3. Spanish-American War (1898)
On April 25, 1898, the United States declared war on Spain, following the explosion of the USS Maine in Havana Harbor and Spain’s refusal to grant Cuban independence. The conflict resulted in a swift U.S. victory, leading to Spain’s cession of Puerto Rico, Guam, and the Philippines. For the official declaration document, refer to the Senate’s records: (senate.gov).
