International Security and the Law: Is International Law Still Relevant During Armed Conflict?

International law is and should remain relevant during armed conflict. In this chapter, I focus on two principal themes: the right of a state to use armed force in international relations, and the law applicable to the parties to an armed conflict once it has begun. The hallowed Latin tags are ius ad bellum and ius in bello. I conclude by examining the broader implications of international law in conflict, and address the question of whether new challenges, especially since the vile atrocities of 11 September 2001, call for new laws.