Jeffrey Lewis is Director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies, Monterey Institute for International Studies, and editor of Arms Control Wonk.
The place to start any discussion about the future of extended deterrence – which is essentially an American phenomenon – is with a heresy: there is no such thing as the 'nuclear umbrella'.
Yes, the US has security commitments. For example, the ANZUS Treaty committed the parties to 'act to meet the common danger' from an armed attack 'in the Pacific Area on any of the Parties'. And, yes, the US also has a very large arsenal of nuclear weapons that is second to none.
But there is no specific commitment to use any of those nuclear weapons in defence of any ally. The ANZUS Treaty and other US defence agreements do not commit the US to use nuclear weapons. The nuclear umbrella is, at best, an inference. It is, in certain cases, a very reasonable inference, of course. And, were I Kim Jong Il, I wouldn't push it.
One way to think about much of the history of extended deterrence is as a kind of conjuring trick or alchemy – an effort to make real this commitment that is merely implied by the dual reality of US security commitments and the existence of nuclear weapons.
In Europe, this trick took the form of planning activities and 'nuclear sharing' arrangements in which European pilots in so-called 'dual capable' aircraft trained to drop American nuclear bombs. In other places, like Japan (until 1972) and South Korea (until 1991), the commitment was implied by US nuclear weapons stationed on their territories. Read More
With the withdrawal of US nuclear weapons from South Korea in 1991, there are no US nuclear weapons forward deployed in the Asia Pacific. Instead, American officials have largely pointed to specific capabilities in the American arsenal that are said to be maintained for the unique task of extend deterrence, on the grounds that if we are willing to spend money, we must be serious.
So, for example, in 2001, the Bush Administration told Japan that the US was retaining the option to deploy nuclear-armed Tomahawk missiles (which were sitting in storage) on US attack submarines just to show we were serious about defending Japan.
The problem with this approach is that US conventional and nuclear capabilities continue to evolve – relying on hardware commits us to those capabilities long past their obsolescence. The US would not, under any conceivable circumstance, have redeployed the nuclear Tomahawk. All along, the Navy intended to retire the system in 2013.
In 2010, the Obama Administration had to choose between explaining to Tokyo that, perhaps, American officials hadn't been entirely truthful in 2002 and the system would be retired, or spending money the Navy didn't have to maintain the system in storage. Fortunately, the Obama Administration decided to proceed with the retirement of the nuclear Tomahawk. The Administration calculated, correctly, that consultations were much more important than the nuclear Tomahawk.
Unfortunately, the 2010 Nuclear Posture Review also continued the short-sighted practice of pointing to one shiny piece of hardware to replace another. This time, the US asserted that its commitment to extended deterrence was demonstrated by the effort to make nuclear-capable the Joint Strike Fighter (and extend the life of the B61 nuclear gravity bomb it would carry) and maintain the capability to forward deploy US bombers, like the B2, particularly in Guam.
These are, however, irrelevant capabilities that may not survive the current budget austerity. There are no military missions for the B61s deployed in Europe – one NATO official admitted to me that 'we would never drop a B61 off the wing of an airplane' – and the Air Force does not want to spend money giving the JSF an obsolete nuclear capability (nor do our European partners seem keen to modernise their own 'dual capable' aircraft).
Nor would the US forward deploy nuclear-armed B2s, either to Guam or elsewhere (conventionally-armed bombers are another matter). The B2 can reach targets from North Korea to Iran directly from Missouri, which is what the US did in the early stages of operations against Yugoslavia, Afghanistan and Iraq.
Either this Administration or the next is going to end up explaining that the 2010 Nuclear Posture Review, in its own way, was not entirely truthful.
Perhaps the solution is to stop talking about extended deterrence as though it were a separate mission. Instead, we should talk about core deterrence – the central mission of nuclear weapons to deter nuclear attacks against the US, our forces abroad and our allies and partners. One advantage to talking about core deterrence is that it forces us to set aside the hardware and focus on the real question: how do we demonstrate that an ally is part of the core?
On the narrow subject of nuclear weapons, this means emphasising consultation and joint planning that binds countries together. But more broadly, changing our language reflects the reality that the credibility of the 'nuclear umbrella' is really just a manifestation of the credibility of our shared interests and values. Forging an alliance on this basis isn't quite as easy as pointing to shiny new piece of hardware, of course, but it is likely to endure long after this bomb or that missile has gone to rust.
The Nuclear Reactions column is supported by the Nuclear Security Project of the Nuclear Threat Initiative, as part of a wider partnership between the NSP and the Lowy Institute.
Photo by Flickr user solidether.