The Six Day War and the Nuclear Coup that Never Was

June 29, 2017

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On the eve of the June 1967 war in the Middle East, a small group of men in the Israeli elite considered a doomsday scenario. They all supported Israel having an overt nuclear strategy, but the dovish prime minister, Levi Eshkol, had resisted. Now, with war looming, they felt that their hour had come. Behind the scenes, these bureaucrats, scientists and officers prepared the ground for using Israel’s ultimate weapon: the nuclear bomb.

Three weeks ago, The New York Times revealed part of that story which the newspaper described as the “last secret” of the Six Day War. The truth is, evidence of these events has been out in the open for several years now. Yitzchak Yaacov, a top scientist who served as a senior officer in the Israeli army, had published his memoirs detailing the deliberations for the secret operation already in 2011. Based on this book as well as several interviews, Amir Oren, military correspondent for Haaretz, wrote in the same year a long analysis of the decision-making process surrounding this chapter in Israel’s history. And in 2014, Oxford University Press published a monograph by Or Rabinowitz that distilled all these Hebrew-language sources into an English-language text.

To understand what transpired on the eve of the Six Day War, we have to go back to the debates of the late 1950s and early 1960s. Prime Minister David Ben-Gurion and his young disciples at the Ministry of Defense – Chief of Staff Moshe Dayan as well as Chief-Of-Staff and General Director Shimon Peres – argued forcefully for a Jewish bomb. In their view, the Arab-Israeli conflict was insoluble with Israel being “a castle under siege.” An atomic bomb could deter their Arab foes from harassing Israel. Nevertheless, Finance Minister Levi Eshkol was a skeptic. He believed that the money invested in building the nuclear reactor at Dimona should have been spent on social services. Like other security experts, such as Minister of Labor Yigal Allon, Eshkol maintained that the international community would never allow Israel to use the bomb, and therefore Israel must rely on its conventional capabilities. As long as Ben-Gurion was in power, his policies prevailed. However, in June 1963, Ben-Gurion stepped down and Eshkol succeeded him.

Eshkol could not shut down the nuclear project: That would have been a declaration of war against Ben-Gurion who remained active in politics. Eshkol, however, was not enthusiastic about letting Israel’s nuclear project reach its final destination. He refused, for instance, to allow a nuclear test. This effectively left Israel as a nuclear threshold state. And this is how things remained up until May 15, when Egypt sent its troops into the Sinai and a regional crisis, which would end with the Six-Day War, began.

As the crisis unfolded, at REFAEL, Israel’s top-secret technology agency, teams started working around the clock to assemble Israel’s first atomic bomb. Gen. Ezer Weitzman, deputy to the chief of staff, sent an urgent telegram to Washington. In it, he demanded that Col. Yitzchak Yaacov, who was at the time at RAND on a fellowship, return immediately to Israel. Yaacov was the technical expert who could find solutions to the question of where and how to use the bomb. Weitzman, who previously had been commander of the Air Force, was a vocal and early supporter of developing a nuclear option, even advocating its use. For instance, Weitzman insisted that Israel buy Mirage jets from France rather than Vautour bombers because the former had the ability to carry a nuclear bomb. And he brushed aside all those officers that argued the Vautours were much more suitable to the mission of destroying Egyptian airfields.

When Yaacov landed back in Israel, he was ordered to “prepare everything he had” including Israel’s most destructive weapon. Yaacov gained the impression that several generals were worried that Egypt would use chemical weapons against Israeli troops or launch missiles with chemical warheads against Israeli cities. There wasn’t a shred of evidence that the Egyptians were making preparations to do either. In fact, the Israelis sent an agent, Wolfgang Lutz, to spy on the German scientists who helped Egypt launch its missile program. In the mid-1960s, Lutz reported back in the most emphatic way possible that Egypt’s attempt to manufacture missiles was going nowhere. Indeed, Yaacov himself later admitted he did not believe the Egyptian missiles were operational.

Nevertheless, talking about doomsday scenarios seemed to justify using doomsday weapons. A few days after he came back from the United States, Yaacov went to see the Chief of Staff, Yitzchak Rabin. Rabin had just resumed normal duties after suffering a nervous breakdown. Still morose, he asked no questions and signed a form authorizing Yaacov to plan an operation to detonate a nuclear device at the other side of the border. Yaacov went to REFAEL to survey the efforts to create a nuclear device and started brainstorming with the commander of Israel’s best commando unit – Sayeret Matkal. At some point along the way, the operation received a code name: Samson. Yaacov did not know whether the prime minister was aware of any of these activities.

In any case, the small community of bureaucrats and scientists that dealt with Israel’s nuclear project seemed to be on the verge of overcoming Eshkol’s opposition to a nuclear test. As long as Eshkol prevented them from conducting one, they could not be sure that the bomb would work. However, there were signs that the prime minister was still trying to avoid war altogether and by doing so, stop Operation Samson before it started.

