The Nuclear Option

Posted on April 8, 2006

If you thought the Administration had completely exhausted their supply of monumentally bad ideas, Seymour Hersh’s latest report in the New Yorker will set you straight.

The first few paragraphs don’t say anything you probably don’t already know. But then, about a third of the way in, it starts getting shocking.

Last month, in a paper given at a conference on Middle East security in Berlin, Colonel Sam Gardiner, a military analyst who taught at the National War College before retiring from the Air Force, in 1987, provided an estimate of what would be needed to destroy Iran’s nuclear program…
One of the military’s initial option plans, as presented to the White House by the Pentagon this winter, calls for the use of a bunker-buster tactical nuclear weapon, such as the B61-11, against underground nuclear sites. One target is Iran’s main centrifuge plant, at Natanz, nearly two hundred miles south of Tehran… The elimination of Natanz would be a major setback for Iran’s nuclear ambitions, but the conventional weapons in the American arsenal could not insure the destruction of facilities under seventy-five feet of earth and rock, especially if they are reinforced with concrete…
The lack of reliable intelligence leaves military planners, given the goal of totally destroying the sites, little choice but to consider the use of tactical nuclear weapons. “Every other option, in the view of the nuclear weaponeers, would leave a gap,” the former senior intelligence official said. “ ‘Decisive’ is the key word of the Air Force’s planning. It’s a tough decision. But we made it in Japan…”
The Pentagon adviser on the war on terror confirmed that some in the Administration were looking seriously at this option, which he linked to a resurgence of interest in tactical nuclear weapons among Pentagon civilians and in policy circles. He called it “a juggernaut that has to be stopped.” He also confirmed that some senior officers and officials were considering resigning over the issue.

(Emphasis mine.)

You read that right — there are actually people arguing for the use of nuclear weapons against Iran.

For reference, here’s some information on the B61-11 air-delivered tactical thermonuclear weapon, also known as the “bunker buster”.

The argument being proffered is that Natanz and other Iranian nuclear production facilities are buried so far underground that only a nuclear weapon can guarantee taking them out. The problem is, it’s not clear that even a tactical nuke can do that. The centrifuge facility at Natanz, for example, is described by GlobalSecurity.org as “hardened with a roof of several meters of reinforced concrete and buried under a layer of earth some 75 feet deep.” Can a B61-11 reach down that far underground? Tests in Alaska’s frozen tundra have not been encouraging:

The frozen soil proof drop tests conducted in Alaska in March 1998 suggests that the earth-penetration capability of the B61-11 is limited. During the test, two B61-11 shapes were dropped from a B-2 bomber at 8,000 feet. The two shapes hit the ground some 45 feet (15 meters) from each other. The Air Force said the B61-11 only proved capable of penetrating some 6-10 feet (2-3 meters) into the frozen soil. At best the weapon would penetrate 15-25 feet (5-8 meters). A photo taken of the retrieval of one of the bombs in Alaska suggests the penetration depth was around 18 feet (6 meters).

Those tests were just of the bomb’s earth-penetration capability, of course; they didn’t include the actual detonation of the nuclear warhead, which presumably would dig up some more of that dirt. But could it reach down the extra fifty or sixty feet it would need to in order to shut down the centrifuge for good?

I don’t know, and I hope to God that we’re not about to find out.

(Much thanks to John Robb for the pointer.)

UPDATE (Apr. 10 2006): ArmsControlWonk.com says that conventional (i.e. non-nuclear) penetration munitions would be more than adequate for taking out a facility like Natanz.