The Authorization for Use of Military Force (AUMF), Pub. L. No. 107-40, 115 Stat. 224 (2001), enacted shortly after the terrorist attacks of September 11, 2001, constitutes the main source of congressional authorization for the war on terror. The AUMF grants the President the authority to use all “necessary and appropriate force” against those whom he determines “planned, authorized, committed or aided” the September 11th attacks, or who harbored those persons or groups.
The AUMF beings with a preamble, which emphasizes the "acts of treacherous violence" committed on September 11, the "continue[d] . . . unusual and extraordinary threat" posed by such terrorism, and the President's "authority under the Constitution to take action to deter and prevent acts of international terrorism against the United States."
Section 2(a) contains the AUMF's main grant of authority:
[T]he President is authorized 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, in order to prevent any future acts of international terrorism against the United States by such nations, organizations or persons.
Section 2(b) provides that the AUMF satisfies the requirement under § 5(b) of the War Powers Resolutions for a specific statutory authorization while at the same time leaving the War Powers Resolution unaltered.
The Role of the AUMF
In Hamdi v. Rumsfeld, the Court decided that detention of enemy combatants for the duration of hostilities is an exercise of “necessary and appropriate force” that Congress authorized the president to use under the AUMF. After Hamdi, the AUMF became the main source of presidential authority to detain enemy combatants in Guantanamo Bay, Cuba.