The cover-up
When U.S. intelligence discovered the secret facility deep in the desert late in the 1950s, Israeli officials lied to the American Embassy and said it was only a textile plant. When that turned out to be false, Israeli officials offered another explanation: It was purely a metallurgical research installation that did not contain the chemical reprocessing plant needed to produce nuclear weapons.
In December 1960, Ben-Gurion revealed the facility in a speech in the Knesset, saying the 24-megawatt reactor at Dimona would not be completed for four years. It was, he said, “intended exclusively for peaceful purposes.”
Newly elected U.S. President John F. Kennedy, alarmed about the potential spread of nuclear weapons, pressed Israeli officials for regular inspections of Dimona. A 1961 team concluded the site lacked the necessary facilities — such as plutonium reprocessing — needed for a weapons program. Yet U.S. officials wanted regular inspections so they could assure Arab nations, especially Egypt, that Israel did not have a secret bomb program.
The diplomatic record, obtained by the National Security Archive at George Washington University, shows that Israel put off or delayed additional inspections until Kennedy sent a blunt message in July 1963 to a new Israeli prime minister, Levi Eshkol. (Originally the letter was drafted for Ben-Gurion but he resigned before it could be delivered.)
The U.S. commitment to Israel “could be seriously jeopardized if it should be thought we were unable to obtain reliable information on a subject so vital to peace as the question of Israel’s effort in the nuclear field,” Kennedy wrote, adding that U.S. scientists should have unlimited access to all sites at the Dimona complex.
A month later, Eshkol responded, underscoring the plant’s peaceful uses. In 1964, a U.S. inspection team confirmed that there was no weapons-making capability.
But the inspectors were operating under a false assumption — that Israel had no plutonium reprocessing plant. In reality, one was built beneath the reactor. Israelis had built fake walls around the elevators that led to it.
Seymour Hersh’s 1991 book “The Samson Option” detailed the scheme: “A false control room was constructed at Dimona, complete with false control panels and computer-driven measuring devices that seemed to be gauging the thermal output of a twenty-four-megawatt reactor (as Israel claimed Dimona to be) in full operation. There were extensive practice sessions in the fake control room, as Israeli technicians sought to avoid any slips when the Americans arrived. The goal was to convince the inspectors that no chemical reprocessing plant existed or was possible.”