Skip to main content

Article I – War Powers

Article I, Section 8, gives Congress the power to declare war.

1787Framers Give Congress The Power To Declare War In Article I

The framers specified the powers of Congress in great detail in Article I, Section 8, of the Constitution. They include the power to declare war.

1801U.S. Takes Military Action Without A Declaration of War

When the United States refuses to pay tribute to the North African Barbary pirates, who have been raiding its ships in the Mediterranean, the pasha of Tripoli declares war on the United States. President Thomas Jefferson exerts his powers as commander in chief to set a naval blockade of Tripoli that results in a peace treaty in 1805.

1812Congress Enacts First Declaration of War

Britain’s interference with American shipping and a blockade of U.S. ports leads President James Madison to ask Congress for a declaration of war against Great Britain. The House votes 79 to 49 for war on June 4. The Senate votes more narrowly for war, 19 to 13, on June 18. In August 1814, British troops invade Washington, D.C., and burn the White House and Capitol, but are eventually turned back at Baltimore. The inconclusive war is ended by the Treaty of Ghent, but, before word of the treaty reached the United States, Americans score a morale-building victory at the Battle of New Orleans in January 1815.

1846War With Mexico Adds Vast Territories

A border clash between the United States and Mexico over disputed territory between the Rio Grande and Nueces Rivers, leaves eleven Americans dead. President James K. Polk asks Congress for a declaration of war. The House votes 174 to 14 for war on May 11, and the Senate adopts a war resolution the next day by a vote of 40 to 2. American troops capture the Mexican capital of Mexico City. By the Treaty of Guadalupe Hidalgo, Mexico, cedes its northernmost territory to the United States, lands that today include the states of California, Arizona, Utah,Nevada,New Mexico, Colorado, and Wyoming.

1861North Views Secession as an Insurrection

Soon after the election of President Abraham Lincoln, eleven southern states secede from the Union and form the Confederacy. When Lincoln declines to surrender Fort Sumter in the harbor of Charleston, South Carolina, Confederate forces fire upon and capture the fort. Lincoln then declares that an insurrection exists and calls on Northerners to volunteer for military service. Lincoln calls Congress into emergency session on July 4 but does not seek a formal declaration of war. After four brutal years of fighting, the South surrenders in April 1865.

1898Spanish-American War Ends Swiftly

The American public is outraged over reports of Spanish atrocities in Cuba, and the explosion and sinking of the USS Maine in Havana Harbor. President William McKinley responds to sentiments in Congress with a war message on April 11. On April 25, the House and Senate declare war by voice votes. The brief conflict sees American victories against the Spanish in Cuba and the Philippines.

1917United States Drawn Into European War

In 1914 the Triple Entente of Great Britain, France, and Russia goes to war against the Triple Alliance of Germany, Austria-Hungary, and Italy. The United States stays neutral until German attacks on American shipping convince President Woodrow Wilson to ask Congress, in 1917, for a declaration of war. The Senate passes the war resolution by a vote of 82 to 6 on April 4, and the House by a vote of 373 to 50 on April 6. Entry of U.S. forces into the conflict tips the balance against Germany, which accepts an armistice in November 1918. The Senate twice defeats the Treaty of Versailles. But, the Senate finally approves a treaty with Germany that formally ends the war in 1921.

1941Congress Enacts Last Official Declaration of War

On December 7, 1941, a Japanese surprise attack destroys the U.S. fleet at Pearl Harbor, Hawaii, which is a U.S. territory. President Franklin Roosevelt calls for a declaration of war against Japan, which Congress adopts with only one dissenting vote in the House. Japan’s allies, Germany and Italy, also declare war on the United States, and Congress unanimously declares war against them. In June 1942, Congress again unanimously declares war on three of Germany’s allies, Bulgaria, Hungary, and Romania. Italy is defeated in 1943, and Germany surrenders in May 1945. Following the use of atomic weapons against Hiroshima and Nagasaki, Japan announces its surrender in August 1945, signing the Japanese Instrument of Surrender on September 2. World War II marks the last time that the U.S. Congress officially declares war against another nation.

1950United States Engages In A Police Action In Korea, Bypassing Congress

North Korean troops invade South Korea in 1950. President Harry S.Truman does not ask Congress for a declaration of war in support of South Korea but instead dispatches U.S. troops to support the United Nations’ effort in Korea, which he calls a police action. An armistice reached in 1953 leaves Korea divided.

1964Gulf of Tonkin Resolution Used as War Declaration

After President Lyndon Johnson reports that North Vietnamese patrol boats have fired on American naval vessels in the Gulf of Tonkin, Congress passes the Gulf of Tonkin Resolution. It authorizes the President to take all necessary measures to repel another armed attack and to prevent further aggression. President Johnson later uses the Gulf of Tonkin Resolution as a declaration of war enabling him to commit several hundred thousand American troops to South Vietnam. The United States withdraws its troops from South Vietnam in 1973, after signing a peace treaty. Hostilities between the North and South continue until Congress finally cuts off all military aid to the South in 1975. North Vietnam prevails and unites Vietnam under its rule.

1973Congress Reasserts Its Authority With War Powers Resolution

Congressional frustration with the prolonged war in Vietnam leads to passage of the War Powers Resolution on Nov. 7, 1973, over President Richard Nixon’s veto. The resolution requires presidents to notify Congress within 48 hours of committing U.S. combat troops abroad, and establishes a 60-day limit on the deployment of troops in combat overseas without congressional approval. The resolution remains controversial, with varying arguments over its effect on the power of Congress, as well as that of the president.

1991United States Goes To War In The Persian Gulf By UN Resolution

After Iraq invades Kuwait and threatens Saudi Arabia, President George H.W. Bush organizes a multinational coalition and persuades the United Nations to impose sanctions on Iraq and set a deadline for Iraq’s withdrawal. Congress passes a resolution authorizing the use of force in support of the United Nations. On January 16, 1991, American-led coalition forces attack Iraqi positions. The war ends in one hundred hours, with Kuwait freed from Iraqi occupation.

2001United States Responds to Terrorism

The United States responds to terrorist attacks in New York City and Washington, D.C., on September 11, 2001, by attacking Afghanistan, which had hosted the terrorist organization responsible for the attacks. President George W. Bush then asserts the nation’s right to fight preemptive wars. He identifies Iraq as having links to terrorists and warns that it possesses weapons of mass destruction.

Related Resources