The collective security structure created by the UN Charter is becoming shakier than ever, and two recent trends pose particular challenges to Charter rules on the use of force. The first trend involves a normative shift in understandings of state sovereignty, and the second trend involves improvements in technology--specifically, the rapid evolution of unmanned aerial vehicles, precision weapons, and surveillance technologies. Each trend on its own raises difficult issues. Together, they further call into question international law's ability to meaningfully constrain the use of force by states.
CHANGES IN NORMATIVE UNDERSTANDINGS OF SOVEREIGNTY
The last two decades have seen a dramatic shift away from traditional ideas about state sovereignty. Increasingly, both legal scholars and national and international-level advocates and political decisionmakers have articulated an understanding of state sovereignty as limited and subject to what amounts to de facto waiver. In this vision of sovereignty, a state is required to execute certain responsibilities. If it fails to do so, external actors have a right and/or an obligation to step in themselves to ensure proper execution of these responsibilities.
Versions of these arguments have emerged recently in two very different discourse communities. One is the human rights community, in which this vision of sovereignty is often couched in terms of atrocity prevention and the responsibility to protect. Parallel versions of this argument have also emerged from within the national security community. Here, the argument is generally couched in terms of state duties to prevent the export of terrorism.
The Responsibility to Protect
Let us start with the responsibility to protect. By the beginning of the twenty-first century, the debates in the 1990s over humanitarian intervention had morphed into discussion of the "responsibility to protect," or R2P, a doctrine initially developed by the International Commission on Intervention and State Sovereignty (ICISS). In a 2001 report, ICISS offered a starkly different understanding of sovereignty than that taken for granted prior to World War II:
State sovereignty implies responsibility ... Where a population is suffering serious harm, as a result of internal war, insurgency, repression or state failure, and the state in question is unwilling or unable to halt or avert it, the principle of non-intervention yields to the international responsibility to protect. (1) ICISS was careful to note that the use of military force to protect populations should be a last resort, and that any R2P-based military interventions should be authorized by the Security Council. But ICISS was unwilling to view Security Council authorization as an absolute requirement:
If the Security Council rejects a proposal [to intervene to protect a population] or fails to deal with it in a reasonable time, alternative options ... [include] action within area of jurisdiction by regional or sub-regional organizations under Chapter VIII of the Charter, subject to their seeking subsequent authorization. (2) After all, warned ICISS, if the Council "fails to discharge its responsibility to protect in conscience-shocking situations crying out for action ... concerned states may not rule out other means to meet the gravity and urgency of that situation." (3)
Within a decade, the R2P concept had...