Emory International Law Review Volume 27 Issue 1 2013 Contextualizing Military Necessity Nobuo Hayashi Follow this and additional works at: https://scholarlycommons.law.emory.edu/eilr Recommended Citation Nobuo Hayashi, Contextualizing Military Necessity, 27 Emory Int'l L. Rev. 189 (2013). Available at: https://scholarlycommons.law.emory.edu/eilr/vol27/iss1/6 This Article is brought to you for free and open access by the Journals at Emory Law Scholarly Commons. It has been accepted for inclusion in Emory International Law Review by an authorized editor of Emory Law Scholarly Commons. For more information, please contact [email protected]. HAYASHI GALLEYSPROOFS2 7/16/2013 10:26 AM CONTEXTUALIZING MILITARY NECESSITY ∗ Nobuo Hayashi ABSTRACT Modern theories correctly reject the Kriegsräson doctrine, according to which the laws of war do not override the necessities of war and it is rather the latter that override the former. One such theory holds that unqualified rules of international humanitarian law (“IHL”) exclude military necessity being invoked de novo as a ground for deviation therefrom, yet not as a ground for additional restraint thereon. This theory—let us call it “counter- Kriegsräson”—is unacceptable for two reasons. First, in none of the three pertinent contexts does military necessity restrict or prohibit militarily unnecessary conduct per se. Seen in a strictly material context of war-fighting, military necessity merely embodies a truism that it is in one’s strategic self- interest to pursue what is materially conducive to success and that it is similarly in one’s strategic self-interest to avoid what is not so conducive. Nor, in the context of IHL norm-creation, does military necessity give the law reason to forbid or limit given conduct. Unnecessary evil does, but unnecessary simpliciter does not, mean illegitimate. In positive international humanitarian law, military necessity functions exclusively as an exceptional clause. If not, or no longer, militarily necessary, deviant conduct simply reverts to being governed by the principal rule. It is the principal rule, rather than the military non-necessity of the conduct or the now inoperative exceptional clause, that renders such conduct unlawful. The second reason for which counter-Kriegsräson is untenable is the same reason for which Kriegsräson is untenable. Positive international humanitarian law has already “accounted for” military necessity. This means that no relevant element of military necessity has survived the process of IHL norm-creation and may consequently be invoked de novo vis-à-vis unqualified rules once this process has validly posited them. Where given conduct is unlawful according to a ∗ Researcher, Peace Research Institute Oslo (PRIO). Formerly, Legal Advisor, Norwegian Centre for Human Rights, Faculty of Law, University of Oslo; Legal Officer, Office of the Prosecutor, International Criminal Tribunal for the Former Yugoslavia. The views expressed in this paper are strictly those of the author. All errors are his and his alone. He wishes to thank Arne Willy Dahl, William J. Fenrick, Guillermo Otálora Lozano, Joanna Nicholson, Simon O’Connor, Greg Reichberg, Henrik Syse, and Inna Uchkunova for their encouragement and thoughtful comments on earlier drafts. HAYASHI GALLEYSPROOFS2 7/16/2013 10:26 AM 190 EMORY INTERNATIONAL LAW REVIEW [Vol. 27 validly posited IHL rule of an unqualified character, then, even if the conduct constitutes material military necessity, invoking it does not “repair” or “right” the conduct’s unlawfulness. Conversely, where given conduct is unqualifiedly lawful according to the applicable rule of positive international humanitarian law, the conduct’s lack of material military necessity does not “wrong” or “vitiate” its otherwise conclusive lawfulness. INTRODUCTION .............................................................................................. 192 I. “MATERIAL” MILITARY NECESSITY: MILITARY NECESSITY IN A STRICTLY MATERIAL CONTEXT ......................................................... 195 A. Military Necessity as a Matter of Amoral, Vocational Competence ................................................................................ 195 1. Purpose, Conduct, and Circumstance .................................. 196 2. Causation Sine Qua Non Not Required ................................ 200 a. No Causation Requirement ............................................ 200 b. No Conditio Sine Qua Non Requirement ....................... 202 3. Material Military Non-Necessities ....................................... 203 a. Wastefulness .................................................................. 205 b. Excessiveness ................................................................. 