The central purpose of deploying strategic nuclear weapons on SSBNs, rather than on other less expensive and technologically demanding platforms, is to assure the survival of these weapons in order for them to conduct a second strike. The rationale is that assured retaliation will dissuade a potential adversary from attempting a preemptive decapitating strike, thus contributing to strategic stability.
Iskander Rehman questions the applicability of this logic in the context of South Asian regional nuclear dynamics and the Second Nuclear Age. From an Indian perspective, with flight times of missiles from estimated launch locations to possible targets being so short — just a few minutes — there is no chance of success for a 'Launch on Warning' policy. Having adopted a 'No First Use' policy, the survivability of India's retaliatory capability is crucial, which means it has little choice but to put a certain number of its missiles on SSBNs.
Nobody has made the case that Cold War policies and scenarios can be cut-and-pasted into the Indo-Pacific scene. But a credible second strike remains a deterrent for states contemplating a preemptive first strike as much in the Second Nuclear Age as during the Cold War, and it is certainly a stabilising factor. As one contributor to this debate has noted, land-based missile silos, launchers and airfields are more vulnerable than SSBNs, and this vulnerability creates instability by tempting a preemptive strike.
As with any policy, there are challenges. Some include command and control, doctrinal and strategic development, engineering, design and quieting, and attaining and maintaining professional excellence and operating standards. But it would be wrong to assume that these challenges cannot be met, and cite them as destabilising factors.
Impact of nuclear cruise missiles on stability
In an earlier submission, I mentioned the potentially negative impact on strategic stability of cruise missiles being deployed at sea. This is for several reasons. One is that the platforms (naval vessels) are dual purpose, in that they are also used for normal fleet operations and are thus equipped with non-nuclear weapons. This creates opacity and uncertainty in cases of encounters at sea between potential adversaries in conditions of heightened tension. Secondly, although technical measures can be built in to prevent unauthorised or accidental launch (as is the case with US Navy Tomahawks), launchers and control systems for the cruise missiles are often stored with the main non-nuclear armament of the platform, and such technical measures are likely to remain unimplemented. And thirdly, if the case of the Nasr tactical nuclear missile launcher of the Pakistan Army is any indication, the command and control of Pakistan's nuclear armed-naval units will be with the commander of the unit. Thus, launch authority can be delegated to a tactical level, lowering the nuclear threshold dangerously.
Pakistan's apparent strategy is to rely on battlefield nuclear weapons such as the Nasr to counter superior Indian ground forces. The maritime domain has been added to this strategy, with the planned deployment of the nuclear-capable Babur missile at sea, ostensibly to counter India's naval strength. This provocative and risk-prone strategy is one which Iskander Rehman has appositely called 'nuclear brinkmanship'.
Range of India's missiles
A few participants have rightly pointed out the short range of the K-15, currently the only sub-launched missile in India's arsenal. Quite obviously, to be an effective deterrent, India's SSBN the INS Arihant and her successors will need to be armed with missiles of at least intermediate ballistic missile range (3,000 - 5,500km). Until a missile with this range becomes operational, India's sea-based deterrent must clearly be considered to be in a developmental stage.
While the deployment of specific weapons does have a significant impact, there are other factors that contribute to nuclear stability. The most important of these is the stability and maturity of the states concerned in the management of this capability. The India-China situation is not one to cause unease in the sub-continent at the present time. It is the India-Pakistan situation that is cause for concern, primarily because of the overriding influence and control of the Pakistani military in that country's political and security affairs. The egregious stratagem adopted by Pakistan, euphemistically termed 'sub-conventional warfare', promotes terrorist attacks periodically across the border under a virtual nuclear umbrella, and keeps the both countries constantly on the brink.
Nuclear stability is a spin-off from political stability and depends on the will of both parties in any dyad to eliminate nuclear risks; this would appear to be the fundamental problem at present.
Photo courtesy of Flickr user My Past.