JERUSALEM: When Egypt and Syria launched a surprise joint offensive in 1973, many Israelis braced for a fight to the finish.

But historians now agree that, for all their rhetoric about destroying the Jewish state, the attacking Arabs — who were eventually repelled — only intended to recapture the Sinai peninsula and Golan Heights, lands lost in a previous war.

One reason posited for the restraint was belief in Cairo and Damascus that Israel could use atomic weapons if fighting spilled over from occupied territory and into home turf.

For Israelis, it served as endorsement for preserving an exclusive, last-ditch nuclear defence. Today, this helps explain Israel’s agitation over the prospect of Iran busting up the monopoly with a nuclear programme of its own.

Privately, Israeli officials acknowledge the immediate risk they see is not in an exchange of nuclear missiles with Iran, but in an increased chance of “classic” regional wars launched in the belief that Tehran has blunted Israel’s strategic edge.

“In 1973, Israel’s nuclear option transformed what could have been an existential war into a contained conflict,” said Israeli military historian Michael Oren.

“A nuclear-armed Iran would risk transforming a contained conflict into a regional and global conflict,” he said.

While Iran denies seeking nuclear weapons, its president, Mahmoud Ahmadinejad, has fuelled war fears by urging Israel’s elimination and questioning whether the Holocaust happened.

Experts note that even if Iran gets the bomb, its primary goal may be to ward off any US-led attack. It would also be many years away from achieving parity with an advanced Israeli arsenal believed to include between 80 and 200 atomic warheads.

But nuclear strategising begins with the binary distinction between countries that do and don’t possess the ultimate weapon of mass destruction. One bomb is enough to join this “club”, and membership confers enormous latitude in non-nuclear conflicts.

“Say that tomorrow Iran gets nuclear weapons, and issues the following ultimatum on Israel: withdraw from the (Palestinian) West Bank or we will fire conventional missiles at you. Do we get into that sort of fight?” said one senior Israeli official with knowledge of nuclear affairs.

“The potential for extortion and major regional instability is mind-boggling,” the official said.

NEIGHBOURHOOD BULLY? While supporting Western diplomatic pressure on Tehran, Israel has made clear it considers pre-emptive strikes — such as its bombing in 1981 of Iraq’s main nuclear reactor — as the last legitimate resort for curbing Iranian atomic ambitions.