military inte=vention seems probable. In particular, a negotiated agreement where Iran i= required to suspend its enrichment activity in Natanz and Fordow might be.acceptable for the regime as long as the construction of the heavy water r=actor in Arak is allowed to continue. An agreement of this kind

r would be quite large. If a military operation would leave the Arak =eactor intact and only focus on the three other critical facilities in Nat=nz, Fordow and Isfahan, Iran could use the reactor for producing material =or a nuclear bomb in the aftermath of the attack. In practice, this means =hat if a

o weapons-grade material -- transfer its existing stock of such fuel to a third country, and shut down one of its two enrichment facilities, known as Fordow. In exchange, the parties will help Iran produce such fuel for medical purposes, which the regime claims is its actual goal. Iran has refused, saying

stment Officer [Note a] Austin Long at Columbia University walked me through the geodynamics of the MOP and how many would be needed to penetrate the Fordow facility. His calculations are a function of soil hardness/density, the weapon's mass and impact velocity, the shape of its cone, and the percentage

anium enrichment to 20 percent purity, which is near bomb-grade; (2) ship abroad the entire stockpile of 20 percent enriched uranium; (3) close the Fordow enrichment facility, which is buried under a mountain near the clerical city of Qom; (4) allow inspectors from the International Atomic Energy Agen

senior U.S. official who is an expert on Iran. The official said some Pentagon war planners believe conventional bombs won't be effective against Fordow and that a tactical nuclear weapon may be the only military option if the goal is to destroy the facility. "Once things go into the mountain, then

, which consists of many facilities, widely dispersed and well protected. The most critical one, nestled deep underground within a mountain, is the Fordow site, and its -three thousand-plus centrifuges have enabled Iran to spin out enriched uranium from uranium hexafluoride gas (UF6) to a level of 19.

would then have to circumvent Iranian air defenses and drop hundreds of precision-guided munitions on the hardened Natanz enrichment facility, the Fordow enrichment site deep in a mountain near Q(n, the Isfahan uranium-conversion facility, the heavy-water production plant and plutonium reactor under

are various ways of making sure that this reactor will remain exclusively peaceful." Asked about a U.S. demand to close the enrichment facility at Fordow, built into a mountainside, Zarif said: "If you sit in Iran, and you see people having concerns about Fordow, the only conclusion you can draw is t

of an Iranian commitment to dismantle its nuclear program. Tehran would stop enrichment at all levels—even for nonmilitary purposes. It would close Fordow, its underground enrichment facility, and the Arak reactor, which is capable of producing plutonium for a bomb. Iran would also have to ship out it

weapons-grade material -- transfer its existing stock of such fuel to a third country, and shut down one of its two enrichment facilities, known as Fordow. In exchange, the parties will help Iran produce such fuel for medical purposes, which the regime claims is its actual goal. Iran has refused, sayi

tiated outcome is far more desirable, and then state that any acceptable negotiated deal must require immediate closing the underground facility at Fordow, freezing of all enrichment above five percent and exporting of all of Iran's stockpile of uranium enriched above that level, and imposing intrusiv

would then have to circumvent Iranian air defenses and drop hundreds of precision-guided munitions on the hardened Natanz enrichment facility, the Fordow enrichment site deep in a mountain near Qom, the Isfahan uranium- conversion facility, the heavy-water production plant and plutonium reactor under

o weapons-grade material -- transfer its existing stock of such fuel to a third country, and shut down one of its two enrichment facilities, known as Fordow. In exchange, the parties will help Iran produce such fuel for medical purposes, which the regime claims is its actual goal. Iran has refused, saying

tiated outcome is far more desirable, and then state that any acceptable negotiated deal must require immediate closing the underground facility at Fordow, freezing of all enrichment above five percent and exporting of all of Iran's stockpile of uranium enriched above that level, and imposing intrusi