Document Type

Chapter of Book

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use of force, war powers resolution, syria, comparative constitutional law, presidential power


There is no issue of foreign relations law more important than the allocation of authority over the use of military force. This issue is especially important for the United States given the frequency with which it is involved in military activities abroad. Yet there is significant uncertainty and debate in the United States over this issue — in particular, over whether and to what extent military actions must be authorized by Congress. Because U.S. courts in the modern era have generally declined to review the legality of military actions, disputes over this issue have had to be resolved, as a practical matter, through the political process. For those who believe that it is important to have legislative involvement in decisions to use force, the political process has not proven to be satisfactory: presidents have often used military force without obtaining congressional approval, and Congress generally has done little to resist such presidential unilateralism. The United States is not the only country to struggle with regulating the domestic authority to use military force. This issue of foreign relations law is common to constitutional democracies, and nations vary substantially in how they have addressed the issue. Whether and to what extent such comparative materials should inform the interpretation or revision of U.S. law presents a complicated set of questions that are affected in part by one’s legal methodology and also by how the comparative materials are being invoked. This Chapter begins by describing the exercise of war powers authority in the United States, both before and after World War II, as well as some of the limitations on congressional and judicial checks on presidential uses of military force. It then considers the potential value of studying the war powers law and practice of other countries, as well some of the reasons to be cautious about relying on such comparative materials.

Library of Congress Subject Headings

War and emergency powers, Executive power, Legislative power, Comparative law