207 c. Impertinence .................................................................. 208 4. Vocation and Amorality ....................................................... 209 B. Objections ................................................................................... 211 1. Military Virtues vs. Ethical Virtues ...................................... 211 2. Military Virtues as Ethical Virtues ....................................... 217 3. Ethical Virtues as Military Virtues ....................................... 220 II. “NORMATIVE” MILITARY NECESSITY: MILITARY NECESSITY IN THE CONTEXT OF IHL NORM-CREATION ............................................ 223 A. Stipulated Material Military Necessity as an Element in the Legitimacy Modification of Evil Conduct-Kinds but Not of Any Conduct-Kinds ..................................................................... 225 B. Purpose-Kinds Vis-à-Vis Conduct-Kinds ................................... 226 1. The Purpose-Kind Itself Is Illegitimate ................................ 226 2. The Purpose-Kind Itself Is Legitimate .................................. 229 C. Conduct-Kinds Vis-à-Vis Purpose-Kinds ................................... 232 1. The Conduct-Kind Itself Is Considered Evil ......................... 232 a. Evil and Necessary ........................................................ 234 b. Evil and Unnecessary .................................................... 235 c. Preamble of the 1868 St. Petersburg Declaration: Evil Means Illegitimate If Unnecessary ......................... 237 HAYASHI GALLEYSPROOFS2 7/16/2013 10:26 AM 2013] CONTEXTUALIZING MILITARY NECESSITY 191 2. The Conduct-Kind Itself Is Considered Non-Evil ................. 240 a. Non-Evil and Necessary ................................................ 241 b. Non-Evil and Unnecessary ............................................ 241 c. Preamble of the 1868 St. Petersburg Declaration: Does Unnecessary Mean Illegitimate Even If Non- Evil? ............................................................................... 246 D. Special Cases: Conduct-Kinds Considered Evil in an Exclusively Self-Inflicted Way .................................................... 247 1. Minding One’s Own Business .............................................. 249 2. Delegitimizing Self-Inflicted Evil in War .............................. 252 III. “JURIDICAL” MILITARY NECESSITY: MILITARY NECESSITY IN THE CONTEXT OF VALIDLY POSITED IHL RULES ...................................... 254 A. Military Necessity as a Clause Exceptionally Modifying the Content of a Principal Rule ........................................................ 255 B. Specific Requirements of Juridical Military Necessity ............... 255 1. Adopting the Conduct-Instance Primarily for Some Specific Military Purpose-Instance ...................................... 256 2. Conduct-Instance Required for the Materialization of the Military Purpose-Instance .................................................... 257 3. Purpose-Instance, for Which the Conduct-Instance Was Adopted, in Conformity with Positive International Humanitarian Law ............................................................... 259 4. Adopted Conduct-Instance Itself Otherwise in Conformity with Positive International Humanitarian Law ....................................................................................... 259 5. Miscellaneous Observations: Knowledge, Urgency, Scale, and Competence ................................................................... 260 IV. INVOKING MILITARY NECESSITY DE NOVO ........................................ 262 A. Kriegsräson and Its Variations ................................................... 263 1. Material Military Necessity as Conclusive Lawfulness, All Things Considered ................................................................ 264 2. Self-Preservation .................................................................. 265 3. Material Impossibility and Impracticality ............................ 267 B. Counter-Kriegsräson .................................................................. 268 1. Material Military Non-Necessity as Conclusive Unlawfulness, All Things Considered .................................. 269 a. Validly Posited IHL Rules as Necessity-Based Derogations from Peacetime Rules ............................... 271 HAYASHI GALLEYSPROOFS2 7/16/2013 10:26 AM 192 EMORY INTERNATIONAL LAW REVIEW [Vol. 27 b. Purported Survival of Elements of Military Necessity Through the Process of IHL Norm-Creation ................. 272 2. Possibilities of a Validly Posited “Capture Rather Than Kill” Rule? ........................................................................... 278 V. VARIABILITY OF MILITARY NECESSITY ............................................