In 1967, under the "Atoms for Peace" program launched by President Eisenhower, the US sold the Shah of Iran's government a 5-megawatt, light-water type research reactor. This small dome-shaped structure, located in the Tehran suburbs, was the foundation of Iran's nuclear program. It remains at the center of the controversy over Iranian intentions, even today.
That is because Iran says it needs more fuel for the reactor, which it insists it uses for basic research, and to produce medical isotopes. And the Tehran Research Reactor runs on uranium that is some 20 percent U-235 – an enrichment level higher than that currently produced by Iran's Natanz enrichment facility.
Now Iran has agreed in principle to send most of its current stockpile of low-enriched uranium abroad, so that some other country – most likely Russia – can produce this more-highly enriched fuel for them. In any case, that is what US and European officials say occurred at this week's meeting between Iran and six western powers.
Such a move would consume some two-thirds of Iran's existing stockpile of 3,200 pounds of low-enriched uranium.
The Shah of Iran was a US ally. But even so, the US had qualms about providing him with nuclear technology. The worries were very like those of today: officials thought it possible that Iran would build on nuclear power programs to develop nuclear weapons technology.
A 1974 Defense Department memorandum, recently declassified and posted on-line by the National Security Archive, noted that stability in Iran depended heavily on the Shah's personality. Should he fall, "domestic dissidents or foreign terrorists might easily be able to seize any special nuclear materials stored in Iran for use in bombs".
Iran planned to obtain up to 20 large nuclear reactors in the next several decades, the memo noted. These might produce large quantities of material that could be converted for bomb use.
"An aggressive successor to the Shah might consider nuclear weapons the final item needed to establish Iran's complete military dominance of the region," noted the memo.
In 1978, President Carter and the Shah struck a deal that would have sent eight US-made light-water reactors to Iran, pending Congressional approval. A year later, the Iranian revolution forced the Shah from power and the deal fell apart.
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