#12: The Gulf of Tonkin Resolution (1964)
In August 1964, following disputed reports of attacks on U.S. naval ships in the Gulf of Tonkin, Congress acted swiftly. They passed the Gulf of Tonkin Resolution, which gave President Lyndon B. Johnson sweeping authority to use military force in Southeast Asia. It was not a formal declaration of war, but it functioned as one. The resolution gave the White House a blank check to escalate the conflict without further congressional approval. This act became the primary legal justification for sending American troops to Vietnam, turning a regional conflict into a major American war.
