U.S. officials say they have no imminent plan to bombard the site, and they have cautioned that an American attack — or one by its closest Middle Eastern ally, Israel — risks devastating consequences such as soaring oil prices, Iranian retaliation and dramatically heightened tension in a fragile region.
Yet as a matter of physics, Fordow is far more vulnerable than generally portrayed, said current and former military and intelligence analysts. Massive new “bunker buster” munitions recently added to the U.S. arsenal would not necessarily have to penetrate the deepest bunkers to cause irreparable damage to infrastructure as well as highly sensitive nuclear equipment, probably setting back Iran’s program by years, officials said.
The weapons’ capabilities are likely to be a factor in discussions with a stream of Israeli leaders arriving in Washington over the next week. The Obama administration will seek to assure the visitors, including Defense Minister Ehud Barak and Prime Minister Benjamin Netanyahu, of U.S. resolve to stop Iran if it decides to build a nuclear bomb.
Israel has signaled in recent weeks that it may launch a preemptive strike against Iranian nuclear facilities, with little or no warning to its U.S. allies. The White House has urged Israel not to move hastily; making clear that the United States has the capacity to disrupt the Iranian program may give the Israelis reason to pause.
‘How many turns do you get?’
In arguing their case, U.S. officials acknowledged some uncertainty over whether even the Pentagon’s newest bunker-buster weapon — called the Massive Ordnance Penetrator — could pierce in a single blow the subterranean chambers where Iran is making enriched uranium. But they said a sustained U.S. attack over multiple days would probably render the plant unusable by collapsing tunnels and irreparably damaging both its highly sensitive centrifuge equipment and the miles of pipes, tubes and wires required to operate it.
“Hardened facilities require multiple sorties,” said a former senior intelligence official who has studied the formerly secret Fordow site and who agreed to discuss sensitive details of U.S. strike capabilities on the condition of anonymity. “The question is, how many turns do you get at the apple?”
U.S. confidence has been reinforced by training exercises in which bombers assaulted similar targets in deeply buried bunkers and mountain tunnels, the officials and experts said.
U.S. officials have raised the necessity of multiple strikes as they warn Israel against a unilateral attack on Iran’s nuclear installations, the officials said. While Israel is capable of launching its own bunker-buster bombs against Fordow, it lacks the United States’ more advanced munitions and the ability to wage a bombing campaign over days and weeks, American officials and analysts said.