- By Stephen M. WaltStephen M. Walt is the Robert and Renée Belfer professor of international relations at Harvard University.
The Obama administration is now rolling out the results of its "Nuclear Posture Review," and presenting it as a significant if not quite revolutionary rethinking of U.S. nuclear strategy. I haven’t seen the full text of the document and have only excerpts and press reports to go by, but the basic idea is to narrow the range of scenarios in which the United States would threaten a nuclear response.
To be a bit more specific, instead of reserving the option of nuclear strikes in response to a nuclear attack, an attack by other forms of WMD (such as biological weapons) or even a large-scale conventional invasion, the review declares that the "fundamental role" of the U.S. arsenal is to deter nuclear attacks on the U.S., its allies, or partners." Accordingly, as a matter of declaratory policy, the Review declares that "the United States will not use or threaten to use nuclear weapons against non-nuclear weapons states that are party to the Nuclear Non-Proliferation Treaty and in compliance with their nuclear non-proliferation obligations."
The exceptions to this narrower focus would be non-nuclear attacks by any nuclear-armed state, or states that the United States deems to be in violation of the NPT. Translation: We still reserve the option of first nuclear use against Iran and North Korea.
Lots of ink will no doubt be spilled analyzing this shift in declaratory policy, and nuclear theologians will spend time at conferences and workshops parsing the fine-grained implications of the change. And stay tuned for assorted hawkish windbags and right-wing think-tankers declaring that this new language has somehow imperiled U.S. security, even though we still have thousands of nuclear weaspons in our arsenal and the strongest conventional forces in the world.
I’ll concede that this new statement may have some public relations value — i.e, it lowers the priority given to nuclear weapons in U.S. strategic thinking, consistent with Obama’s commitment to eventually reduce global nuclear arsenals. But from a purely strategic perspective, this new statement is largely meaningless. To the extent that it does matter, it may even be counter-productive.
Here’s why. No matter what the U.S. government says about its nuclear strategy, no potential adversary can confidently assume that the U.S. would stick to its declared policy in the event of a crisis or war. If you were a world leader thinking about launching a major conventional attack on an important U.S. ally or interest, or contemplating the use of chemical or biological weapons in a situation where the United States was involved, would you conclude that it was safe to do so simply because Barack Obama said back in 2010 that the U.S. wasn’t going to use nuclear weapons in that situation?
Of course you wouldn’t, because there is absolutely nothing to stop the United States from changing its mind. You’d worry that the United States might conclude that the interests at stake were worth issuing a nuclear threat, and maybe even using a nuclear weapon, and that it really didn’t matter what anyone had said in a posture review or an interview with a few journalists. And you’d also have to worry that the situation might escalate in unpredictable or unintended ways — what Thomas Schelling famously termed the "threat that leaves something to chance — and thereby ruin your whole day.
To the extent that nuclear weapons deter — and I happen to think they do — it is the mere fact of their existence and not the specific words we use when we speak about them. In short, nobody can know for certain if, when or how a nuclear state might actually use its arsenal to protect its interests, and that goes for any potential aggressor too. Because the prospect of nuclear use is so awful, no minimally rational aggressor is going to run that risk solely because of some words typed in a posture statement.
Furthermore, the decision to exclude nuclear weapons states, non-signatories of the NPT, or states we deem in violation of it (e.g., Iran) strikes me as both too clever by half and maybe counterproductive. The purpose seems to be to give these states an additional incentive to sign the NPT or to conform to it, but it’s hard to believe that this statement will have that effect on anyone. India, Pakistan and Israel are all non-signatories, but surely they aren’t worried about U.S. "first use" against them and so this statement will be irrelevant to their nuclear calculations.
The real target of this exception is Iran (and conceivably North Korea and Syria). At best, this new statement will have little or no effect, for the reasons noted above (i.e., no one know what we might do in a crisis or war, so pledges of no-first-use are essentially meaningless). At worst, however, excluding Iran in this fashion — which amounts to saying that Iran is still a nuclear target even when it has no weapons its own — merely gives them additional incentives to pursue a nuclear weapons option. In particular, declaring that we reserve the right of "first use" against Iran now (when it has no weapons at all), sounds like a good way to convince them that their own deterrent might be a pretty nice thing to have.
Remarkably, U.S. policymakers never seem to realize that the same arguments they use to justify our own nuclear arsenal apply even more powerfully to states whose security is a lot more precarious than America’s. If the U.S. government believes that "the fundamental role" of U.S. nuclear weapons is to deter nuclear attacks on the United States, and the United States is now proclaiming that it still reserves the option of using nuclear weapons first against non-nuclear Iran (under some admittedly extreme circumstances), then wouldn’t a sensible Iranian leadership conclude that it could use a nuclear arsenal of its own, whose "fundamental role" would be to deter us from doing just that?