Twelve years ago today, in the immediate aftermath of the September 11 attacks, President Bush signed the Authorization for Use of Military Force (AUMF) into law. This document, passed with virtually unanimous support in both houses of Congress, has provided the primary legal basis for the wide-ranging war on terror that the United States has waged. Its main clause authorizes 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, in order to prevent any future acts of international terrorism against the United States by such nations, organizations or persons.
Since its passage, this law has underpinned the war in Afghanistan, the practice of indefinite detention, and the campaign of targeted killings in Pakistan, Yemen and elsewhere. Congress and the courts have interpreted the law as applying to authorize force against the Taliban, Al Qaeda and their “associated forces,” although that phrase itself does not appear in the text of the AUMF.