(MT Davila, Matthew Shadle, and Tobias Winright contributed to this post)
In 1837, Britain unleashed “fire and fury” against a wooden steamboat. Crossing the river into US territory, they attacked The Caroline, set it on fire and sent it over Niagara Falls, killing an American citizen in the process. In the subsequent diplomatic spat, the British claimed that the action was self-defence, since the vessel was being used to supply arms to Canadian rebels. US Secretary of State Daniel Webster argued that the attack was unnecessary, disproportionate to the threat and an infringement of US sovereignty. Webster, a noted jurist, gave a clear and subsequently much quoted statement of the criteria for legitimate pre-emptive self-defence: the action must not be “unreasonable or excessive” but rather limited by necessity, which must be “instant, overwhelming […] leaving no choice of means, and no moment of deliberation.”
John Bolton—President Trump’s pick to replace General McMaster as his national security advisor as he prepares for a summit with North Korean leader Kim Jong Un—argues that the principles Webster articulated should no longer apply in the nuclear age. His argument rests on two points: (1) that today’s weapons of mass destruction warrant a broader concept of what constitutes an “imminent threat” than was applicable in “the age of steam” and (2) that the Caroline Test has been flouted to the point that it can no longer be regarded as a binding principle of International Law. Hence, he concludes that “it is perfectly legitimate for the US to respond to the current necessity posed by North Korea’s nuclear weapons by striking first.”
We and a number of Christian theological ethicists have argued that a US first strike on North Korea would not currently be justified as an act of anticipatory self-defence or legitimate pre-emption, since the threat is inchoate and speculative: there is no evidence that an attack is imminent. According to Bolton, we are just plain wrong: the threat is imminent and our case against a preventive attack “rests on a misinterpretation of a standard that derives from pre-nuclear, pre-ballistic-missile times.”
We can all agree that the Caroline criteria were reasonable at the time, and the proposed US first strike on North Korea would not meet that standard. Bolton’s case for a relaxation of the criteria depends on a comparison he makes between the “age of steam” and the world of contemporary military technology. The destruction of the Caroline belonged to an age in which it was still possible to police an outer defence perimeter three nautical miles from a nation’s shores, since cannonballs from enemy ships could not threaten the homeland from further out at sea. By contrast, in our nuclear armed, ballistic-missile age, an attack can be launched much more quickly from much greater distances.
Certainly, the stakes are higher now than they were in Webster’s day. But a more interesting comparison is between the current situation and the prevailing circumstances in the spring of 1945, when the UN Charter framework was negotiated to try to protect future generations from the scourge of war. Although the impending dawn of the nuclear age was still a closely guarded secret, the era in which border walls or policing of territorial waters could provide any serious defence against an aggressive state were long over. Under circumstances in which recent experience had demonstrated irremediable vulnerability to unethical attacks on civilian populations, the international response was to try to build a system to deter aggression whilst reaffirming states’ existing inherent right to self-defence, not to try to make the definition of “imminent attack” more permissive.
Contemporary threats, including weapons of mass destruction in the hands of rogue states, certainly pose new questions which military ethics needs to consider. Michael Walzer has been influential in revitalising just war doctrine as a philosophical and political concept applicable to modern warfare. Under the Caroline Test, physical imminence rather than theoretical threat marks the dividing line between just pre-emption and illegitimate preventive war. Walzer’s formulation is broader, allowing pre-emption in response to a ‘sufficient threat’ that does not meet Webster’s imminence criteria. On Walzer’s view, reasonable pre-emption in an age of WMD requires (1) a manifest intent to injure (2) active preparation that makes the intent a positive danger and (3) a situation where waiting to eliminate the threat magnifies the risk.
The fact that holding back from attacking a rising power allows the threat to increase is the chief source of temptation for states to resort to preventive war. The other two criteria attempt to limit the licence given to those seeking a “self-defence” justification for actions that just war doctrine has traditionally condemned as illegitimate. Walzer is attempting to formulate criteria that would accommodate, for example, Israel’s initiation of the 6 Day War, without opening a loophole big enough for Hitler to drive a Panzer division through. But, whether or not one agrees with Waltzer’s move, it is clear that the current standoff with North Korea would not meet his first two criteria for just pre-emption. Bluster and bellicose rhetoric from the Kim regime do not amount to a manifest intent to injure, and the mere possession of an illegal nuclear weapons programme does not give licence for unilateral action in the absence of clear evidence of both intent and active preparation to mount an attack.
Bolton’s second point is that the Caroline Test is merely customary international law, which needs to be interpreted and modified in the light of changing state practices. This is of course true of all international law, the content of which is underdetermined by the treaties, customs and principles that have been developed to guide the behaviour of sovereign states in an arena that lacks an overarching judicial authority. Anthony Clark Arend has argued that the UN Charter framework has never successfully constrained aggression between nations and declaring it dead would be the most intellectually honest approach. Nevertheless, he strongly advocated that the United States should not adopt this as a policy position, since it risks antagonising allies, emboldening aggressors and undermining American influence around the globe. Furthermore, if Bolton seeks to make this case, the Israeli attack on Iraq’s Osirak nuclear site is an odd choice of example. This attack was unanimously condemned by the international community—strongly suggesting that the Caroline Test was still very much alive in 1981 as a customary principle of international law—the very point Bolton wishes to dispute. Furthermore, it is widely seen in retrospect as having been counterproductive as a means of improving Israeli national security.
We therefore disagree with Bolton’s conclusion that a US first strike would transgress no operative principle of international law, and we regard preventive war threats as a strategic and policy mistake. Even more fundamentally, as Christian theological ethicists, we oppose his conclusion on grounds that it is clearly at variance with long established and widely cherished moral norms. Our position is that recourse to armed force can only be justified as a last resort, and this criterion logically entails all the elements Daniel Webster spells out in the Caroline case. We call on Christian leaders to join us in opposing preventive war against North Korea. In the words of George W. Ball, US Undersecretary of State during the Cuban Missile Crisis, a preventive strike “far from establishing our moral strength […] would in fact alienate a great part of the civilised world by behaving in a manner wholly contrary to our traditions, by pursuing a course of action that would cut directly athwart everything we have stood for during our national history, and condemn us as hypocrites in the opinion of the world.”