Efforts to limit the proliferation of nuclear weapons and nuclear-weapons-related technology have increasingly involved economic, technological, and military forms of coercion implemented in an environment of low-level conflict. Coercive counterproliferation measures have included a range of actions, including targeted economic sanctions, industrial sabotage, cyber attacks, targeted killings, and military strikes. While the nonproliferation obligations of states are well-established under relevant treaties, state practice, and the international monitoring system of the International Atomic Energy Agency (IAEA), norms relating to the enforcement of those obligations are not clearly defined in legal instruments. This Article reviews the legality of prevention and enforcement measures through the institutional framework of the global nonproliferation regime, considering the tensions between that framework and a range of cross-cutting disciplines of international law, including the law of nonforcible intervention, state responsibility, and the law of force. The Article advocates the continuing development of consistent technical criteria to determine proliferation risk at the institutional level of the IAEA monitoring system, and the prioritization of that system in the enforcement of nonproliferation obligations. It addresses the key legal issues associated with the full range of counterproliferation prevention and enforcement options, providing a comprehensive framework to facilitate the refinement of legal norms guiding global counterproliferation efforts.
TABLE OF CONTENTS I. INTRODUCTION II. DEFINING THE PROBLEM: WHAT IS PROLIFERATION AND WHEN IS IT ILLEGAL? A. Proliferation as an Internationally Wrongful Act B. Moving Toward a Definition of Proliferation III. THE IAEA SAFEGUARDS SYSTEM: A FRAMEWORK FOR PEACEFUL USES A. Comprehensive Safeguards Agreements B. The Model Additional Protocol C. New Facility Notification and Code 3.1 D. Weaponization Activities Not Involving Nuclear Material E. Assessing the Credibility of Information Sources F. The Analytical Framework G. Assessing Capabilities: Technology and Intention IV. PROLIFERATION QUANDARIES: PROMINENT CASE STUDIES A. North Korea: Moving Beyond the Threshold B. Iran: The Problem of Ambiguity C. Reconciling Treatment of Non-NPT States with a Prevention Regime V. ECONOMIC COUNTERPROLIFERATION MEASURES A. Extraterritoriality: Jurisdictional Impediments to Effective Prevention B. Crippling Sanctions: Approaching a Pre-Force Maximum VI. INTERFERENCE MEASURES: INTERDICTION AND CYBER ATTACKS A. Interdiction: State Action and International Law 1. Cuban Missile Redux 2. Roving Police Authority 3. Interdiction and Force B. The Advent of Low-Level Conflict: Cyber Attacks and Sabotage 1. Cyber Measures and the Use of Force 2. Cyber Measures, Intervention Law, and State Responsibility VII. PREVENTIVE FORCE AND NONPROLIFERATION LAW VIII. CONCLUSION: ALL ROADS LEAD BACK TO EFFECTIVE MONITORING IN A COOPERATIVE POLITICAL ENVIRONMENT I. INTRODUCTION
Since the earliest days of atomic energy, the international community has sought to find ways to prevent the use of that technology in nuclear weapons development. (1) In 1963, President John F. Kennedy predicted that fifteen to twenty-five states would have nuclear weapons by the 1970s. (2) Since that time, five nations legally qualified to join the Nuclear Non-Proliferation Treaty (3) (NPT) as nuclear-weapon states, another three states that never joined the Treaty are generally understood to possess nuclear weapons, and another state, the Democratic Republic of North Korea (DPRK), developed nuclear weapons after withdrawing from the Treaty. The success of the global nonproliferation regime has largely exceeded President Kennedy's expectations, though challenges remain. Preventing the diversion of nuclear technology to military uses has and will remain a top priority for the international community, requiring continued consideration of the legality of related measures of prevention.
