Talk of war was in the air this week, as Israel’s Home-Front Command prepared for a nationwide exercise next Wednesday. Air raid sirens will sound throughout the country, and civil defence organizations will act out what may happen in the event of another Lebanon war.

“Home Front readies for mass evacuations if Hezbollah rockets strike,” read the front-page headline in Thursday’s Haaretz newspaper, referring to the Lebanon-based Shia Islamic movement.

In 2006, people fled from the north of Israel, along the Lebanese border, to safer ground in the centre of the country. The next time, authorities here say, Hezbollah rockets will have the range to strike almost anywhere in Israel.

Talk like this can be self-fulfilling and the worried Lebanese Prime Minister, Saad Hariri, doesn’t like it at all. Four years ago, when Israel went to war against Hezbollah, more than 1,000 Lebanese were killed and substantial damage was done to the country’s infrastructure. Mr. Hariri is hurrying to Washington this weekend to ask Barack Obama’s administration to get Israel to tone down the rhetoric.

Rhetoric or not, it wouldn’t take much to push Israel into action.

Just as it did in 2006, the war could start with a Hezbollah raid across the “Blue Line” to abduct some Israeli soldiers. In such an event, Israel would react quickly and probably as devastatingly as four years ago, with major artillery and rocket attacks on targets in South Lebanon.

This time, however, things could quickly get out of hand.

Benjamin Netanyahu’s government has already announced that if Hezbollah attacks urban centres with the more powerful, long-range rockets the movement is alleged to have, Israel will take the fight to the weapons’ supplier, Syria. In that event, a far more serious conflict could unfold.

With superior air power and hundreds of tanks positioned on the occupied Golan Heights, it would take Israelis only a few hours to move on Damascus, just 40 kilometres away.

At that point, the Syrian leadership and its allies in Tehran would have a calculation to make: In an effort to prevent the capture of Damascus, should Syria launch chemical weapons (probably supplied by Iran) on Israeli targets?

If they did, the leadership would reason, Israel would certainly launch nuclear warheads on Damascus. Realizing that, Syrian and Iranian leaders would think again.

Saddam Hussein faced a similar choice in the 1991 Persian Gulf war. The Iraqi leader elected to fire mostly ineffective, conventionally armed Scud missiles on Tel Aviv, rather than the chemical warheads he had threatened to use. Fear of an Israeli nuclear retaliation almost certainly dissuaded him.

For exactly these kinds of scenarios, Israel has burnished its nuclear image, and will not be easily moved to give it up.

“Israel,” wrote Ariel Levite, former deputy director-general at Israel’s Atomic Energy Commission, in last month’s Washington Quarterly, “remains wedded to its nuclear image as the ultimate existential hedge against serious encroachment of its security interests and an indispensable tool for reassuring its population, allies and partners of its guaranteed viability in the midst of its hostile and turbulent environment.”

Since David Ben-Gurion, Israel’s founding prime minister, charged Shimon Peres with responsibility for developing the country’s nuclear option, Israeli leadership has followed Mr. Peres’s pithy observation about his country’s enemies: “We can’t change their will to attack, only their ability to attack.”

But with a nuclear option, Israel can alter their willingness to attack as well.

That’s why, despite concerted efforts at the current Non-Proliferation Treaty (NPT) conference in New York, and at next month’s meeting of the International Atomic Energy Agency in Vienna, Israel is resisting all attempts to acknowledge the extent to which it has developed nuclear weapons and to join in efforts to make the Middle East a nuclear-weapons-free zone.

It’s not that Israel disagrees with the dream of a nuclear-weapons-free world articulated by U.S. President Barack Obama last year in Prague, which still remains the centrepiece of his foreign policy. Indeed, it was a Jewish prophet, Micah, who uttered the famous prediction that one day “they shall beat their swords into plowshares and their spears into pruning hooks; nations shall not lift a sword against nation, nor shall they learn war any more.”

But while Israeli governments pay lip service to the idea of disarmament, they continue to believe that the risks of moving in that direction far outweigh any immediate benefits.

