers has created a sense of panic among people," he said.

I asked him if he is confident Tel Aviv will survive, whatever comes.

He paused for several seconds.

"I'm optimistic," he replied.

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