The terrorist attacks on the United States on September 11, 2001 raised important questions concerning the President's authority to take military action in response. Although Congress acted promptly to pass legislation authorizing the President to take military action against the terrorists and those linked to them, (1) we shall argue the President has broad constitutional power, even without such legislation, to deploy military force to retaliate against those implicated in the September 11 attacks. Congress acknowledged this inherent executive power in its recent legislation, as it had earlier in the War Powers Resolution (the "WPR"). (2) Further, we shall argue, the President had the innate power not only to retaliate against any person, organization, or state suspected of involvement in terrorist attacks on the United States, but also against foreign states suspected of harboring or supporting such organizations. Finally, we shall contend that the President's constitutional authority to deploy military force against terrorists and the states that harbor or support them includes both the power to respond to past attacks and the power to act preemptively against future ones.
Our analysis falls into four parts. First, we examine the constitutional text and structure. We conclude that the Constitution vests the President with the plenary authority, as Commander in Chief and the sole organ of the nation in its foreign relations, to use military force abroad, especially in response to grave national emergencies created by sudden, unforeseen attacks on the people and territory of the United States. Second, we confirm that conclusion by reviewing executive and judicial statements and decisions interpreting the President's constitutional powers. Third, we analyze the relevant historical precedent, which supports the argument for Presidential authority in these matters. Finally, we discuss congressional enactments that acknowledge the President's full authority to use force both to respond to the September 11 attacks on the United States and to deter future strikes of that nature.
The President's constitutional power to defend the United States and its citizens must be understood in the context of the Founders' express intention to create a federal government "clothed with all the powers requisite to [the] complete execution of its trust." (3) Foremost among the objectives committed to that trust is the the nation's security. (4) As Hamilton explained in arguing for the Constitution's adoption, because:
the circumstances which may affect the public safety are [not] reducible within certain determinate limits, ... it must be admitted, as a necessary consequence that there can be no limitation of that authority which is to provide for the defense and protection of the community in any matter essential to its efficacy. (5) "It is `obvious and unarguable' that no governmental interest is more compelling than the security of the Nation." (6) Within the limits that the Constitution itself imposes, the scope and distribution of the powers to protect national security must be construed to authorize the most efficacious defense of the nation and its interests in accordance "with the realistic purposes of the entire instrument." (7) Nor is the authority to protect national security limited to actions necessary for "victories in the field." (8) The authority over national security "carries with it the inherent power to guard against the immediate renewal of the conflict." (9)
The text, structure, and history of the Constitution establish that the Founders entrusted the President with the primary responsibility, and therefore the power, to use military force in situations of emergency. Article II, Section 2 states that the "President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States." (10) He is further vested with all of "the executive Power" and the duty to execute the laws. These powers give the President broad constitutional authority to use military force in response to threats to the national security and foreign policy of the United States. (11) During the period leading up to the Constitution's ratification, the executive was understood as having the power to initiate hostilities and control conflict escalation. (12)
By its terms, these provisions vest full control of the United States military forces in the President. The power of the President is at its zenith under the Constitution when directing military operations of the armed forces, because the power of Commander in Chief is assigned solely to the President, as the Court has confirmed. In The Prize Cases, for example, the Court explained that, whether the President "in fulfilling his duties as Commander in Chief" was justified in treating the southern States as belligerents and instituting a blockade, was a question "to be decided by him." (13) The Court could not question the merits of his decision, but must leave evaluation to "the political department of the Government to which this power was entrusted." (14) As the Court also observed, the President enjoys full discretion in determining what level of force to use. (15)
Some commentators have read the constitutional text differently. They argue that Congress has the sole authority to decide whether to make war. (16) This view, however, misinterprets the constitutional text and misunderstands the nature of a war declaration. Declaring war is not tantamount to making war; indeed, the Constitutional Convention specifically amended the working draft of the Constitution that had given Congress the power to "make" war. When it took up this clause on August 17, 1787, the Convention voted to change the clause from "make" to "declare." (17) A supporter of the change argued that the new language would "leav[e] to the Executive the power to repel sudden attacks." (18) In addition, other elements of the Constitution describe "engaging" in war. (19) This fact demonstrates that the Framers understood "making" and "engaging" in war to be somewhat broader than simply "declaring" war. A State constitution at the time of the ratification included provisions that prohibited the governor from "making" war without legislative approval. (20) If the Framers had wanted to require congressional consent before the initiation of military hostilities, they would have used such language.
Finally, the Framer's generation also understood that declarations of war were becoming obsolete. Not all forms of hostilities rose to the level of a "declared" war. During the seventeenth and eighteenth centuries, for example, Great Britain and colonial America waged numerous conflicts against other nations without an official declaration of war. (21) As Alexander Hamilton observed during the ratification, "the ceremony of a formal denunciation of war has of late fallen into disuse." (22) Instead of serving as an authorization to begin hostilities, a declaration of war was only necessary to "perfect" a conflict under international law. A declaration served to fully transform the international legal relationship between two states from one of peace to one of war. (23) Given this contextual understanding, Congress's power to "declare" war would not limit the President's independent and plenary constitutional authority over the use of military force.
Our reading of the text is reinforced by analysis of the constitutional structure. First, it is clear that the Constitution secures all federal executive power in the President to ensure a unity in purpose and energy in action. "Decision, activity, secrecy, and dispatch will generally characterize the proceedings of one man in a much more eminent degree than the proceedings of any greater number." (24) The centralization of authority in the President alone is particularly crucial in matters of national defense, war, and foreign policy, where a unitary executive can evaluate threats, consider policy choices, and mobilize military and diplomatic resources with a speed and energy that is far superior to any other branch. As Hamilton noted, "[e]nergy in the executive is a leading character in the definition of good government. It is essential to the protection of the community against foreign attacks." (25) This point applies to the war context as well. "Of all the cares or concerns of government, the direction of war most peculiarly demands those qualities which distinguish the exercise of power by a single hand." (26)
Second, the Constitution makes clear that the process used for conducting military hostilities is different from other government decision-making practices. In the area of domestic legislation, the Constitution creates a detailed, finely wrought procedure in which Congress plays the central role. In foreign affairs, however, the Constitution does not establish a mandatory, detailed, congressionally driven procedure for taking action. Rather, the Constitution vests the two branches with different powers--the President as Commander in Chief, and the Congress with control over funding and declaring war--without requiring that they follow a specific process in making war. By establishing this framework, the Framers expected that the process for war making would be more flexible, and capable of quicker, more decisive action, than the legislative process. Thus, the President may use his commander-in-chief and executive powers to use military force to protect the nation, subject to congressional appropriation and control over domestic legislation.
Third, the constitutional structure requires that any ambiguities in the allocation of a power that is executive in nature, such as the power to conduct military hostilities, must be resolved in favor of the executive branch. Article II, Section 1...