On September 18, 2001, Congress enacted a joint resolution authorizing the President to, "Use all necessary and appropriate force against those nations, organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons." This authority is referred to as the Authorization for the Use of Military Force (AUMF). Today's hearing will examine the legal basis for the use of military force in accordance with the law of armed conflict, including the use of drones. We have asked our witnesses to help us consider a number of questions including: What is the continuing vitality of the 2001 AUMF a dozen years after its enactment? How will we know when the current conflict is over? Does the AUMF extend to organizations which played no active role in the September 11 attacks and may not have even existed in 2001? Should the AUMF be extended or modified by legislation to cover groups not associated with al Qaeda? What is the legal basis for military action in countries like Yemen and Somalia which are far away from Afghanistan where the September 1 attacks were planned? These and related matters raise challenging questions and there is a wide range of views on the answers.