Israel worried about Iran nuclear 'immunity zone'

Telegraph:

Reviving Western concerns that his government is still contemplating unilateral military action against Iran, Ehud Barak gave one of the clearest signs yet that Israel's support for new US and EU sanctions remains strictly limited.

"We are determined to prevent Iran from turning nuclear," he told the World Economic Forum in Davos. "And even the American president and opinion leaders have said that no option should be removed from the table.

"It seems to us to be urgent, because the Iranians are deliberately drifting into what we call an immunity zone where practically no surgical operation could block them."

Although Israeli intelligence and military officials have privately spoken of Iran's nuclear programme entering a "framework of immunity", it is the first time that a senior figure in Benjamin Netanyahu's government has done so in public.

Israel's fears that it might soon be too late to launch military action were bolstered earlier this month when Iran announced that it had begun to enrich uranium at its Fordow plant, which is buried so deep within a mountain it may be impossible for Israeli warplanes or missiles to destroy.

Mr Barak's ministry believes that once the bulk of uranium enrichment is carried out at Fordow, Iran will be in the immunity zone. Israel also reckons that Iran could be in a position to build a bomb within months, although US officials have been quoted as saying that Tehran will not be able to fit a nuclear warhead onto a missile for some years.

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This story probably explains the need of the US to make a bomb that will be a more effective at penetration.  I think without that bomb the Israels will feel compelled to take action before the material is moved into the deeper facility.