Bomb Iran? Not Yet
Iran’s emerging nuclear weapons program poses a grave threat to U.S. national security interests. If left unchecked, Iran may well have a nuclear weapon within the next decade, if not sooner. See this article in the Washington Post. An Iranian nuclear weapon threatens U.S. interests in at least two distinct ways. First, there is a significant risk that Iran might use its nuclear weapons to attack Israel, sparking a nuclear war in the Middle East. Second, there is also a real danger that Iran might supply nuclear weapons or weapons-grade nuclear material to a terrorist group, such as Al Qaeda, which might attack the United States directly. In light of this threat, it may be wise for the United States to launch a preemptive strike to destroy key Iranian nuclear facilities. However, the timing of such a strike is critical, and the appropriate time has not yet arrived.
Before Iran can build a nuclear weapon, it must produce sufficient quantities of weapons-grade nuclear material: either plutonium or highly enriched uranium. At present, the uranium enrichment route appears to be the more immediate threat. Iran has a uranium enrichment facility at Natanz, about 200 miles south of Tehran. See this link. At Natanz, there is a pilot plant that has produced small quantities of enriched uranium. If Iran relied exclusively on the pilot plant, it would take many years to produce enough enriched uranium for a single nuclear weapon. In addition to the pilot plant, though, Iran is building a commercial-scale enrichment plant. See the IAEA report here. Iran is steadily expanding the commercial plant by adding new centrifuge machines. As Iran continues to install new machines, its capacity to produce weapons-grade uranium will increase.
In the near term, IAEA inspectors who are on the ground in Iran will be able to verify that Iran is not using the commercial-scale facility to produce weapons-grade nuclear material. The fear, though, is that Iran will produce low-enriched uranium (which is not useable for nuclear weapons) under the watchful eye of IAEA inspectors while it continues to install new machines. Then, once Iran has gained sufficient experience operating the enrichment plant, and installed a sufficient number of centrifuge machines to acquire large-scale production capacity, it will kick out the IAEA inspectors and begin rapid production of weapons-grade uranium.
In light of the threat that an Iranian nuclear weapons program would pose, the United States must not allow this scenario to unfold. In the near term, it makes sense to pursue negotiated solutions, and to work through the U.N. Security Council to continue application of sanctions. If, however, Iran continues to expand its uranium enrichment capacity, the United States should launch a preemptive strike to destroy both uranium enrichment facilities at Natanz before Iran attains the capacity to produce one bomb’s worth of material per year. The best approach would be to obtain Security Council authorization before launching a preemptive strike. However, if Russia and/or China balk (which seems likely), the U.S. should be prepared to act unilaterally.
In contrast to an attack on a nuclear reactor, or a nuclear fuel reprocessing plant, the radiological harm caused by attacking a uranium enrichment facility would be fairly small. No doubt, the political repercussions of such an attack would be dramatic. Even so, the risk of inaction is sufficiently high that we should be prepared to handle the political fallout from a U.S. attack on Iran to avoid the security risks associated with an Iranian nuclear weapon.
Some of my international law colleagues may contend that a preemptive attack on Iran’s uranium enrichment facility would be a violation of international law. That is true. I will not attempt to justify such an attack by using the rubric of self-defense, because any such justification stretches the concept of self-defense well beyond the breaking point. In any case, there are times when it is necessary to violate international law in order to protect vital national security interests. With respect to the Iranian nuclear threat, we have not yet reached that point – but we are getting close.