On May 26, two Egyptian MiGs, during a reconnaissance flight, passed over Israel’s reactor in Dimona. Weitzman believed that he could use this event to pressure the prime minister to begin the war. Weitzman told Eshkol that the sortie over Dimona was a sign of an impending Egyptian attack on the reactor, perhaps that very day. Israel must strike at Egypt first, Weitzman insisted, if it was to save the reactor from a direct hit. It was a spurious argument. The Israeli reactor was buried deep underground, beneath tons of steel and concrete, and the compound itself was defended by surface-to-air Hawk missiles and planes that were patrolling the sky. Damaging a reactor under these terms was impossible. The Israelis later learned this themselves when they tried to bomb the Egyptian reactor at Inshas during the Six Day War. Israeli pilots had attacked it numerous times: Despite being superb professionals, they could not even scratch it.

The Egyptians were well aware that the Israeli reactor was a heavily protected target. They flew quickly and at high-altitude above Dimona. They could barely see the compound let alone aim to hit it. Motti Hod, the commander of the Air-Force, did not believe the Egyptians had any chance of harming the reactor. But Weitzman gambled that Eshkol would not know any of that. On May 26, he demanded immediate action. However, Eshkol was         unperturbed. He reminded Weitzman that Foreign Minister Abba Eban was still in Washington. Do you want to start a war without coordinating with the Americans, asked Eshkol?

Five days later, the picture completely changed when Washington let it be known that it would turn a blind eye to an Israeli attack on Egypt. Eshkol was under a lot of pressure to appoint Moshe Dayan, the former chief of staff, as minister of defense. Eshkol, a moderate with the look of a non-descript banker, seemed too vacillating to the Israeli public. Dayan, who led Israel to victory in 1956, with his famous eye patch and decisive demeanor, seemed like the right person to oversee the military during a time of great distress. As long as there was a chance to avoid war, Eshkol resisted because he knew that Dayan would demand an immediate authorization to attack. On June 1, it was clear that war had become unavoidable and Eshkol agreed to invite Dayan into the government. Dayan lost no time. The same day he appointed Tzvi Tzur, his confidant, as a special assistant. Part of Tzur’s portfolio was the nuclear complex.

Tzur had been well aware of the efforts to create and use a nuclear device even before assuming office. After receiving the green light from Dayan, Tzur appointed Yaacov and Israel Dostrovsky, director general of Israel’s Atomic Energy Commission, to head a special committee that would oversee Samson. The shape of the coming operation became more and more concrete. Yaacov chose a site in which the device would be detonated – near the large Egyptian compound at Abu Ageila. Yaacov and Dostrovsky even flew there by helicopter and surveyed the area. Before being detected by Egyptian jets, the two were able to spot a canyon where the device could be hidden. According to the emerging plan, two helicopters were to carry the device and land it, while a group of paratroopers would act as diversion against Egyptian units camping nearby.

Amazingly, the Samson operation was never discussed at the cabinet level. It remained hidden from sight, as the ministers discussed and approved only a conventional attack on Egypt. On the morning of June 5, 1967, the first day of the Six Day War, the Israeli Air Force wiped out Egypt’s air force. Yaacov maintains that exactly at that time, all the men involved in Operation Samson were in a state of high readiness. However, as soon as it became known that Egypt was about to face certain defeat, Samson was canceled. All these perpetrations were for naught. Years later, Tzur took great care to distance himself from the whole affair. He claimed that he had been involved merely in examining the feasibility of such an operation, not in actually planning it.

The operation was an extremely dangerous, one might say even reckless, endeavor. It was not for nothing that the operation received a code-name invoking the biblical hero who brought the walls of the temple down, killing himself and his enemies in the process. The site chosen was a few dozen kilometers from the border and it was highly likely that poisonous fallout could be swept by winds into Israel’s territory. Yaacov, however, insisted that on the eve of war everything had been set to go. To his last day, he regretted that Israel did not demonstrate its nuclear capabilities.

This was not the last attempt to use the Arab-Israeli conflict to force the Israeli government to allow a nuclear test. Six years later, during the second day of the Yom-Kippur War, on  October 7, 1973, Dayan tried to convince then Prime Minister Golda Meir to allow the use of nuclear weapons. Dayan made a rather gloomy presentation of the dire situation in the northern front and was exaggerating for effect. After most of the other participants in the meeting had already left, Dayan, nonchalantly, his hand on the door knob as if he was about to leave, suggested that Golda could authorize preparations for the use of the ultimate weapon. Dayan even made sure the director of the Atomic Energy Commission, Shalhevet Frayer, was there. However, two other ministers who attended the meeting, protested loudly and Meir told Dayan “to forget about it.” And indeed, as in 1967, Israel did just fine during the Yom Kippur War without using nuclear weapons. In both cases, proponents of an overt nuclear strategy tried to artificially insert the use of nuclear weapons into the campaign in order to show that they were useful. On both occasions, they inflated the danger that Israel faced in order to bolster their argument. Ironically, Israel’s experience during its two most consequential wars proved the very opposite: Israel could succeed without employing nuclear weapons. The Jewish state’s impressive conventional capabilities were enough to carry it to victory.


Guy Laron is a senior lecturer at the Hebrew University of Jerusalem and author of The Six Day War: The Breaking of the Middle East (Yale University Press, 2017).

Image: National Photo Collection of Israel

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