Prime Minister Benjamin Netanyahu says that scenario would be "dwarfed" by the prospect of an Iranian bomb, which he describes as tantamount to a second Holocaust—language that seems to herald a Jewish call to arms.

But the popular, conservative leader has not proven very persuasive. While surveys show a growing minority—now 32-35 percent—of Israelis favor taking Iran on alone, more are opposed. Around a quarter are undecided.

Some commentators ask whether a Jewish state shaped through decades of war has become more fearful of the consequences in the face of Iran, a formidable and distant foe capable, along with Islamist guerrilla allies in Lebanon and Gaza, of raining down thousands of missiles and rockets in retaliation.

Defense Minister Ehud Barak estimates 500 Israelis would die should a strike on Iran, which denies seeking to develop nuclear weaponry, turn into a regional exchange of fire.

Such casualties would be painful for a population of 7.8 million, but would not be on the same scale as Israel's 1 percent death toll from its 1948 independence war and the steep losses from similar conflicts in 1967 and 1973.