Tense historical moments relating to the deployment and spread of nuclear weapons range from the Cuban Missile Crisis, to Israel's attack on Iraq's Osirak reactor, to the First and Second Gulf Wars in Iraq, to the ongoing standoffs with the DPRK and Iran. In more recent years, various measures have been taken to target alleged nuclear weapons development programs, including air strikes against Syria and various forms of sabotage against Iran. (4) In the midst of these events, the International Atomic Energy Agency (IAEA) endeavors to maintain an effective and globally applicable monitoring system to verify that atomic energy is used for exclusively peaceful purposes. As rhetoric heats up over possible military dimensions of Iran's nuclear energy program, and with some degree of low-level conflict underway, questions of the legality of measures to prevent the spread of nuclear weapons gain renewed prominence. Counterproliferation prevention and enforcement measures addressed in this Article include peaceful measures effected through diplomatic channels, as well as coercive measures, including economic sanctions, sabotage, and force.
The global nonproliferation regime comprises both cooperative and coercive legal and political mechanisms, including the NPT, the IAEA's system of safeguards, the Chapter VII authority of the UN Security Council, and the sovereign authorities of individual states. The legal core of the nonproliferation regime is the NPT, under which member states that did not possess nuclear weapons as of January 1, 1967, (5) agree not to use nuclear technology for military purposes in exchange for established rights to receive and use nuclear technology for peaceful purposes. Non-nuclear-weapon states parties to the NPT agree to the application of IAEA "safeguards" to their peaceful nuclear energy programs, (6) which are agreements between the IAEA and states designed to facilitate the auditing, monitoring, and inspection of nuclear energy programs. Under this system, it is the task of the IAEA to provide credible assurances that nuclear energy is used for exclusively peaceful purposes. The application of consistent criteria to assess proliferation risk and safeguards compliance is critical to this task.
The IAEA safeguards system consists of (1) safeguards agreements implemented in accordance with relevant treaties,7 most notably the NPT and Nuclear Weapon Free Zone Treaties (NWFZ), (8) (2) the Statute of the IAEA, to the extent it is incorporated into safeguards agreements, and (3) practices of the IAEA that have evolved in the implementation of safeguards agreements. As the principal international agency responsible for monitoring the peaceful uses of nuclear energy, the IAEA plays a central role in verifying that states adhere to their nonproliferation obligations through its safeguards system. Problems arise when states elude, or are perceived to elude the verification authority of the IAEA's monitoring system. When questions of noncompliance with safeguards agreements arise, the IAEA may impose a limited range of remedial measures, including special inspections, denial of assistance, or suspension of membership. (9) The IAEA Statute and its safeguards agreements generally require that instances of noncompliance be reported to the Security Council. (10)
When issues of possible noncompliance with safeguards agreements are referred out of the IAEA, the Security Council assumes legal responsibility for determining appropriate prevention and enforcement steps. While state compliance with safeguards agreements is a key factor in determining whether a state is complying with legal nonproliferation obligations, legal determinations of NPT noncompliance are not directly within the province of the IAEA. The global nonproliferation regime relies on a broader framework for the development of nonproliferation norms. Specific legal authority for interpreting the NPT may rest with the NPT review conference of states parties 11 or under limited circumstances through a judicial forum such as the International Court of Justice. (12) Security Council and state practice may provide evidence of internationally agreed interpretations or even customary law. The development of nonproliferation norms thus takes place in a mixed law and policy framework, involving the administration of voluntarily entered legal agreements and the enforcement of those agreements through a collective security apparatus. Although nuclear law is highly specialized, the employment of coercive measures to enforce nonproliferation obligations implicates a range of crosscutting international law disciplines, including the law of international sanctions, use of force law, and the law of intervention.
Measures aimed at preventing the spread of nuclear weapons need not be coercive. The optimal mechanism to resolve any doubts about possible military dimensions of a state's nuclear energy program is through the IAEA's safeguards system. When the IAEA can provide credible assurances that a state's nuclear energy program is used for exclusively peaceful purposes, coercive measures to prevent the acquisition of nuclear weapons are wholly unnecessary. Even in cases when the IAEA refers a state to the Security Council for noncompliance with safeguards agreements, the suspect state may begin to resolve proliferation concerns directly with the IAEA, by fully participating in the safeguards system. (13) It is important in this context that diplomatic efforts to address proliferation-related crises permit a rolling back of coercive measures (e.g., sanctions) in exchange for cooperation as a means to avoid vicious circles of crisis escalation. (14) The technical verification role of the IAEA under its safeguards system provides a primary mechanism for preventing the spread of nuclear weapons, the effective operation of which should be the aim of any prevention and...