Hmm, it’s August, things are quiet, time for another wave of hysteria over an imminent Israeli attack on Iran. We’ve seen this movie for a decade — Israel’s “red line” on the Iranian nuclear program has proved of spandex-like elasticity.

(I sometimes imagine the size of the explosion if all the words devoted to the Iranian nuclear program since 2000 were placed in a large container and detonated.)

Israeli newspapers are full of reports that home-front preparedness is inadequate. Only 53 percent of Israelis, they say, have gas masks. Prime Minister Benjamin Netanyahu has just appointed Avi Dichter, a former head of Shin Bet — the Israeli equivalent of the Federal Bureau of Investigation — as the new home-front minister to address these concerns.

Dichter, by the way, has joined a host of former security and intelligence chiefs in saying that for Israel to lead an offensive against Iran would be a “total mistake.”

Wise words; but they have done nothing to dampen the attack-looming chatter of these summer doldrums, with the U.S. election less than 100 days away. One theory in Jerusalem is that the run-up to Nov. 6 is a good moment to attack because President Obama, despite his misgivings, would have no choice but to get behind the Jewish state or lose votes.

Netanyahu is doing nothing to dispel the rumors. Why should he? They provide leverage for tougher Iran sanctions and have no downside for Israel other than creating an impression that, on Iran, it has cried wolf.

Consider this recent post on the International Herald Tribune’s Latitude blog from Shmuel Rosner, the political editor of the Jewish Journal: “I got home Monday evening to find in my mailbox an official reminder: Did we have enough gas masks for the whole family?”

Rosner continues: “These days, Israeli media outlets are competing with one another to run scare stories: Are there enough shelters in Jerusalem for all residents? Does the new text-message missile alert system work properly?”

The Netanyahu government is happy enough with this state of fear: It seeks uncertainty. It takes a rightly skeptical view of the talks on Iran’s nuclear program between Iran and the United States, Russia, China, Britain, France and Germany. These have gone over familiar ground — Iranian offers to stop enrichment to 20 percent and eliminate its stockpile of such uranium against a lifting of sanctions and recognition of its right to enrich to a much lower level — without moving the ball.

Let’s get real: A deal in a U.S. election year is out of the question. Obama will not do it. He is not going to hand the Republicans ammunition on a plate.

Moreover, the Iran led by the Brezhnevian Ayatollah Khamenei is incapable of clear decision-making. It is a nation in the image of its noisy president, Mahmoud Ahmadinejad (remember him?): a lot of bluster over not much. It is given to what James Buchan has called “lachrymose intransigence.” Khamenei is a septuagenarian supposedly standing in for the Prophet. The average age of his wired population is 27. Try getting that system to function.

As Karim Sadjadpour of the Carnegie Endowment for International Peace told me, a deal is unthinkable because “the possibility of ever aligning Israeli psychology, Iranian ideology and the American political calendar is infinitely remote.”

So what should Israel do? Israeli security is incompatible with an Iran armed with a nuclear weapon that says it is bent on the destruction of the Jewish state: That, given history and psychology, is the reality of the situation.

But a unilateral Israeli attack on Iran today would be disastrous. It unites Iran in fury; locks in the Islamic Republic for a generation; gives a substantial boost to the wobbling Assad regime in Syria; radicalizes the Arab world at a moment of delicate transition; ignites Hezbollah on the Lebanese border; boosts Hamas; endangers U.S. troops in the region; sparks terrorism; propels oil skyward; rocks a vulnerable global economy; triggers a possible regional war; offers a lifeline to Iran just as sanctions are biting; adds a never-to-be-forgotten Persian vendetta to the Arab vendetta against Israel; and may at best set back Iran’s nuclear ambitions a couple of years or at worst accelerate its program by prompting it to rush for a bomb and throw out International Atomic Energy Agency inspectors.

Such damage may not amount to an existential threat to Israel — the phrase is overused. It would be a devastating strategic error.

Don’t do it, Bibi.

I do not say this lightly. All the talk of gas masks reflects real Israeli fears, even if they are artfully stoked. Israel must keep in mind that no U.S. president can accept the current Iranian regime going nuclear: Obama has been explicit about this.

Iran is not enriching uranium, as it claims, for a power plant of epic dysfunction. But nor has it yet united the various elements needed to make a bomb. If it ever makes the decision to do so, I expect the U.S. military response to be swift and devastating. The wise choice for Israel is therefore patience.