In response to the September 11, 2001, terrorist attacks against the United States, Congress enacted the Authorization for Use of Military Force (2001 AUMF; P.L. 107-40 ; 50 U.S.C. §1541 note) to authorize the use of military force against those who perpetrated or provided support for the attacks. President George W. Bush identified Al Qaeda as the group that carried out the attacks, and the Taliban, then in control of the governance of Afghanistan, as harboring Al Qaeda within the territory of that country. Under the authority of the 2001 AUMF, in October 2001 President Bush sent U.S. Armed Forces to Afghanistan to conduct military operations "designed to disrupt the use of Afghanistan as a terrorist base of operations and to attack the military capability of the Taliban regime." More than 13 years later, in December 2014, President Obama declared the end of the combat mission in Afghanistan. Despite this announcement, U.S. Armed Forces remain in Afghanistan and are reportedly authorized to target Al Qaeda and the Taliban. As armed conflict against Al Qaeda and the Taliban has progressed, and U.S. counterterrorism strategy has evolved, U.S. use of military force has expanded outside Afghanistan. After the U.S. invasion of Afghanistan, many members of Al Qaeda moved out of the country and into Pakistan. In response, the United States has conducted unmanned aerial vehicle (UAV) missile strikes against Al Qaeda and Taliban targets in Pakistan. The United States has identified other groups in the Middle East and Africa that it considers "associated forces" of Al Qaeda, that is, organized forces that have entered alongside Al Qaeda in its armed conflict with the United States and its coalition partners. The United States has used force against these Al Qaeda associates in a number of other countries, including Yemen, Somalia, Libya, and most recently, Syria. In addition, the President has relied in part on the 2001 AUMF as authority for his campaign against the Islamic State (also known as ISIS or ISIL) in Iraq and Syria, and against the Khorosan Group of Al Qaeda in Syria. Since 2001, counterterrorism activities involving deployment of U.S. Armed Forces, if not always the use of military force, have steadily increased, taking place in countries around the world, although it is not clear whether the 2001 AUMF has provided authority for these activities. The 2001 AUMF, as many have argued and the executive branch has agreed, does not seem to authorize all uses of military force in furtherance of U.S. counterterrorism objectives. Although some presidential reporting to Congress suggests a wide interpretation of the scope of 2001 AUMF authority, the Obama Administration, as recently as May 2014, has stated that the 2001 AUMF authorizes only those uses of military force against Al Qaeda, the Taliban, and their associated forces, and, when such actions are taken outside of Afghanistan, only in cases of imminent threat of attack against the United States. Because the 2001 AUMF covers only some uses of military force to counter terrorist threats, other legislation and presidential powers under Article II of the Constitution provide authority to carry out U.S. counterterrorism activities globally. Some observers and Members of Congress have argued that the 2001 AUMF, focused as it is on those who perpetrated and supported the September 11, 2001, terrorist attacks, is outdated and should be repealed, as it has been stretched and perhaps distorted to fit uses of force that were not contemplated when the 2001 AUMF was enacted. Others assert that the 2001 AUMF should be updated to reflect the evolution of the terrorist threat since 2001 and the continued need to authorize the use of military force against this threat, perhaps with greater oversight and procedural requirements from Congress. The Obama Administration has indicated its willingness to address concerns about the 2001 AUMF and continued uses of military force in support of counterterrorism goals, in the past arguing that the 2001 AUMF must remain in force until combat operations end in Afghanistan. By the end of 2014, the United States and Afghanistan had finalized a bilateral security agreement, and the combat mission in Afghanistan had been declared complete. The Obama Administration, however, still finds itself relying on 2001 AUMF authority not only for continuing U.S. military operations in Afghanistan, but also for beginning a new campaign against the Islamic State in Iraq and Syria, and possibly expanding operations to other countries if the Islamic State or Al Qaeda groups or associates effectively expand their reach and pose a threat to U.S. national security and interests. The President, in his February 11, 2015, letter to Congress concerning his draft proposal for a new authorization for use of military force against the Islamic State, stated, "I remain committed to working with the Congress and the American people to refine, and ultimately repeal, the 2001 AUMF." In the face of these issues, Congress has for several years considered a number of legislative proposals to change