President James K. Polk declared war on Mexico in 1846, driven by the ideology of Manifest Destiny and territorial disputes. The Mexican-American War that followed resulted in significant territorial gains for the United States, including California and New Mexico. This war was a pivotal moment in U.S. history, reflecting the nation's expansionist goals. ;
President James K. Polk declared war on Mexico in 1846, leading to the Mexican-American War. This conflict was driven by territorial disputes and the idea of Manifest Destiny. The war resulted in significant territorial gains for the United States after the Treaty of Guadalupe Hidalgo in 1848.
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