While the world mourned in the immediate aftermath of the September 11 attacks on the World Trade Center and the Pentagon, an international legal response was sculpted in the corridors of the UN Security Council, NATO, and the US Congress. This response was subsequently presented to the world as a coherent package termed the war against terrorism. Critiques of the package and attempts to understand the reasons for the brutal attack were cast aside as philosophical and inappropriate in a time of crisis. The international community agreed to support every action taken under the umbrella of this new war. In the past, similar periods of crisis have served as foundational moments in international law. Yet in the months that followed the September 11 attacks, the reputation of international law remains suspect, if not in tatters. The unilateral power grabs taken under the guise of a fragile international consensus and the supersonic speed with which international institutions responded to the attacks set alarming precedents with profound consequences.

The responses to the September 11 attacks have left many scholars with a sense of discomfort and even frustration. The attacks exposed a gaping hole in the field of international law. The acts were criminal, but they also constituted a warlike assault on the United States. International law, which has traditionally been associated with relations between state actors, was confronted with an enigma, an attack by a non-state actor on a sovereign nation. Non-state actors, whether market participants or international trading companies, have long been significant players in the international arena and brought many unresolved challenges to the structure and relevance of international law. Today, some non-state actors, such as terrorist networks and international financial institutions, have acquired a supranational status and have exposed the limited utility of international legal doctrine that remains unresponsive to the normative challenges emerging from today’s transnational realities. The response to the September 11 attacks therefore raises questions about the legitimacy and effectiveness of mainstream international law in a transnational world.

The Rule of Law

In the immediate aftermath of September 11, there were two competing narratives that found expression in the international arena. One concerned the rule of law and the other concerned the rule of terror or violence. On September 12, the UN Security Council unanimously adopted a resolution declaring that it “regards [the attacks], like any act of international terrorism, as a threat to international peace and security.” The Council further called “on all states to work together urgently to bring to justice the perpetrators, organizers and sponsors of these terrorist attacks and stressed that those responsible for aiding, supporting or harboring the perpetrators, organizers and sponsors of these acts will be held accountable.”

The Security Council thus set the stage for ordering the imposition of sanctions (Article 41) or use of force (Article 42) under Chapter VII of the UN Charter. The resolution obliges the Council to take steps to restore international peace and security. The Council had previously resorted to sanctions in 1999 and 2000, establishing a ban on air travel, freezing funds, and imposing an arms embargo on the Taliban regime in Afghanistan. These measures were enacted when the Taliban failed to comply with resolutions requiring it to close down terrorist training camps and surrender Osama bin Laden and others for trial in connection with the 1998 bombings of US embassies in East Africa. After September 11, the United States declared that it had credible evidence that the attacks were the work of Osama bin Laden and the Al Qaeda network. On September 28, the Security Council adopted a resolution requiring all states to cease financing of terrorist operations and to “deny safe haven” to terrorists.

In the view of some scholars, the bombing of Afghanistan, ostensibly part of the war against terrorism, only augments the rule of terror. The Security Council resolution of September 12 does not itself authorize military action but refers only to the Security Council’s “readiness to take all necessary steps to respond to the terrorist attacks of 11 September 2001 and to combat all forms of terrorism.” The preamble of the resolution recognizes that there is an “inherent right of individual or collective self-defense in accordance with the Charter.” Yet the invocation of the right of self-defense against an “armed attack” under Article 51 of the UN Charter has traditionally been understood to concern relations of states and in any event applies only “until the Security Council has taken measures necessary to maintain international peace and security.” The September 28 resolution calls for all states to ooperate “to take action against perpetrators.” However, since there has been no clear statement from the Security Council authorizing military operations, the mandate should have been construed as being restricted to police action in cooperating countries to bring such persons to justice. Despite the clear constraints imposed on the use of military force, the United States has taken military action to avenge the attacks of September 11 with the acquiescence of its NATO allies. The speed with which the rule of international law was reshaped into a tool for the war against terrorism has exposed its vulnerability to political capture. The edifice erected for responding to the September 11 attacks has created a ripple of discontent and discomfort over the legitimacy of the international legal process as well as the effectiveness of international law. Another concern is that there has been a lack of interrogation, critique, and resistance to the use of force, even after the requirements of “necessity, proportionality, and discrimination” prescribed by international law have been abrogated.

The Rule of Ambiguity

Any military action resorted to under international law must meet certain legal requirements—including necessity, proportionality, and discrimination. The principle of necessity requires that the least violent course of action be taken to prevent further attacks and bring planners and perpetrators to justice. Proportionality requires that military action must not be excessive in relation to the initial attacks and to the action’s objectives. And discrimination requires that civilians not be attacked and that they not be disproportionately injured or killed by attacks on legitimate military targets. Some of the other constraints imposed on military action include taking care not to inflict unnecessary suffering on combatants, harm neutral nations, or cause widespread and severe damage to the environment. Not only are these requirements imposed by international treaty and custom, they are also accepted in the US military manuals on the law of war and rules of engagement and are recognized by the United States and the United Nations as binding law governing their conduct of military operations.