Glossary

War Powers Resolution

A 1973 law limiting the president's ability to commit U.S. forces to hostilities without congressional approval.

Also called: War Powers Act, 1973 War Powers Resolution

The War Powers Resolution of 1973 is a federal law meant to ensure Congress and the president share responsibility for decisions to use military force. The Constitution gives Congress the power to declare war and the president the role of commander in chief, and the resolution was passed over President Nixon's veto, by a veto override, after the Vietnam War.

It requires the president to consult Congress before introducing U.S. forces into hostilities "wherever possible," to report to Congress within 48 hours of doing so, and to end the use of forces within 60 days (with a possible 30-day extension for withdrawal) unless Congress authorizes it or declares war. Congress can also direct removal of the forces by concurrent resolution, a mechanism that is likely unconstitutional after INS v. Chadha (1983).

Presidents of both parties have said the law infringes on their constitutional powers and have taken military actions without authorization, often justifying them under earlier authorizations or as limited operations that fall short of "hostilities." Congress has rarely forced the issue; joint resolutions to end actions in Yemen, Libya and elsewhere have been vetoed or failed. Debates continue over how well the law works. See also Authorization for Use of Military Force.

Last reviewed November 8, 2026

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Related terms

Authorization for Use of Military Force A law in which Congress authorizes the president to use military force, such as the 2001 and 2002 authorizations. Separation of powers The constitutional division of government into legislative, executive and judicial branches, each with its own distinct powers. Checks and balances The constitutional design giving each branch of government ways to limit the others, so that no branch dominates. Veto override Congress's power to enact a bill over a presidential veto by a two-thirds vote in each chamber.