The Legality of a Pre-Attack Strike on North Korea under International Law
On November 28, 2017, North Korea’s testing of the Hwasong-15 intercontinental ballistic missile (ICBM), which the regime claimed could carry a nuclear warhead capable of targeting the continental United States, marked an important milestone in the regime’s nuclear weapons development program.  This achievement and a recent U.S. intelligence assessment that the regime has produced a miniaturized nuclear weapon for delivery on an ICBM have caused alarm.  While hurdles remain in the regime’s quest to pose an existential nuclear threat to the U.S. mainland, it’s worth asking : could the U.S. legally launch a pre-attack strike against the regime to prevent the materialization of such threat under international law? Under international law, a state’s use of force is governed by Article 2(4) of the UN Charter, which states that “[a]ll Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state . . .”  Yet, Article 51 of the UN Charter recognizes a self-defense exception to the prohibition on use of force: the use of force is permissible “if an armed attack occurs against” the victim state.  It is undisputed that an armed attack legitimizes the use of force in self-defense. Beyond an armed attack, the majority’s interpretation of the law permits self-defense where an attack is yet to occur but is imminent.  This concept, termed “anticipatory self-defense” or “interceptive self-defense,” permits the use of force where an attack “is in the process of being mounted.”    
Outside the parameters of an armed or imminent attack, matters become murkier. While some commentators employ the term “prevention,” others use “preemption,” and still others have not meaningfully distinguished between prevention and preemption. The unifying thread in the debate is that an attack that is neither armed nor imminent is conjectural. 
As such, while the prospect of a North Korea with the nuclear capability to strike the U.S. mainland is frightening, under the current majority view, a nuclearized state that has yet to attack likely does not pass the imminence threshold, under the UN Charter.
Nevertheless, because international law evolves in part through state practice and scholarship, it is important to consider the strategy that might undergird a U.S. decision to launch a pre-attack strike and how the international community might respond. 
As North Korea’s nuclear capabilities become more evident, its intentions remain unclear. Does the regime intend to use its nuclear capabilities defensively, namely, to deter a U.S. attack, or does it intend to use such capabilities offensively, to gain greater clout in East Asia?  The materialization of such threats could, in the near future, be considered imminent threats that legitimize a pre-attack strike under international law.
This post is a student blog post and in no way represents the views of the Fordham International Law Journal.