How I Learned to Stop Worrying and Love the Bomb
The President-Elect promised on Twitter to "greatly strengthen and expand" America's nuclear capability, generating predictable opprobrium from the usual suspects. The arena of nuclear weapons is especially prone to myths and fallacies. Even the greatest of minds, starting from Noam Chomsky down, have deeply misunderstood the role that nuclear weapons have played since their discovery. In this essay I will try to dispel some of these myths and argue that nuclear weapons are in fact weapons of peace and a force for stability in the modern world.
The first myth is that the number of nuclear warheads is a meaningful metric of nuclear capabilities. So you have this infographic from the grey lady which suggests that US and Russian nuclear capabilities have vastly reduced since the height of the Cold War. Nothing could be further from the truth.
Nuclear warfighting capabilities depend first and foremost on the range and accuracy of delivery platforms (ICBMs, long-range cruise missiles, long-range bombers, field artillery and so on) and intelligence, reconnaissance and surveillance (ISR) capabilities required for detection and targeting of the adversary's nuclear forces. For the principal goal of nuclear warfighting is to disarm the adversary; not attack his population centers. This is because once the adversary is disarmed attacking his cities is unnecessary to obtain political obedience, and destroying all his cities while failing to destroy his nuclear forces guarantees nuclear annihilation.
Imagine the United States circa 2016 with its 7,000 nukes squaring off against the United States circa 1966 with its 32,000 warheads. It would not be a fair fight. US-2016's reconnaissance-strike complex would allow it disarm US-1966 in a splendid first-strike well before the latter could mobilize its bombers and ICBMs. US-2016 would not, of course, consider initiating a first-strike except under the gravest of circumstances. This is because US-2016 could never be absolutely certain of destroying all of US-1966's nuclear forces. In fact, that is the point of US-1966's vast nuclear arsenal. The thirty thousand warheads are not meant to be used but are meant to enhance the survivability of the deterrent against a surprise overwhelming counterforce strike by the adversary.
That also brings us to a much more important question: Is mutual strategic nuclear deterrence stable? The question is more precise than it may seem at first sight. We are not talking about situations where a nuclear-armed state seeks to deter a conventional attack by a non-nuclear weapons state (which would not be mutual). We are not talking about the tactical use of field nuclear weapons in a limited nuclear war (which would not be strategic); nor are we talking about the question of extended deterrence where one seeks to deter the adversary from attacking a protectorate (also not strategic).
There is indeed only one scenario under which mutual strategic nuclear deterrence can be said to fail: An all-out thermonuclear war. In other words, if strategic nuclear deterrence is extraordinarily stable then the existential threat posed by nuclear weapons is minor; if it is not, then advanced human civilization has so far survived the discovery of nuclear weapons by sheer dumb luck. The stability of strategic nuclear deterrence is therefore the most important question of them all.
Strategic nuclear deterrence is extraordinarily stable when both parties have a secure second-strike capability. As long as neither party can expect to destroy the adversary's deterrent by launching a surprise first-strike with near-certainty, the stability of strategic nuclear deterrence is not in doubt. The bar for a second-strike capability is extremely low. There need only be an iota of a doubt that a splendid first-strike will fail to eliminate all of the inferior party's nuclear forces for the superior party to be deterred from ever attempting a first-strike.
Only with highly asymmetric capabilities can one begin to conceive of scenarios where deterrence is not stable. This would happen in a crisis scenario where the weaker party may face a "use it or lose it" situation in the face of the adversary's overwhelming counterforce capabilities. For instance, in an armed confrontation over Taiwan, China may fear that the United States is about to launch a (perhaps purely conventional) disarming first-strike on its command, control and launch capabilities (as the US war strategy called AirSea Battle calls for). Although even in this most extreme of scenarios it is hard see why China would commit suicide for fear of death.
The most interesting implication of these observations is that nuclear arms races, in fact, enhance the stability of strategic nuclear deterrence. Conversely, increasing asymmetry in nuclear warfighting capabilities is destabilizing. The idea that nuclear arms races between great powers increase the risk of thermonuclear war is as wrongheaded as it is pervasive. The increasing asymmetry in the nuclear capabilities between the unipole and the lesser great powers is a more serious cause of concern. Lieber and Press have argued that the United States has sought, and more controversially still, attained nuclear primacy: The US can destroy Russia's entire nuclear arsenal with near-certainty. (Although Russia has since modernized its nuclear forces.)
This brings us to the final delusion concerning nuclear weapons: Global Zero. Even if all nuclear stockpiles could be eliminated in their entirety, that would not remove the existential threat posed by nuclear weapons since states would retain nuclear weapons know-how and the silos would get refilled in the event of a major confrontation. In fact, it would surely undermine strategic nuclear deterrence since great powers would face a strong incentive to be the first to reacquire a nuclear arsenal and in fact threaten its use to blackmail their adversaries into capitulation. Global Zero is an extremely unstable configuration---the most likely path to a nuclear holocaust. It is hard to think of a more counterproductive idea.
I am not saying that the risk of nuclear accidents or inadvertent nuclear use or "broken arrow" or jihadi-general scenarios are not a cause of worry. They are indeed. I'm all for tighter control over nuclear weapons. But these questions of safety and control tend to overshadow the overwhelming benefit of nuclear weapons. By effectively ruling out all-out war between the most powerful states, nuclear weapons have ushered in an unprecedented and open-ended era of great power peace. Only those ignorant of the extraordinary toll of hegemonic war can see nuclear weapons as anything other than an overwhelming force for stability in the modern world.