Editor’s Note: This Q&A is part of a series following the 4th Annual Stockton Center Law of Armed Conflict Conference, Russia-Ukraine: Full-Spectrum Conflict and the Law, held at the U.S. Naval War College in Newport, Rhode Island over December 13-15, 2022 and co-sponsored by the Norwegian Defence University College and the Swedish Defence University. While the conference was held under the Chatham House Rule, several of the expert participants are taking part in a public question and answer series to illuminate some of the pressing issues addressed during the conference sessions that merit further analysis. The first Q&A in this series is available here.

Q:  Are Methods of Naval Warfare at Risk Under “Qualified” Neutrality?  

Major W. Casey Biggerstaff:  In the wake of Russia’s renewed invasion of Ukraine, several States have provided Ukraine with a remarkable amount of military aid and assistance not seen since World War II. Among the several international legal issues raised by this support is the decades-old debate over whether it violates the law of neutrality. The dispute generally revolves around whether neutral obligations in the classic sense should or should not apply in the post-U.N. Charter era. The issue is critical since breaches of international law (or “internationally wrongful acts”) would open the door to Russian countermeasures (see Draft Articles of State Responsibility, arts. 2, 22, and 31) or in a narrow set of circumstances under traditional neutrality law, the use of force by Russia to prevent further neutrality violations, including those occurring on neutral territory (see U.S. DoD’s Law of War Manual, § 15.4.2; the current availability of which is contested, see Bothe ¶ 28; Davis).

While much of the debate has centered on the various legal bases set forth in defense of neutrality’s variants, evaluating their practical implications is also critical. In private discussions with fellow international law practitioners, for instance, some have questioned whether any reluctance to embrace so-called “qualified” neutrality, which justifies the provision of military aid under certain conditions, is due to concern that its second-order effects could limit conventional methods of war that indirectly affect neutral States. Specifically, as the vast majority of material aid (and global commerce generally) travels by sea, they question whether the belligerent rights of blockade and “visit and search” would continue to remain available to belligerents labeled as aggressors by other States under a qualified neutrality regime. A blockade is an operation that restricts enemy and neutral ships or aircraft from entering or exiting specified areas (e.g., enemy ports, airfields, etc.) (Commander’s Handbook on the Law of Naval Operations, 7.7.1). Visit and search refers to the method by which a belligerent verifies the character of merchant ships (enemy or neutral) and their cargo (contraband or noncontraband) encountered outside neutral territory (7.6). To understand what’s at stake, however, it is necessary to summarize the debate’s various positions first.

Proponents of adhering strictly to classic (or “absolute”) neutrality rules, such as those outlined in the 1907 Hague Conventions V and XIII Respecting the Rights and Duties of Neutral Powers and Persons in Case of War on Land and in Naval War, argue that certain types of support violates neutral States’ legal obligations of abstention (or non-participation) and impartiality and thereby constitute a breach of international law.

For instance, with respect to the $32.2 billion in security assistance the United States has provided Ukraine since February 24, 2022, Hague Convention XIII unequivocally states “the supply, in any manner, directly or indirectly, by a neutral Power to a belligerent Power, of war-ships, ammunition, or war material of any kind whatever, is forbidden” (art. 6). By this approach, it is legally irrelevant, at least for purposes of assessing neutral duties, that Ukraine is the victim of Russian aggression. Of course, the same would be true of Iran’s and other States’ provision of weapons to Russia, which violates other international legal obligations as well given Russia is clearly the aggressor.

On the other side of the debate, advocates of various forms of qualified (or “benevolent”) neutrality claim (e.g., here, here, and here) that the traditional treaty and customary rules referenced above have been displaced, albeit to varying degrees, by the 1928 General Treaty for Renunciation of War As an Instrument of National Policy (or Kellogg-Briand Pact) and the collective security regime established by the 1945 U.N. Charter, if they aren’t obsolete altogether (see generally H. Lauterpacht, 650-51).

Under this view, States supporting Russia with military aid are still violating neutrality law. By contrast, those States supporting Ukraine as the undeniable victim of Russia’s unprovoked aggression are not because the instruments cited above “destroyed the historical and juridical foundations of the doctrine of neutrality conceived as an attitude of absolute impartiality in relation to aggressive wars” (U.S. Att’y Gen. Jackson, Speech to IABA, Mar. 27, 1941). Thus, while nuanced variations of the argument exist, they generally share a common understanding that classic neutrality rules do not apply to State aid and assistance provided to a victim-State such as Ukraine.

