Official says Iran nuke weapons assessment casts doubt on U.S. intelligence
"The American misconception concerning Iran's nuclear weapons is liable to lead to a regional Yom Kippur where Israel will be among the countries that are threatened," Dichter said in a speech in a suburb south of Tel Aviv, according to his spokesman, Mati Gil. "Something went wrong in the American blueprint for analyzing the severity of the Iranian nuclear threat."
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Of course if Israel is truly convinced that Iran is pursuing nuclear weapons and that the US is not going to attack Iran, it would make sense for Israel to carry out a first strike of its own. Any such attack by Israel would surely be less devastating to Iran than a similar US attack, leaving it more options for retaliation.
Iran vows retaliation if Israel attacks
It would surely get very ugly.