Repeals the affirmation in the National Defense Authorization Act for Fiscal Year 2012 that the President's authority under the Authorization for Use of Military Force (P.L. 107-40) includes the authority for the U.S. Armed Forces, pending disposition under the law of war, to detain persons who: (1) planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored those responsible for those attacks; or (2) were a part of or substantially supported al-Qaeda, the Taliban, or associated forces engaged in hostilities against the United States or its coalition partners, including any person who has committed a belligerent act or has directly supported such hostilities in aid of such enemy forces.