For readers following closely the issue of possible military strikes (Israeli or U.S.) against Iran’s nuclear facilities, I recommend reading Jeffrey Lewis’s analysis at foreignpolicy.com of the U.S. intelligence assessments. Besides parsing the various National Intelligence Estimates on the Iranian program and dispelling some myths about them, he makes important points about why it is – and will remain – so difficult to determine exactly what the Supreme Leader decides to do with respect to the nuclear program and the steps necessary to weaponize it.
A few years ago I analyzed in this article, titled “The Use of Force Against States that Might Have Weapons of Mass Destruction,” why assessing accurately WMD capabilities is sometimes so difficult – and why some of the impediments to accurately assessing Iraq’s programs were not solved by post-Iraq intelligence reforms or by replacing Bush and Cheney with the Obama administration. This is a real problem for some who think international law requires virtual certainty about an adversary’s capabilities and intentions in justifying anticipatory or preemptive force.
During the 2008 campaign, the Obama team contributed this answer to an American Society of International Law campaign questionnaire: “Sometimes, the preventive use of force may be necessary, but rarely. The experience of Iraq underscores that often, perceived threats are not as real [as] they may seem, and our intelligence may be imperfect. But, when our intelligence is good and defensible we should not rule out the use of force.”
But what constitutes “good and defensible” intelligence? I propose in my article some ways of looking at this question, because in future crises involving the threat or use of force:
we cannot confidently expect moments like during the 1962 Cuban Missile Crisis, when U.S. Ambassador to the United Nations Adlai Stevenson presented “incontrovertible” photographic evidence of Soviet missiles being assembled in Cuban territory to both the U.N. Security Council and a live television audience. Instead, we can expect moments more like Secretary of State Colin Powell’s globally broadcast presentation before the U.N. Security Council forty years later, in which he painted a picture of Iraq’s likely WMD programs with a series of circumstantial pieces of evidence that together indicated likelihood, but far from certainty, of Saddam Hussein’s WMD arsenal.
[UPDATE: In response to a comment, let me add a clarification that I make in my referenced article: I am not suggesting that WMD possession or pursuit alone is sufficient legal cause for self-defensive force. Other necessary elements of a threat sufficient to justify self-defense include the allegedly-hostile party's intent. In future posts I hope to address the intent element (e.g. likely intent to do what? Launch nuclear weapons versus, say, use them as a deterrent umbrella under which to conduct terrorist or other hostile operations?) and how to think about "imminence" of threats (which has both a capability and intent component) in this context. My point here was just to raise some challenging aspects of the capability element that arise in the WMD proliferation context].