Key Point: Although Israel doesn’t officially acknowledge it, it is well understood that the country possesses a nuclear weapon arsenal (although the exact number of warheads are in dispute). It is similarly well understood that the United States opposed Israel’s nuclear weapons program during the John F. Kennedy and, to a lesser extent, Lyndon B. Johnson administrations. One part of the history that is less well known is that much of the funding for Israel’s nuclear weapons program came from private Americans in an effort that was spearheaded by, Abraham Feinberg, a prominent American who served as an unofficial advisor to both President Kennedy and President Johnson.

Israel’s interest in nuclear weapons basically dates back to the founding of the Jewish state in 1948. The country’s founding leader, David Ben-Gurion, was haunted both by the Holocaust and the unremitting hostility Israel faced from its much larger Arab neighbors. Ben-Gurion viewed nuclear weapons as a last resort option for ensuring the survival of the Jewish state in case its enemies ever used their much larger populations and economies to build conventionally superior militaries.The problem Ben-Gurion and his closest advisors faced was that their young, poor, and relatively unsophisticated country didn’t possess the necessary technological and material resources to support an indigenous nuclear weapons program. Israel’s best hope of acquiring nuclear weapons came from finding a foreign patron. Fortunately for Israel, contemporary circumstances created conditions for it to obtain this support.

Specifically, during the mid-1950s France’s control over Algeria—which it considered part of France and not just another colony—was increasingly contested by a domestic insurgency that was receiving substantial support from the Egyptian leader Gamal Abdel Nasser. Paris responded by eliciting Israel’s help in providing intelligence on the Algerian situation in return for French conventional weaponry. The opportunity to transform this into nuclear cooperation presented itself in 1956 when Paris asked Israel to provide France and Britain with a pretext to intervene militarily in what became the Suez Canal crisis.

Ben-Gurion had major reservations about involving Israel in the scheme. These were overcome when France agreed to provide Israel with a small research reactor similar to the EL-3 reactor France had built at Saclay. Of course, the Suez invasion quickly went awry with both the United States and Soviet Union threatening Israel, France and Britain in different ways to get them to withdraw. France was unable to protect Israel from the superpowers’ threats. Before agreeing to withdraw, however, Israel demanded that Paris sweeten the nuclear cooperation. France agreed to provide Israel with a much larger plutonium-producing reactor at Dimona, natural uranium to fuel the reactor, and a reprocessing plant—basically everything Israel would need to use the plant to produce plutonium for a bomb except for heavy water.

This was a major coup—no country before or since has provided another state with such an extensive amount of the technology required to build a nuclear bomb. Still, it was only half the battle. Ben-Gurion still had to come up with the funds necessary to pay for the nuclear deal for France. How much the Dimona nuclear facilities cost to build is not known, but Israel likely paid France at least $80 million to $100 million in 1960 dollars. That was a massive amount of money for Israel at the time. Furthermore, Ben-Gurion worried that if he diverted defense funds for the nuclear project he invite opposition from the military, which was struggling to field a conventional army that could defeat Israel’s Arab enemies.

Instead, the Israeli prime minister decided to create a private fund to finance the deal with France. As documented by Michael Karpin in his excellent history of the Israel’s nuclear program, The Bomb in the Basement, Ben-Gurion directed his staff simply to “call Abe,” referring to Abe Feinberg. Feinberg was a prominent New York businessman, philanthropist and Jewish American leader with close ties to the Democratic Party. Before America’s entry into World War II, Feinberg had raised money to help European Jews emigrate to Palestine. After the war ended, he—like Ben-Gurion—went to Europe to view the Holocaust concentration camps. He also helped smuggle Holocaust survivors into Palestine at a time when the British had created blockades to prevent illegal Jewish immigration. During this time, he forged lasting bonds with many of the men who would later become senior leaders of the state of Israel. Upon returning back to the United States, he helped lobby President Harry Truman to recognize the Jewish state once it declared its independence. In return, Feinberg helped raise money for Truman’s reelection campaign.

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Thus, it was natural that in October 1958 Ben-Gurion would turn to Feinberg to help raise the funds necessary for the Dimona deal. In fact, this wasn’t the first time Ben-Gurion would turn to American Jewish leaders to raise money for Israel’s causes. Foreseeing there would soon be a war of independence, Ben-Gurion went to New York in 1945 to raise funds to purchase armaments for the Jews in Palestine. This mission was a success. According to Karpin: “In the secret papers of the state-in-the-making the seventeen American millionaires were given the code name ‘the Sonneborn Institute,’ after their host. In the coming years, its members would contribute millions of dollars to buy munitions, machinery, hospital equipment and medicines, and ships to carry refugees” to Palestine.

Feinberg was one of the seventeen millionaires that comprised the Sonneborn Institute. In 1958, Feinberg turned to many of the same members of the Sonneborn Institute, as well as many other Jewish leaders in North America and Europe, in order to raise the money for the Dimona nuclear project after Ben-Gurion’s appeal in 1958. He was widely successful: again, according to Karpin, “The secret fund-raising campaign began at the end of 1958, and continued for two years. Some twenty-five millionaires contributed a total of about $40 million dollars.”

How important was Feinberg’s mission to the success of the Israeli nuclear project? According to Karpin:

If Ben-Gurion had not been sure that Feinberg could raise the millions needed for the project from world Jewry, it is doubtful that he would have undertaken the deal with France. Israel of the 1950s and ’60s could never have paid for the advanced technology, erected the Dimona reactor, and built a nuclear deterrent out of its own resources.

This was not the end of Feinberg’s involvement in U.S.-Israeli relations, however. In fact, after the Democrats retook the White House in the 1960 election, Feinberg became an unofficial advisor to both JFK and LBJ. For instance, in 1961 Feinberg led the effort to persuade Ben-Gurion to allow American inspections of the Dimona reactor.

Zachary Keck (@ZacharyKeck) is a former managing editor of The National Interest.