the authority in the 2001 AUMF, the manner in which it is used, and the congressional role in its oversight and continuing existence. This process has continued in the 114 th Congress, and deliberations over the future of the 2001 AUMF have become entwined with consideration of proposals to enact a new AUMF to respond to the actions of the Islamic State in Iraq and Syria. Generally considered a broad authorization for the President to use military force against the terrorist threat posed by Al Qaeda after the September 11, 2001, terrorist attacks, the 2001 AUMF is nonetheless limited in scope, targeting only those who perpetrated or supported those attacks. Because of this limitation, the two most recent Administrations have instituted procedures to determine which actors are lawful targets of military force and in which parts of the world such force might be used under different circumstances. The effect has been U.S. uses of military force or other deployment activities in several countries, and varying as to type and scope. Shortly after the September 11, 2001, terrorist attacks on the United States, Congress enacted and President George W. Bush signed into law the 2001 AUMF. The 2001 AUMF authorizes the President to use U.S. Armed Forces to combat the nations, groups, and individuals who perpetrated the September 11, 2001, attacks and those who harbored such perpetrators. Section 2(a) of the 2001 AUMF authorizes the use of force in response to the September 11 attacks: Resolved by the Senate and House of Representatives of the United States of America in Congress assembled, . . . . sec. 2. authorization for use of united states armed forces. (a) In General.—That the 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. The authorizing language is broad in its scope concerning prevention of any future acts of terrorism perpetrated against the United States, but is circumscribed by authorizing the targeting only of those nations, organizations, or persons involved in perpetrating the September 11 attacks or harboring those who perpetrated the attacks. Although President Bush identified the terrorist group Al Qaeda and individuals within that group as the perpetrators of the attacks, and the Taliban then governing Afghanistan as the entity that harbored Al Qaeda, these actors were not specifically named in the 2001 AUMF's language. The 2001 AUMF represented a novel approach to modern-era military force authorizations, because it empowered the President to target non-state actors, even to the individual level, instead of only states. In contrast to the authorization enacted by Congress in the 2001 AUMF, the legislation originally proposed by the Bush Administration in the wake of the September 11, 2001, attacks would have provided the authority to use military force not only against Al Qaeda and the Taliban, but also to counter all terrorist threats generally, without necessitating a connection to the attacks: Resolved by the Senate and the House of Representatives of the United States of America in Congress assembled— That the President is authorized to use all necessary and appropriate force against those nations, organizations or persons he determines planned, authorized, harbored, committed, or aided in the planning or commission of the attacks against the United States that occurred on September 11, 2001, and to deter and pre-empt any future acts of terrorism or aggression against the United States . Because Congress did not accept this broader authorization language, it can be argued that Congress deliberately chose to limit presidential authority to respond to the threat posed by those who carried out and supported the September 11, 2001, attacks, and not to other persons, nations, or groups. The continuing application of 2001 AUMF authority and its perceived expansion has led to arguments over the proper scope of 2001 AUMF authority and calls for legislative clarification of such scope. Because Congress limited the use of force to targets associated with the September 11, 2001, attacks, while according broad discretion to the President regarding whom to target, implementing the 2001 AUMF has required the creation of frameworks and procedures to determine which uses of force fall under the 2001 AUMF's authority. Prior to the U.S. military campaign against the Islamic State that began in summer 2014, executive branch officials made statements that included certain interpretations concerning the 2001 AUMF: The 2001 AUMF is primarily an authorization to enter into and prosecute an armed conflict against Al Qaeda and the Taliban in Afghanistan. The 2001 AUMF authorizes the President to use military force against Al Qaeda and the Taliban outside Afghanistan, but such uses of force must meet a higher standard of threat to the United States and must use limited, precise methods against specific individual targets rather than general military action against enemy forces. Because the 2001 AUMF authorizes U.S. involvement in an international armed conflict, the international law of armed conflict informs the authority within the 2001 AUMF.