Also known as: declarations of war · declare war · declares war · declared war · declaring war · war declaration
Written by attorneys · grounded in primary & secondary sources — see below
A formal pronouncement by Congress that places the United States in a state of war with another nation. The pronouncement activates specific constitutional authorities to raise armies, regulate captures, and govern military forces during hostilities.
Daphne Doyle owns a merchant vessel carrying cargo from a foreign port. After Congress issues a declaration of war, federal authorities seize the vessel and its cargo as enemy property. The declaration supplies the legal basis for treating the shipment as subject to capture under congressional war powers.
Diego Duarte purchases pine timber from an American seller after the declaration of war against a foreign nation. The buyer attempts to claim the timber as his own property. The declaration renders the transaction void because commercial dealings with the enemy become unlawful once war is formally declared.
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Delilah Duran addresses a rally urging listeners to resist military conscription during an ongoing declared war. Prosecutors charge her with advocating unlawful conduct. The declaration of war supplies the national emergency context that courts weigh when determining whether the speech creates a clear and present danger of lawless action.
Darius Dixon, captured abroad while fighting for an enemy nation, challenges his indefinite detention by U.S. forces. A declaration of war has been issued by Congress. The declaration confirms the existence of active hostilities that support continued detention without criminal charges for the duration of the conflict.
Destiny Davis, a foreign national captured while aiding enemy forces, faces trial before a military commission. Congress has issued a declaration of war. The declaration establishes the armed conflict necessary for the commission to exercise jurisdiction over violations of the law of war.
Diane Dawson and several associates land on U.S. shores to conduct sabotage operations on behalf of a nation against which Congress has declared war. They are apprehended before completing any acts. The declaration of war authorizes their trial by military commission as unlawful belligerents rather than ordinary criminals.
No. Congress may authorize the President to federalize Guard units for overseas training even in the absence of a declared war or national emergency. Once federalized under a valid statute, the units operate under federal command and the governor of the home state loses any constitutional veto over the deployment.
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Yes. A declaration of war is not required for Congress to address lingering economic disruptions caused by prior hostilities. Regulations that bear a reasonable relationship to remedying wartime supply shortages or base realignments remain valid even after active combat ends.
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A declaration of war suspends ordinary commercial relations and renders subsequent contracts with enemy nationals unenforceable. Courts treat property involved in such transactions as subject to seizure or invalidation under the war powers granted by the declaration.
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…the influence which their constituents possess at elections, are, in this, as in many other instances, as that, for example, of declaring war, the sole restraints on which they have relied, to secure them from its abuse. They are the restraints on which the people must often rely solely, in all representative governments. The…