By John Thorlin, NSJ Staff Editor –

Writing for the Yale Journal of International Law, Prof. Robert Sloane of the Boston University School of Law delves into the national security variant of the old debate about ends and means–the distinction and relationship between the concepts of jus ad bellum, the law governing resort to force, and jus in bello, the law governing the conduct of hostilities.  Since the introduction of the U.N. Charter, the two concepts have been separated: regardless of how a nation justifies its goals in a given conflict, it must adhere to the same set of in bello rules.  Sloane points out that this belief seems to give rise to obvious contradictions.  If Country X begins a war of conquest, its use of force could simultaneously be unlawful (because Country X had no right to resort to force under the jus ad bellum) and lawful (if Country X’s armed forces follow the rules, the jus in bello).

In his article “The Cost of Conflation: Preserving the Dualism of Jus ad Bellum and Jus in Bello in the Contemporary Law of War,” Sloane examines several historical examples to illustrate the artificiality of modern distinctions between jus in bello and jus ad bellum.  The NATO air campaign against Serbia illustrates the issue in a manner particularly germane to current issues in Afghanistan.  NATO pilots would not fly below 15,000 feet, rendering them virtually invulnerable to anti-aircraft fire and simultaneously increasing the risk to Serbian civilians due to lack of visual confirmation of legitimate military targets.  Sloane argues that NATO’s ad bellum goal of halting the ethnic cleansing of Albanian Kosovars influenced the international community’s appraisal of in bello conduct.

Addressing another current events concern, Sloane points to the debate over whether the nature of terrorism can justify the use of torture.  Ultimately, the very fact that there is a debate over the issue shows that the ad bellum motivation to stop terrorism is muddying the ostensibly clear distinctions of in bello rules regarding treatment of detainees.

Finally, Sloane examines the use of nuclear weapons.  The International Court of Justice ruled in 1996 that jus in bello prohibited the use of nuclear weapons–except when the survival of a state is at risk.  Thus, again, the ad bellum consequences are seen to justify in bello conduct.

Sloane describes the modern rule as a “double proportionality” standard.  The initial use of force has to be proportionate relative to the asserted reason for war (casus belli).  In subsequent retaliatory strikes, the use of force has to minimize civilian harm in a way that would be proportionate to the concrete and direct military advantage anticipated.  Of course, the justification of a concrete and direct military advantage has to refer back to the jus ad bellum, making every action in war revolve around the original casus belli to some extent.

Ultimately, Sloane gives the fairly realist justification that the dualism between jus ad bellum and jus in bello serves the admirable goal of first trying to prevent wars and, given the inevitable failure of the international community to always succeed in that endeavor, restraining both sides so as to minimize the killing.  Allowing exceptions based on ad bellum judgments will lead to a general lack of respect and, subsequently, abandonment of in bello rules.

Sloane’s article is a thought-provoking look at the ends and means debate, but its conclusion seems somewhat forced.  Sloane makes a utilitarian justification for the ad bellum/in bello distinction even though he himself excellently reveals the distinction to be less than logically rigorous.  The realist justification–that the rule can still be useful even if it does not make much sense–seems to be at best an empirical claim lacking in rigorous study.  It would be nice if the dualism prevents belligerent powers from using immoral ad bellum justifications.  However, as advocates of Israel or the NATO action in Afghanistan would quickly point out, the dualism is too blunt an instrument to achieve that end if it prevents countries with legitimate reasons for conflict from taking necessary but costly military actions.

Regardless of whether you agree with Sloane’s conclusion, his piece is a thorough and thoughtful examination of a vitally important issue.