Chief of Staff Lt. Gen. Benny Gantz told Haaretz Iran "is going step by step to the place where it will be able to decide whether to manufacture a nuclear bomb. It hasn't yet decided whether to go the extra mile."
But Gantz said as long as Iran's facilities are not bomb-proof, "the program is too vulnerable, in Iran's view. If the supreme religious leader Ayatollah Ali Khamenei wants, he will advance it to the acquisition of a nuclear bomb, but the decision must first be taken."
That would happen, Gantz said, "if Khamenei judges that he is invulnerable to a response. I believe he would be making an enormous mistake, and I don't think he will want to go the extra mile. I think the Iranian leadership is composed of very rational people."
Gantz said international pressure on Iran through diplomatic and economic sanctions have begun to pay off.
But he said an Israeli military strike could not be ruled out.
"The military option is the last chronologically but the first in terms of its credibility," Gantz said. "If it's not credible it has no meaning. We are preparing for it in a credible manner. That's my job, as a military man."
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U.S., allies launch airstrikes against Syria