This week, the world's major powers resumed negotiations with Iran over its nuclear program. Should they fail, the specter of a possible Israeli strike looms large, seeming to grow more likely as Tehran's nuclear program advances. 

In recent weeks, however, the conventional wisdom has shifted to favor the view that Israel is not on the cusp of a strike against Iran. This has been driven in part by public comments from former Israeli security officials -- notably former Mossad head Meir Dagan and former Shin Bet head Yuval Diskin -- questioning the wisdom of such an attack. An Israeli strike is not feasible, the thinking goes, so long as its security community remains divided -- and the thinly veiled threats of Israeli Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak are therefore mere bluster. 

Don't be so sure. Dagan and Diskin's views aren't likely to tell us much about the likelihood of a strike on Iran one way or the other. For starters, they're former officials -- given the sensitivity of this issue, and the recent media misinterpretation of Israel Defense Forces (IDF) Chief of Staff Benny Gantz's remarks earlier this month, no other current members of the security establishment are likely to go public with their views. This means the perspective of those in the room when Israeli leaders decide whether to attack will only be known to the Israeli public after the fact, if at all.

What's more, don't expect the views of Israel's security establishment to determine whether Israel does or does not attack Iran. Just as in the United States, military decisions are ultimately made by the country's elected leaders. And a close look at recent history shows that Israel's politicians have often shown little compunction about overruling the top brass.

In early 1978, Israeli Prime Minister Menachem Begin convened several senior ministers and security officials to brief them on Iraq's rapidly advancing nuclear weapons program. At the time, this group was divided over using force to halt Iraq's nuclear drive: Deputy Prime Minister (and former IDF chief of staff) Yigael Yadin, Defense Minister (and IDF deputy chief of staff during the 1967 war) Ezer Weizman, Mossad chief Yitzhak Hofi, and Military Intelligence chief Shlomo Gazit all opposed a strike. Yet two years later, on October 28, 1980, a vote in the full Israeli cabinet authorized a strike on Iraq's main nuclear reactor -- dubbed Osirak. Israeli F-16s carried out the strike on June 7, 1981, successfully destroying the reactor.

Many of the arguments of those who opposed Begin are today being echoed by former Israeli security officials like Dagan and Diskin vis-à-vis Iran -- and may prove equally unconvincing to Israel's political leadership, regardless of the differences between the two situations. At the time, opponents maintained that there was still time to resolve Iraq's nuclear threat by other means. Moreover, they feared that a strike would not foil Saddam Hussein's efforts to acquire nuclear arms, would justify Iraq's withdrawal from the nuclear non-proliferation treaty, and would unite the Arab and Muslim world around the reconstitution of its program. An attack would draw U.S. and international condemnation, they argued, and could even invite Iraqi retaliation against Israel's own nuclear reactor at Dimona. 

When Weizman resigned in May 1980 (over a different issue), Begin assumed his portfolio, becoming both prime minister and defense minister. This only increased Begin's control over Israeli decision-making. As Weizman himself later recalled, "Begin could talk the cabinet into any decision he wanted ... and he wanted to bomb [the reactor]."

Having lost much of his family in the Holocaust, Begin was undoubtedly driven by the fear that Saddam's acquisition of a nuclear weapon would put Israel in peril of a second Holocaust. "Indeed, this final argument tipped the scales for Menachem Begin," Moshe Nissim, a cabinet minister at the time, later recalled. "[T]he memory of the Holocaust ... remained before his eyes throughout all the discussions." 

Netanyahu views the prospect of a nuclear-armed Iran through a similar prism. "Those who dismiss Iran's threats as exaggerated or as mere idle posturing have learned nothing from the Holocaust," the Israeli prime minister declared at a Holocaust Day commemoration event on April 18. "The memory of the Holocaust obligates us to apply the lessons of the past to ensure the basis of our future. We will never bury our heads in the sand."

But even after Weizman's resignation, several formidable figures still opposed a strike, including Yadin, Hofi, and the newly appointed chief of Military Intelligence Gen. Yehoshua Saguy. Begin delayed the strike for close to eight months in no small measure to buy time to convince Yadin, who had threatened to leave the cabinet over the decision. Begin ultimately prevailed by forwarding to Yadin a plethora of intelligence reports, according to then Chief of Staff Lt. Gen. Rafael Eitan.

Hofi and Saguy, two of Israel's top security officials, never came around to support a strike. But once the order was given, they fulfilled their soldierly duty and carried out what was, at the end of the day, a political decision.

This was by no means the last example of Israeli political leaders overruling key security officials. Israeli Prime Minister Yitzhak Rabin kept IDF officials entirely in the dark throughout the secret negotiations that led to the Oslo Accords in 1993, anticipating stiff opposition from the military establishment. He was right: Shortly after the agreement was inked, then IDF Chief of Staff Ehud Barak strongly criticized the deal, calling it "as full of holes as Swiss cheese." However, he deferred to the right of the political echelon to sign the agreement.

Not long thereafter, Barak opposed the structure of peace talks with the Palestinians as too incremental. By postponing core issues to future negotiating rounds, Barak argued, Israel would fall victim to "salami tactics," prematurely trading away its negotiating assets before the final round. Yet Barak -- and his penchant for gastronomical metaphors -- was overruled again.

Soon, however, the shoe was on the other foot. As prime minister in 2000, Ehud Barak authorized the Israeli unilateral withdrawal from Lebanon despite widespread opposition among the IDF top brass, including then Chief of Staff Shaul Mofaz. 

Right-wing Israeli premiers have shown themselves equally willing to overrule the security establishment. In 2005, IDF Chief of Staff General Moshe Yaalon so staunchly opposed Israel's unilateral disengagement from Gaza that his term was not extended by then Prime Minister Ariel Sharon and Defense Minister Mofaz.

Ironically, the Israeli prime ministers who felt most comfortable facing down generals in political decision-making were former generals themselves. Former General Rabin overruled General Barak over the shape of Oslo. Former General Barak overruled General Mofaz over the Lebanon withdrawal, and former General Sharon overruled General Yaalon over the Gaza pullout. Although Netanyahu himself is not a former general, his close alliance with Barak is reason enough to believe that he will not shirk tradition.

Ultimately, Israel's decision on whether to strike Iran will be the product of myriad calculations, including Israeli perceptions of whether the international negotiations over Iran's nuclear program have failed. No decision has yet been made, according to Netanyahu. He would prefer a peaceful solution, or, if that fails, a U.S.-led operation -- but believes he must be prepared if he does not get his first or second choice. Yet, one fact is certain: The views of former security officials will not be decisive.