war powers

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War Powers refers to both Congress’ and the President’s Constitutional powers over military or armed conflicts by the United States. Article I, Section 8, Clause 11 of the U.S. Constitution grants Congress the power to declare war. The President, derives the power to direct the military after a Congressional declaration of war from Article II, Section 2. This presidential power is titled as Commander-in-Chief of the armed forces. These provisions require cooperation between the President and Congress regarding military affairs, with Congress funding or declaring the operation and the President directing it. 

Nevertheless, Presidents have engaged in military operations without express Congressional consent. These operations include the Korean War, the Vietnam War, Operation Desert Storm, the Afghanistan War of 2001 and the Iraq War of 2002. However, Congress never explicitly declared war during these operations; therefore, they are not considered official wars by the United States. 

Commander-in-Chief

Congress passed the War Powers Resolution of 1973 in response to the Kennedy, Johnson, and Nixon Administrations committing U.S. troops to Southeast Asia without Congressional approval. The War Powers Resolution requires that the President communicate to Congress the committal of troops within 48 hours. Further, the statute requires the President to remove all troops after 60 days if Congress has not granted an extension. After the September 11 Terrorist Attacks, the United States Congress passed the Authorization for Use of Military Force against Terrorists (AUMF). AUMF granted the President all necessary uses of force by nations or people associated with the 9/11 attacks. 

Emergency Powers

The Constitution does not expressly grant the President additional powers in times of national emergency. However, Presidents have claimed they do have emergency powers, often conflicting with the Supreme Court's interpretation of the extent of Presidential powers.

President Abraham Lincoln's suspended habeas corpus without Congressional approval during the Civil War. Lincoln claimed he could suspend habeas corpus due to emergency war powers and ignored the Federal District Court of Maryland stating only Congress had such power in Ex Parte Merryman.

President Franklin Delano Roosevelt similarly invoked emergency powers when he issued Order 9066, placing Japanese Americans into internment camps during World War II. The U.S. Supreme Court initially upheld this order in 1944 Korematsu v. United States. However, in 2018, the Court repudiated Korematsu in Trump v Hawaii, while simultaneously upholding an executive order travel ban.  

Harry Truman declared the use of emergency powers when he seized private steel mills that failed to produce steel because of a labor strike in 1952. With the Korean War ongoing, Truman asserted that he could not wage war successfully if the economy failed to provide him with the material resources necessary to keep the troops well-equipped. The U.S. Supreme Court, however, refused to accept his argument in Youngstown Sheet & Tube Co. v. Sawyer, holding that neither Commander-in-Chief powers nor any claimed emergency powers gave the President the authority to unilaterally seize private property without Congressional legislation.

See also: 

  • The War Powers Resolution
  • Authorization for Use of Military Force against Terrorists
  • The Detainee Treatment Act
  • Geneva Conventions and their additional protocols
  • Uniform Code of Military Justice

[Last updated in July of 2024 by the Wex Definitions Team