The post-World War II judgments at Nuremberg were clear: International law requires states to oppose crimes of war, crimes against peace (aggression) and crimes against humanity. Because these universal requirements are non-negotiable or “peremptory,” they can never be lawfully set aside.
Inevitably, however, “real-world” impediments arise. In the ongoing matter of Russian President Vladimir Putin’s crimes against Ukraine, the United States and NATO are obligated to stand unequivocally with the victim state. Still, by meeting this obligation, these countries could incur serious risks of a wider war with Russia.
How should this delicate balance of obligation and risks be assessed by Washington and NATO? What would be the foreseeable policies of China and North Korea? In a worst-case scenario, wider-war risks would include some form of a nuclear war.
There is more. What are specific United States obligations in this potentially unprecedented conjunction of law and policy? More precisely, what should be done about Nuremberg-level crimes against Ukraine that would be law enforcing but also rational from converging standpoints of peace and justice?
Calculating the risks
Above all, US and NATO remedies would need to calculate variously complex hazards of competitive risk-taking. This means that whatever operational decisions are involved, all competing state parties would strive for “escalation dominance.” In cases where law-enforcement risks and nuclear war risks would overlap or intersect, the results could be “force-multiplying.”
For the United States, international law enforcement is never volitional. As this obligation has been “incorporated” into the law of the United States (see Article VI of the US Constitution and two key cases from the US Supreme Court: Paquete Habana, 1900; and Tel Oren versus Libyan Arab Republic, 1984), remedial action against Russian crimes would support binding expectations of American national law.
Additionally, the Convention on the Prevention and Punishment of the Crime of Genocide (1948) obliges signatories not only to avoid committing genocide, but also to prevent and punish genocidal behavior by other states. Article III of the Convention extends this obligation to acts involving “conspiracy to commit genocide,” “attempt to commit genocide” and “complicity in genocide.” Unambiguously, Putin’s reported kidnapping of over 20,000 Ukrainian children represents a verifiable act of genocide.
Neither international law nor US law advises particular penalties or sanctions for states that choose not to prevent or punish genocide committed by others. At the same time, all states, especially the “great powers,” are bound by a “peremptory” rule defined at Article 26 of the Vienna Convention on the Law of Treaties (1969). This is the perpetual requirement to act in “good faith.”
The “good faith” or “pacta sunt servanda” obligation is derived from an even more basic norm of world law: “mutual assistance.” This norm was identified in classical jurisprudence by eighteenth-century legal scholar Emmerich de Vattel. Later, it was reaffirmed by English jurist William Blackstone, whose Commentaries on the Laws of England became the tangible bedrock of all United States law.
Though the United States could never be held accountable under law for its de facto abandonment of the Ukrainian people, any willful failure to act against Putin in this arena would violate immutable principles of international law.
The anti-genocide regime of international law includes the London Charter of August 8, 1945; UN Charter (1945); Declaration on Principles of International Law Concerning Friendly Relations and Co-Operation Among States in Accordance with the Charter of the United Nations (1970); Affirmation of the Principles of International Law Recognized by the Charter of the Nuremberg Tribunal (1946, 1950); and International Law Commission (ILC) Articles on State Responsibility (2001).
The obligation to prevent genocide
In its landmark judgment of February 26, 2007, “Concerning Application of the Convention on the Prevention and Punishment of the Crime of Genocide” (Bosnia and Herzegovina v. Serbia and Montenegro), the International Court of Justice ruled that all contracting parties have a direct obligation to “prevent genocide.” For still mystifying reasons, the ICJ found it easier to acknowledge this obligation expressis verbis (“with clarity”) than by referencing the corollary legal requirement not to commit genocide.
There is room here for more classical political philosophy. Sixteenth-century Florentine Niccolo Machiavelli combined Aristotle’s plans for a scientific study of world politics with assorted axioms of geopolitics. Machiavelli’s best known conclusion focuses on the timeless dilemma of seeking to practice goodness in an evil world: “A man who wishes to make a profession of goodness in everything,” Machiavelli warns in The Prince, “must necessarily come to grief among so many who are not good.”
If taken too literally, this cynical assessment could lead not only individuals but also states toward an irreversible “state of war.” This trajectory would define a condition of rampant anarchy and disorder, one best clarified by the seventeenth-century political philosopher Thomas Hobbes. In Leviathan, says Hobbes, life must inevitably become intolerable (“everyone for himself”) amid anarchy. He reached this conclusion deductively, and long before nuclear weapons.
Gabriela Mistral, the Chilean poet who won the Nobel Prize for Literature in 1945, wrote that crimes against humanity carry within themselves “a moral judgment over an evil in which every feeling man and woman concurs.”
Now, in continuing to coexist with other states in a self-help or vigilante system of international law, the United States is bound to do whatever is lawfully possible to impede Russia’s genocide and genocide-like crimes against Ukraine, but to accomplish this without expanding the likelihood of superpower military confrontations. Strictly speaking, because these issues are without precedent (sui generis), no pertinent decisions could be science-based.
Still, clear-headed decisions are needed; both American and NATO leaders will need to (1) manage competitive risk-taking with Russia, and (2) prevent any ensuing struggles for “escalation dominance” from becoming nuclear. As a start, strategic planners working to combat Putin’s crimes against Ukraine should make careful distinctions between a deliberate or intentional nuclear war and one that would be unintentional or inadvertent.
Further distinctions will need to be made between nuclear war risks occasioned by accident or a “computer mercenary” and those caused by decision-maker miscalculation. Plausibly, the overriding nuclear war hazard facing the United States and/or NATO over Ukraine is a conflict that no state actually seeks.
Could any conceivable outcome be more bitterly ironic?
The writer is an emeritus professor of international law at Purdue University and the author of many books and scholarly articles on international law, nuclear strategy, nuclear war, and terrorism, including Surviving Amid Chaos: Israel’s Nuclear Strategy (Rowman & Littlefield, 2016; second edition, 2018).