Take this week’s news that Iran had reached an agreement with Turkey to swap some of Iran’s low-enriched uranium for high-enriched fuel rods. Iran wanted people to think it was finally complying with UN Security Council requirements and that the concerns people had that Tehran’s nuclear program might be developing weapons were unfounded. Israel didn’t buy it; nor did the Security Council’s permanent five, including Russia and China, which have been supportive of Iran in the past.

The precariousness of international sanctions and the ebb and flow of nations’ loyalties just confirm that, when it comes to its existence, Israel cannot trust or count on anyone beside itself.

Israel knows that many countries – maybe even some people in the Obama administration – would like to deal Israel for Iran. If Iran is to be denied nuclear weapons, countries such as Egypt reason, why shouldn’t Israel be similarly denied?

“Success in dealing with Iran will depend to a large extent on how successfully we deal with the establishment of a nuclear-weapons-free zone,” Egypt’s ambassador to UN, Maged Abdel Aziz, told reporters last week at the NPT conference. Egypt has been promoting a nuclear-free Middle East since 1995 and, for the first time, is getting serious support for its initiative. Even Washington seems amenable to a conference of sorts, perhaps as early as next year, to work toward that goal.

But it isn’t going to happen.

Officially, “Israel’s declaratory policy has always embraced nuclear disarmament as a coveted end-state,” wrote Ariel Levite, but only after a “comprehensive political transformation in the attitude of the Arab world and Iran toward Israel.” In other words, Israel will consider disarming when there’s peace on Earth and goodwill among men.

Until then, Israel will follow the teaching of another ancient Jewish hero and remain ready to bring the temple down on itself, as well as its enemies, rather than risk demise alone – the so-called Samson Option.

So, even if Iran says it will disarm and forgo nuclear weapons, “international failure to enforce compliance with nonproliferation obligations does not inspire optimism,” Dr. Levite noted.

“The nuclear issue should be the last to be resolved,” he said, “after the discussion of conventional force issues, as well as those of ballistic missiles and chemical and biological weapons.”

Until then, Israel prefers to keep its deterrent in effect.

Of course, the country’s government hasn’t even acknowledged it possesses nuclear weapons, although that is a common assumption. The most that people in the know will say is that Israel has had a nuclear program since the mid 1950s and that it has the capacity to build and deliver nuclear warheads, but it is not at all certain that it has crossed that threshold.

To that point, Dr. Levite said, Israel has practised “the utmost restraint.”

Israel has signed, although not ratified, the Comprehensive Test Ban Treaty, and says it will not be the first to “introduce” nuclear weapons into the Middle East. It has not signed the Nuclear Non-Proliferation Treaty – so it doesn’t have to tell whether it has nuclear weapons – but says it will adhere to the NPT principles. (India, Pakistan and North Korea also are non-signatories, although they have openly tested and developed nuclear weapons.) This attitude has resulted in Israel not brandishing its nuclear capacity in confrontations with its enemies. “Quite the reverse,” wrote Dr. Levite. “Precisely because it was deemed such a central pillar of Israeli security, it was considered absolutely essential to reserve it solely for the most dire of consequences.”

Israel sees its nuclear image “as the ultimate embodiment of its indigenous capacity to defend itself, by itself, and deter aggressions of all kinds,” wrote Dr. Levite. “Israel has long been skeptical and wary that any external security guarantees would actually safeguard its core security interests, and is fearful of mistakenly relying on such guarantees.”

The idea of a nuclear-free world or even a nuclear-free zone is a lofty goal. But is it the most desirable? Would the world be more stable without nuclear weapons, or with a nuclear arsenal in one’s back pocket?

Israel believes that the fact that no nuclear weapons have been fired since 1945 tells it all. “Nuclear weapons have many profound vices,” notes Dr. Levite, “but deeply ingrained in their very nature has been the virtue to breed exceptional caution in handling or confronting them for fear of bringing about catastrophic consequences.”

It may be that sooner or later Israel will feel compelled to clarify the exact nature of its nuclear capacity – in order to make crystal clear the nature of its deterrence, for example.

But abandoning ambiguity is one thing; abandoning the bomb is quite another.

This modern-day Samson is not likely to let his locks be shorn.