Irreconcilable Differences: The Thresholds for Armed Attack and International Armed Conflict

This Article explores the gap between the definition of armed attack and the threshold for international armed conflict to identify such possible consequences of the different definitions for the application of either or both bodies of law and to consider whether efforts to reconcile the different meanings are feasible and, more importantly, desirable or problematic. The first Part briefly presents the definition of armed attack and the threshold for international armed conflict, with a focus on the purpose of the particular thresholds and definitions for the two terms in order to provide a foundation for the main comparisons and discussion in the rest of the Article. Part II examines the gap between the respective meanings of the two concepts and the potential legal consequences. In particular, this Part analyzes two primary, but opposing, interpretive effects of the gap between the meanings of armed attack and international armed conflict: first, the use of force in situations falling below the threshold of armed attack; and second, the possibility that an international armed conflict could exist without the states engaged in such conflict having the authority to use force against the adversary.

Each of these possibilities raises a red flag within one body of law but at the same time hews closely to the basic concept or goals of the other, raising the question of whether this gap matters and, if so, whether some reconciliation is appropriate. The third Part addresses this final question, that of reconciliation between the two definitions and examines what such reconciliation might look like. More important, attempts at reconciliation could cause a severely damaging blow to one or the other body of law, such that preserving the gap—that is, agreeing to disagree, in effect—is the better course of action.