Two days after terrorists attacked the World Trade Center and the Pentagon, a Harris poll conducted for Time/CNN reported that nearly two out of three Americans believed that the United States should "declare war." (1) A StrategyOne survey also conducted two days after the attacks found eighty-one percent of Americans in favor of such action, with only eight percent opposed. (2) That same day, nine members of Congress announced their support for a formal declaration of war. (3) The idea was quickly embraced in newspapers, (4) and even by Harvard Law School Professor Alan Dershowitz. (5)
In fact, as a constitutional matter, the President needed no approval from Congress to use lethal force in response to the terrorist attacks. Even the War Powers Resolution recognizes the independent constitutional power of the President to send U.S. forces into combat without legislative approval in response to an attack on the United States or its armed forces. (6) But as a political matter, getting Congress on record by statute in support of an effective response was very important.
Congress provided support for the President's response in the form of a joint resolution, providing in part:
[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. (7)
During the debate, concern was expressed about not giving the President a "blank check," (8) as Congress did in enacting the Gulf of Tonkin Resolution in August, 1964. (9) This argument undercut the cherished myth that Congress was not a full partner in committing the United States to war in Indochina and ignored the reality that "declarations of war" were by their nature "blank checks." To allay such concerns, language of the resolution seemed carefully designed to provide an "out" for legislators if the campaign went badly, as it would not be difficult to argue that any presidential action that later proved unpopular with voters was not "appropriate" and was thus unauthorized by Congress. In the end, however, even Senate Foreign Relations Committee Chairman Joseph Biden acknowledged that the resolution passed by Congress was "the constitutional equivalent of a declaration of war." (10)
As a matter of constitutional law, Senator Biden was exactly fight; a joint resolution authorizing the President to use military force fully satisfies any requirement for legislative approval under Article I, Section 8, Clause 11 of the Constitution. (11) But such statements betray a fundamental misconception of the relative roles of Congress and the President in the commitment and use of U.S. armed forces abroad and of the nature of war in the current international context. As a matter of international law, a formal declaration of war is an anachronistic irrelevancy. This misconception is the result of debates over the past three decades in which the historical understanding and development of war powers was neglected. Given the revived public interest in these issues, this is an opportune time to clarify the meaning of Congress's power to "declare war."
I. THE CONSTITUTIONAL ALLOCATION OF POWERS RELATED TO THE USE OF MILITARY FORCE
The debate over the constitutional separation of powers concerning the use of armed force abroad during the past three decades has been remarkably unimpressive. Few commentators have taken the time to look seriously at the historical aspect of the problem, and some act as if the 1972-73 War Powers Resolution debates were an issue of first impression.
Throughout most of our history, both Congress and the President understood that decisions regarding foreign affairs were different from domestic issues and were the province of the executive except in areas where the Constitution had made a clear exception. …