Edging Toward a Bomb?(Iran may be building nuclear weapons)

The nuclear installation outside Deh-Zire, a village near the city of Natanz, used to be Iran's best-kept secret. Begun in 2001, the plant is little more than a cluster of nondescript sheds on a mountainside 200 miles south of Tehran. One European diplomat says that, from a distance, the facility resembles "a chicken farm surrounded with a lot of fences." According to Western intelligence agencies and Iranian dissidents, however, what's being produced inside is not eggs but enriched uranium.

Iran disputes the implication. While Tehran has admitted that Natanz is being used for uranium enrichment, it insists the material is strictly for civilian power-generating purposes. Yet when officials from the International Atomic Energy Agency (IAEA) visited Natanz last February, what they saw, says one Tehran-based diplomat, "was pretty surprising. We had no idea they were so technically advanced."

One building on the site housed 160 functioning centrifuges--bulky, concrete-mixer-size machines that revolve to separate heavy, relatively unstable uranium isotopes from lighter ones when the element is in gaseous form. IAEA chief Mohamed ElBaradei and other inspectors saw components for 1,000 more centrifuges. That is a lot of potential processing technology for a country that has one nuclear power plant. More troubling, the inspectors observed that some Natanz facilities are being constructed deep underground--safe from the threat of aerial attack. "Much of the installation is being built defensively," says a European diplomat in Tehran. "That obviously gives us cause for concern--that this is not a purely civilian energy program."

Is Natanz the telltale sign that Iran intends to build nuclear bombs? While international experts are suspicious of Iran's intentions, the government's explanation for the plant's existence might be plausible. Centrifuges are dual-use machines, meaning that they can be used to enrich uranium to make nuclear fuel--or to produce the highly enriched uranium (HEU) that's a key component of nuclear bombs. It's not clear just how far the Iranians have gone at Natanz. It takes several months to produce even a small amount of HEU, and the IAEA inspectors found no direct evidence that any had been made. "We're not ...