In November 1973 the US Congress passed the War Powers Act, which limited the president’s legal authority to deploy US troops for more than 60 days without either a declaration of war or congressional approval:
“Joint resolution concerning the war powers of Congress and the President.
Section 1
This joint resolution may be cited as the “War Powers Resolution”.
Section 2
a. It is the purpose of this joint resolution to fulfil the intent of the framers of the Constitution of the United States and ensure that the collective judgment of both the Congress and the President will apply to the introduction of United States Armed Forces into hostilities … and to the continued use of such forces in hostilities or in such situations.
b. Under Article I of the Constitution, it is specifically provided that the Congress shall have the power to make all laws necessary and proper for carrying into execution, not only its own powers but also all other powers vested by the Constitution in the Government of the United States, or in any department or officer thereof.
c. The constitutional powers of the President as Commander-in-Chief to introduce United States Armed Forces into hostilities, or into situations where imminent involvement in hostilities is clearly indicated by the circumstances, are exercised only pursuant to [either] a declaration of war, specific statutory authorisation, or a national emergency created by attack upon the United States … or its armed forces.
Section 3
The President in every possible instance shall consult with Congress before introducing United States Armed Forces into hostilities … and after every such introduction shall consult regularly with the Congress until United States Armed Forces are no longer engaged in hostilities or have been removed from such situations.
Section 4
In the absence of a declaration of war, in any case in which United States Armed Forces are introduced … the President shall submit within 48 hours to the Speaker of the House of Representatives and to the President pro tempore of the Senate a report in writing, setting forth:a. the circumstances necessitating the introduction of United States Armed Forces;
b. the constitutional and legislative authority under which such introduction took place; and
c. the estimated scope and duration of the hostilities or involvement.
The President shall provide such other information as the Congress may request in the fulfilment of its constitutional responsibilities with respect to committing the Nation to war and to the use of United States Armed Forces abroad.
Within sixty calendar days after a report is submitted or is required to be submitted … the President shall terminate any use of United States Armed Forces … unless the Congress has declared war or has enacted a specific authorisation for such use of United States Armed Forces; [or] has extended by law such 60-day period or is physically unable to meet as a result of an armed attack upon the United States…
Carl Albert
Speaker of the House of Representatives.
James O. Eastland
President of the Senate pro tempore.
November 7th 1973″