Israeli officials are orchestrating a campaign to have Congress scuttle the Iran nuclear deal by voting it down and overriding a promised presidential veto. Republican presidential hopefuls have jumped on the bandwagon, denouncing the deal as if it heralded the end of the world.

There are indeed very serious concerns about the details, which the administration must try to allay. And Israel, whose right to exist is challenged by Iran, has every right to be concerned.

But before Capitol Hill sinks into hysteria, legislators need to know that many former Israeli intelligence and national security officials oppose their government’s approach -- and think a congressional veto would be a disaster. “This is the best option we have, even if it is risky, even if it is a bad deal,” says Ami Ayalon, a former head of the Shin Bet, Israel’s domestic intelligence service.

Ayalon contends that an imperfect deal is better than the alternatives. “We have to choose between bad options,” he told me during a phone interview from Israel. “We are not living in a perfect Middle East.”

He is correct.

Although Israeli Prime Minister Benjamin Netanyahu contends that Iran‘s program should be completely dismantled, this was never an option. Iran has had the technological know-how to build a bomb for years and, at this point, was clearly unwilling to halt its suspect nuclear energy program.

The kind of limits on that program that might have been possible a decade ago are impossible now.

Before the Iran talks began, the ayatollahs were edging up to bomb-making capacity. “There is no debating that Iran was two to three months from having enough (fissile) material to make a bomb,” Ayalon points out. “The deal pushes Iran back for the next 10 to 15 years from when they will have that material.”

Will the deal work? “Ask me in 10 to 15 years,” he suggests ruefully, but adds, “We should give it a chance. What were our options?”

There were only three choices: a military strike, more sanctions, or a deal.

If Israel attacked Iran’s nuclear sites, Ayalon points out, “We could destroy some of Iran‘s infrastructure and installations and set the program back two to three years, not 10 to 15. If America would attack, with its greater capacity, it could set them back four to five years. “If -- and this is a big if -- the agreement will achieve what we want, we get 10 to 15 years,” he says.

The same point was made in slightly different terms by the former director of the Mossad, Israel’s overseas intelligence agency, Efraim Halevy, who wrote in a recent column: “In the Middle East, a decade is eternity.”

Of course, some in Congress argue that additional sanctions would have forced the ayatollahs to bend. I‘ve yet to talk to an Iran expert, including Ayalon, who believes this.

The ex-Shin Bet chief does believe that Netanyahu’s tough Iran policy -- which he formerly supported -- was key in convincing the international community to impose tough sanctions on Tehran, and that those sanctions brought Iran to the table. But once negotiations began, he says, Netanyahu should have “changed positions. Instead of attacking the negotiations, we should have tried to be as close as possible to the coalition” so as to share intelligence, provide information on Iranian violations, and game out what to do in case Iran cheats.

If Congress votes down the deal and overrides a veto, he believes Israel will be the loser. This is true even though the deal has serious flaws. “This would be the worst scenario,” Ayalon contends, because he doesn‘t believe China, Russia or even Europe would be willing to go back to the status quo ante.

The entire deal would collapse, negotiations would end, and the international sanctions regime would crumble. Iran would be free to restart its production of fissile material (which was halted under an interim accord) and build advanced centrifuges. “We would be creating a chaotic scenario,” says Ayalon, “instead of discussing what would happen if Iran violates the deal.”

Far better, says the former intel chief, for Israel to work closely with Washington to try to make the deal work and offset its flaws, notably the convoluted process of verifying Tehran’s compliance.

Other Israeli security experts tell me this would require the closest U.S.-Israeli intelligence cooperation and a firm U.S. commitment to respond to evidence of Iranian cheating -- even if this puts Washington at odds with its European allies. It would also require the administration to spell out how (or if) it intends to counter Iranian troublemaking in Syria, Lebanon, Iraq and Yemen.

Ayalon‘s bottom line: It makes more sense for Israel to work to strengthen the implementation of this deal than to try to destroy the best of its bad options.

Ex-Mossad chief Halevy agrees. “A moment before we storm Capitol Hill,” he wrote, “led by the Israeli ambassador to Washington, it’s important to hold a profound debate in Israel on whether no agreement is preferable to an agreement which includes components that are crucial for Israel‘s security.”

Israel’s backers in Congress should take these words to heart.

By Trudy Rubin

Trudy Rubin is a columnist and editorial-board member for the Philadelphia Inquirer. -- Ed.

(The Philadelphia Inquirer/Tribune Content Agency)