This summer’s nuclear showdown between the United States and North Korea, largely manufactured by the bravado and bluster of the President of the United States, seemed to conclude “not with a bang but with a whimper,” until yesterday’s missile test overflying Japan. As a result, the underlying question, how to best prevent a U.S.-North Korean nuclear war, as Pyongyang continues to push for “full spectrum deterrence,” endures.
Among other things, this summer’s crisis highlights the belief held by some U.S. policymakers that an alleged irrational actor such as North Korea cannot be deterred from launching its nuclear missiles by threatening nuclear retaliation. For example, U.S. National Security Advisor H.R. McMaster in an interview this month said that “classical deterrence theory” does not apply to North Korea. At the same time, U.S. officials (including U.S. President Donald Trump) have repeatedly floated the idea of preemptive military strikes against North Korean missile sites as an ostensible last ditch effort to deter Pyongyang.
Given that North Korea has time and again made it clear that it would immediately counter any conventional attack with overwhelming force including nuclear weapons (Vipin Narang has coined this posture “Asymmetric Escalation”), U.S. preemptive military strikes would almost certainly trigger a North Korean nuclear response. North Korea has expanded its nuclear arsenal to up to 30 weapons. Once such a response occurs, the United States might retaliate in kind and launch nuclear missiles. The result would be the end of a powerful moral taboo about the use of nuclear weapons. Indeed, once the spell is broken after the first nuclear bomb has exploded, the likelihood of nuclear war in other parts of the world will have increased markedly.
Underlying the so-called nuclear taboo, a burgeoning international norm against the use of nuclear weapons, is that nuclear deterrence — a function of a country’s nuclear capabilities, doctrine, and command and control procedures for launching nuclear weapons — alone has not prevented nuclear war since 1945, but rather a gradual international consensus that prohibits states from ever using the “Bomb.” This hypothesis is backed up by the work of several scholars. Nina Tannenwald in an influential paper (followed by a book), argues:
A normative prohibition on nuclear use has developed in the global system, which, although not (yet) a fully robust norm, has stigmatized nuclear weapons as unacceptable weapons of mass destruction (…) Ultimately, in delegitimizing nuclear weapons, the nuclear taboo has constrained the practice of self-help in the international system. States are not free to resort to nuclear weapons without incurring moral opprobrium or political costs. National leaders are forced to seek alternative technologies for use in war or defense or else risk being classified as outside the bounds of ‘civilized’ international society.
In her study, Tannenwald acknowledges that given her focus on the United States, her thesis does not hold for all countries. Yet a wargame held in the 1970s in the Soviet Union that involved the Soviet Premier Leonid Brezhnev pushing a button to launch three intercontinental ballistic missiles fitted with dummy warheads indicates that the idea of a nuclear taboo did perhaps go beyond the United States. According to Soviet General Adrian Danilevich, who was present during the exercise:
[W]hen the time came to push the button, Brezhnev was visibly shaken and pale and his hand trembled and he asked Grechko several times for assurances that the action would not have any real world consequences. Brezhnev turned to Grechko and asked, “Are you sure this is just an exercise?
Furthermore, other scholars have supported Tannenwald’s proposition. Jeffrey Lewis states that, “the implication of this norm, of course, is that we can’t actually use nuclear weapons.” According to Lewis, John Hersey’s book Hiroshima was an important early contribution paving the way for the nuclear taboo. “Over time, we’ve come to see nuclear weapons as Hersey saw them, as the ultimate expression of material and spiritual evil of total war,” he writes. Yet, Lewis also cautions: “I am glad we’ve constructed a norm against the use of nuclear weapons, but let’s not kid ourselves. We’ve constructed it. And like any human construction, it can be repurposed.”
The academic Steven Pinker sees the gradual establishment of the nuclear taboo as part of a larger “humanitarian revolution” among the public focused on non-combatant immunity. “The nuclear taboo emerged only gradually…. It began to sink in that the weapons’ destructive capacity was of a different order from anything in history, that they violated any conception of proportionality in the waging of war.” By the 1990s, Pinker reasons, aerial holocausts like Hiroshima, Dresden and North Vietnam were simply no longer politically acceptable to the American public. Yet it remains unclear how rooted this norm against the use of nuclear weapons truly is among people and policymakers.
