The President's Constitutional Authority to Conduct Military Operations Against Terrorist Organizations and the Nations that Harbor or Support Them

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, we argue that 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. Further, the President has the inherent 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 argue 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.