Often it is assumed, wrongly, that international agreements in treaty form are the only valid source of international legal obligations. In some respects, written agreements, duly ratified, are preferable sources of guidance as to the requirements of international law. Written formulations can be more explicit and elaborate with respect to a given pattern of conduct. Furthermore, as far as governments are concerned, there is a tendency to accord greater respect to those legal obligations to which consent in explicit and constitutional form has been given, especially if the negotiation and ratification processes are recent, most particularly within the life span of the governmental leadership currently in power.
There are also limitations to the view that treaty rules are the only genuine source of international law, or even the more moderate view, that these formulations of law are necessarily the best source. Some general norms have not been reduced to treaty form. In other instances, some states are not bound by treaties, having withheld their consent. In still other instances, the content of the treaty rules is vague or subject to contradictory formulations, especially so in relation to the early efforts to codify war and peace, quite dramatically superseded by modern methods and styles of warfare, as well as by new military technologies and weapons systems. This Tribunal has applied international law by taking full account of both customary and treaty rules of international law.
There is an obvious problem of application with respect to nuclear weapons. The nuclear weapons states have so far refrained from entering into any serious negotiations towards a treaty, or even a declaration, acknowledging the unlawfulness of threats or uses of nuclear weapons. Such a deficiency is obviously not an oversight. Hence, to derive applicable rules of international law that add up to an unconditional prohibition of the use of this weaponry is bound to collide with the official security policies of major states, and to challenge the legitimacy of weapons capabilities and bureaucracies that command control over vast allocations of resources.
In the summary of Evidence before the Tribunal (see Chapter 2 - the applicable Treaty rules are considered in detail, and are anticipated here). There are, however, certain broad efforts to reduce to treaty form agreed standards of behaviour that seem crucial here, especially because their generality suggests a relevance to any assessment of the lawful status of nuclear weapons and tactics. The important general treaties in this area were formulated at the Hague in 1899 and 1907 in a series of comprehensive conventions that summarized the pre-World War I levels of agreement as they existed between the governments playing a leading role in international life. The goal was not to eliminate war, but to regulate its conduct in accordance with the customary principles briefly set forth in the preceding paragraph. Especially important was the broad imperative embodied as a common article in the various Hague Conventions of 1899. Article 22 in the Annex to the Hague Convention IV (Regulations Respecting the Laws and Customs of War on Land) states:
"The right of belligerents to adopt means of injuring the enemy is not unlimited."
The apocalyptic implications of a major reliance on nuclear weapons gives this provision an obvious orienting relevance.
Also critical was the celebrated "de Martens clause" (named after the Belgian jurist Feodor de Martens) inserted in the 1907 Hague Conventions+ :
"Until a more complete code of the laws of war has been issued, the high contracting Parties deem it expedient to declare that, in cases not included in the Regulations adopted by them, the inhabitants and belligerents remain under the protection and the rule of the principles of the law of nations, as they result from the usages established among civilized people, from the laws of humanity, and the dictates of the public conscience."
This resolve in international treaty law to base permissible action expressly on normative traditions and upon conscience is a significant basis of encouragement for the inquiry of this Tribunal. The "de Martens Clause" definitely refutes the ultra-statist view that everything is permitted if it has not been expressly renounced by a formal manifestation of governmental authority.
International treaty law has successfully achieved a very widely endorsed prohibition of poison as a weapon and tactic of war. To date the most important treaty instrument, adopted in response to the menace of poison gas revealed in the trenches of World War I, is the 1925 Geneva Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous and other Gases, and of Biological methods of Warfare. At present a variety of negotiations and proposals seek to extend in more detailed form this prohibition on toxic weaponry. Unlike in the case of biological weapons, the current treaty law prohibits threat and use, but not development and possession. Hence, a deterrent approach to chemical weapons is not per se prohibited under contemporary international law.
Another significant line of effort in treaty law concerns the discretion to initiate war via acts of aggression. In the 1928 Pact of Paris, war is outlawed as an instrument of national policy, and legitimate force confined to circumstances of self-defence. This treaty norm provided a major basis for the war crimes prosecution at Nuremberg and Tokyo after World War II, giving rise to the category of offence known as "Crimes against Peace" . The United Nations Charter, a multilateral treaty, carries forward in Articles 1(4), 33, and 51 the basic notion that there is no legal pretext for recourse to force in international relations except in self-defence against a prior armed attack. There is some controversy among international law specialists as to whether patterns of state practice have so consistently ignored this constraining legal framework as to suspend, or to draw into question, its continuing validity. At stake in the nuclear weapons setting is the critical issue as to whether the design and development of first-strike weaponry and supporting doctrine amounts to a per se act of aggression, as well as rendering officials liable for crimes against the peace. At Nuremberg it was definitely decided that planning for aggressive war is itself a crime even if the aggressive policy is never consummated. Does this prohibition pertain to those allegations that certain classes of nuclear weapons systems have first-strike properties and roles?
Another major treaty instrument was the Genocide Convention of 1948 that established the criminality of any course of deliberate state policy that intends to destroy, in whole or part, national, ethnic, religious, or racial groups. Nuclear weapons are aptly described as weapons of mass destruction, and their use in any sustained manner, seems genocidal in impact, as well as ecocidal. Indeed, the grim magnitude of such destruction suggests that beyond genocide lies the result of omnicide. Given the inability to apprehend after the event, this Tribunal seeks to examine whether the genocidal propensities of nuclear weapons, and doctrines governing their use, do not constitute sufficient ground to find governments and their leaders guilty of intentional violations of the Genocide Convention.
Ever since the nineteenth century there has been an effort complementary to that of the Law of the Hague dealing with weapons and tactics to codify international humanitarian law applicable during wartime, sometimes known as the Law of Geneva, because so many of the main treaty instruments were negotiated and signed at Geneva. The main elements of the Law of Geneva are the four Geneva Conventions of 1949 - for the protection of land forces, of sea forces, of prisoners of war, and of civilians. The attempt of these agreements is to give concrete application to the Principle of Humanity, by imposing obligations on belligerent states to respect the sanctity of such things as hospitals, cultural monuments etc., and to avoid any military action against the sick and wounded, or against those of the enemy who have laid down their arms and become prisoners of war.
These treaty rules suggest levels of respect for the limits of warfare that seem utterly inconsistent with any use of nuclear weapons. Again an issue for this Tribunal is whether this body of law can be considered superseded by contrary patterns of state practice. Efforts to extend this humanitarian approach to the explicit circumstances of nuclear weaponry have not been successful as yet. Both the United States and Britain made it clear that their participation in the negotiation of the Geneva Protocols I and II in 1977, to modernize the 1949 Conventions, was taking place on the assumption that nuclear weapons , and were not to be considered subject to the treaty norms, even in relation to Article 35 which explicitly deals with new weapons and methods of warfare. Is such an exclusion effective? This question is important for this Tribunal to address in its Judgment.
A final source of treaty guidance for this Tribunal arises from the legal duty imposed on the governments of nuclear states by such arms control agreements as the Limited Test Ban Treaty of 1963 and the Non-Proliferation Treaty of 1968, to negotiate in good faith an end to the nuclear arms race and to establish by stages or any reasonable process, secure arrangements for general and complete disarmament. This Tribunal needs to determine whether the failure to accept proposals for a comprehensive test ban and the continued preparation for nuclear warfare, including the development of new weapons systems with first-strike propensities, amount to violations of international treaty obligations.
+ This is from the preamble to the 1907 Hague Convention IV Respecting the Laws and Customs of War on Land.