According to an August 2017 study, when Americans are presented with a trade-off between a U.S. nuclear attack and the death of thousands of American servicemen, a large percentage would approve of nuclear strikes. “Contrary to the nuclear taboo thesis, a majority of Americans are willing to support the use of a nuclear weapon against an Iranian city killing 100,000 civilians,” the study finds. “Contrary to the theory that Americans accept the noncombatant immunity norm, an even larger percentage of the U.S. public was willing to kill 100,000 Iranian civilians with conventional weapons.” Indeed, Americans are willing “to kill two million Iranian civilians to save 20,000 U.S. soldiers.”
Also, despite what the film War Games suggests, there appears to be little hesitation among missile crews to fire intercontinental ballistic missiles in real life, according to Ron Rosenbaum in his book How the End Begins:
It would be nice to believe. But that certainly did not filter down to the missile crewmen I interviewed, who were mainly concerned (…) with making sure they could carry out the genocidal threat of deterrence. Instead, it was almost taboo (…) to talk about reasons for not committing retaliatory genocide, such as questioning the sanity of whoever gave the order.
In addition, it is impossible to ascertain whether the nuclear taboo would influence individual leaders during an international crisis, for example, when the launch of Russian intercontinental missiles has been detected. Furthermore, the causal relationship between the nuclear taboo and nuclear deterrence remains underexplored. For example, what often could be seen as evidence of the nuclear taboo at work could, in some cases, be deterrence or vice versa.
As Jill Lepore states: “Our nuclear-weapons policy rests on a seven-decade-long history of events that have never happened: acts of aggression that were not committed, wars that were not waged, an apocalypse that has not come to pass.” At the end, absent a nuclear war, both nuclear deterrence and the nuclear taboo are nonfalsifiable theoretical concepts that need to be accepted by all sides to “function as instruments of nuclear war avoidance.”
Indeed, repeated arguing that deterrence works is meant to be a self-fulfilling prophecy and to strengthen its effect. One scholar goes as far as to say that deterrence requires scholars to commit “epistemological self-censorship” given that outside the box thinking could be dangerous. As a consequence, “innovations are often about an adjective or prefix: the most recent innovations would be winter-safe, tailored, or cross-domain deterrence (…).” In brief, deterrence only works if we believe that it works: the existence of nuclear weapons alone does not suffice.
Yet, the effectiveness of nuclear deterrence can be undermined by the nuclear taboo since the latter in essence implies that nuclear weapons will never be used — never mind the existence of elaborate nuclear warfighting strategies. Such a disclosure, that an accepted norm against the use of nuclear weapons exists within a country, invariably reduces the credibility of its nuclear deterrent. If pushed to the limits in a showdown, there is consequently an increased risk of nuclear conflict and the impression that one can get away with a nuclear first strike without having to face retaliation. In short, the taboo could undo the taboo.
Conversely, the threat of preventive military strikes against North Korea and the Trump administration’s willingness to accept nuclear war as an outcome undermines both nuclear deterrence and the nuclear taboo simultaneously and independent of their relationship to one another. Implying that current U.S. nuclear posture cannot deter Kim Jong-un and that the nuclear taboo is not credible enough to contain irrational behavior weakens the credibility of both and makes them less effective in preventing nuclear conflict.
In other words, we have to realize that nuclear deterrence and the nuclear taboo are social constructs — a shared assumption about political and military realities — and as such can only contribute to strategic stability (i.e. peace) if there is a consensus that they are real. Trump’s talk of preventive war is gradually undermining this shared assumption influencing the U.S.-North Korea nuclear relationship by denying the effectiveness of the two social constructs underpinning it, and that’s a very dangerous development.
The absence of these two restraining influences will embolden North Korea to maintain its aggressive nuclear posture vis-à-vis the United States and its regional allies increasing the risk of accidental nuclear war. It could also force the United States to adopt more aggressive and unorthodox methods to try to influence North Korean behavior (Ever heard of the “madman theory?”). This could leave the United States not only in the position of a less credible nuclear power in a face off with its chief nuclear competitors, China and Russia, but also raises the prospects of nuclear war across the board.