While the debate over the legal basis for qualified neutrality is far from settled, what is less clear is what effect, if any, it would have on how a belligerent State can interact with neutral States supporting the former’s adversaries. In other words, if qualified neutrality is indeed correct as a matter of law, may belligerent States still execute blockades or exercise their right of visit and search if they are the aggressor in the conflict? If not, that consequence would have severe implications for the law of naval warfare.

Shortly after the Kellogg-Briand Pact entered into force, the International Law Association proposed in its 1934 Budapest Articles of Interpretation that, in the event an aggressor State violates the Pact, other States should, inter alia, “Refuse to admit the exercise by the State violating the Pact of belligerent rights, such as visit and search, blockade, etc.” (here at n. 4). This could account for some suspicion that naval methods of warfare may be at risk under qualified neutrality. However, the Articles met with initial criticism before World War II’s outbreak, including by a leading advocate of qualified neutrality, and even those States that ultimately adopted a policy of qualified neutrality during the war do not appear to have embraced the cited proposal in their practice.

Following World War II and the adoption of the U.N. Charter, relatively few armed conflicts between States (neutrality law does not apply to non-international armed conflicts) have arisen, making it challenging to assess current international consensus. The issue is further clouded by the fact that some analysts—wrongly, in my view—have increasingly called into question the military effectiveness of, in their opinion, outdated naval warfare methods such as blockades. For instance,

Naysayers argue that the world has changed in several critical ways since World War II, making a return to that form of commerce warfare highly unlikely. They point to globalization, the volume of mercantile traffic, the relatively small size of modern navies, the complexity of [the] modern commercial shipping business, and the increase in alternative trade infrastructure that is relatively immune to maritime trade warfare (Squires at 4).

Nevertheless, if customary international law has indeed evolved into qualified neutrality, in my assessment, there is little empirical evidence that the use (by aggressors) of blockades or visit and search as lawful methods of naval warfare have been adversely impacted, at least not in the limited number of international armed conflicts that have included a significant maritime component. For example, at the war’s outset, Russia declared “restricted zones” in the Black Sea and Sea of Azov. While critics have branded the de facto blockade as illegal, they did so because Russia’s actions failed to satisfy all the requirements for imposing a lawful blockade (authority, notification, effectiveness, impartiality, limited scope; see Commander’s Handbook, 7.7.2), not because the operation was unavailable to Russia as a matter of law as an aggressor-State (see Kraska at 553-54; Fink). Similar criticism has befallen Russia’s indiscriminate attacks on neutral merchant vessels inside the restricted zone, which have been condemned not because of Russia’s loss of legal rights, but because “there [was] no indication that any of these vessels were engaged in activities that would render them subject to capture or attack by either of the belligerents” (Pedrozo, 32).

Moreover, in my view, qualified neutrality would not disturb longstanding methods of waging war at sea because qualified neutrality, at least in its original formulation, is not inherently incompatible with absolute neutrality; qualified neutrality is a neutral State’s option, not its duty (H. Lauterpacht, 651; Jackson, 9-10). As the current conflict demonstrates, even if some States discriminate against a perceived aggressor, that does not mean all States must do so. This coexistence counsels against the conclusion that methods of warfare would be affected by how individual States react to the conflict.

Further, even if qualified neutrality was exclusively applicable, I am not persuaded, at least not as a matter of law, that an aggressor should not be able to interdict and capture arms or other commerce susceptible to the enemy’s use in warfare (contraband) just because qualified neutrality precludes the wrongfulness of a neutral State supplying them. At its core, qualified neutrality is premised upon the fact that war as an instrument of national policy is now generally illegal (Jackson, 15). But in the decades since the Pact and Charter were adopted, the question of when States may resort to force has had little, if any, bearing on how they may do so. In other words, qualified neutrality alters the duties owed to an aggressor, not the nature of the support provided to the victim. In my view, absent a clear indication in State practice to the contrary, it should not effectively transform what would otherwise be contraband into “free goods” immune from capture. I don’t believe the law has developed that far. Thus, there is no reason to suspect, at least not under the current state of affairs, that qualified neutrality would proscribe methods of naval warfare that have existed for centuries.

IMAGE: Russia’s navy ships and helicopters take part in a military exercise called Kavkaz (the Caucasus) 2016 at the coast of the Black Sea in Crimea on September 9, 2016.  (Photo by VASILY MAXIMOV/AFP via Getty Images)