In the traumatic and somber aftermath of the September 11, 2001 terrorist attacks, the U.S. Congress passed a critical piece of legislation to provide the president authority to defend the United States and its interests abroad. The Authorization for Use of Military Force (AUMF), which responded to the horrors of 9/11, began the United States’ longest war—the global war on terror— and serves as its legal basis today. President George W. Bush signed the AUMF into law on September 18, 2001, only a week after the attacks. Congress agreed with the proposition:
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 Sept. 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 AUMF enabled President Bush to defend the United States against al-Qa’ida and other entities that carried out 9/11. Congress rejected the Bush administration’s first draft of the legislation because they believed it was too expansive. The initial wording provided the president with authority “to deter and pre-empt any future acts of terrorism or aggression,” which Congress rejected on the grounds that such language would provide the Executive Branch with power at the expense of Congress. Congress rejected other requests from the Bush administration, including one to transfer appropriations power to the president, and another that restricted Congress’ access to classified briefings. The Bush administration also asked for authority to waive restrictions on foreign assistance without notifying Congress, which could unilaterally override Congressional mandates not to assist countries who commit human rights violations, cause nuclear proliferation, and sponsor terrorism. As David Abramowitz, the Democratic Chief Counsel of the House Committee on International Relations, explained at the time, “the requests from the White House in response to this crisis were particularly breathtaking, and the results of many of these proposals were far narrower than those put forth initially by the President.” In other words, the rejection by a Congress of expanded executive authority guarded the separation of powers.
Collinger, Benjamin, "The Terror Exception: The Impact of the 2001 Authorization for Use of Military Force on United States Counterterrorism Policy in the Middle East Under the Obama Administration" (2016). Undergraduate Student Research Awards. 34.