War With Mexico, 1846–1848

WAR WITH MEXICO, 1846-1848 The United States expansionist zeal drove them to war with Mexico in 1846. At the conclusion of the Texas War for Independence, Santa Anna was forced to concede that the Rio Grande marked the border between the United States and Mexico, as the United States had long maintained. Santa Anna made assurances, but Mexico argued the boundary was further north, at the Nueces River, and would not be constrained by them. Setting it at the Rio Grande would essentially give the US authority over territory it had never owned. Therefore, when President Polk ordered US troops into the disputed regions in 1846, Mexico saw it as a violation of its sovereign territory. It seemed to the Mexicans that the United States had invaded their country. A Mexican cavalry regiment was on patrol when the American army, which had been deployed to the banks of the Rio Grande to establish a fort on the "American" side, came upon it in January 1846. Sixteen American soldiers were injured or killed when gunfire broke out. President Polk ordered that Mexico be declared a war-making country, angrily stating that Mexico "has invaded our territory and shed American blood upon American soil." This Congress obliged on May 12. The tiny but vociferous antislavery group condemned the choice to enter the war, claiming that Polk had instigated hostilities on purpose in order for the US to seize additional slave territories. Representative Abraham Lincoln of Illinois and other Congressmen wanted to know the exact location on American territory where American blood had been spilled in the "Spot Resolutions." The war was also opposed by many Whigs. Nonetheless, Democrats backed Polk's choice, and a large number of volunteers for the army appeared from all throughout the nation, with the exception of New England, which was the center of abolitionist activity. The popular perception that Mexico was a poor, weak nation and that the Mexican people were simple to defeat since they were seen as illiterate, lethargic, and under the influence of a dishonest Roman Catholic church contributed to the enthusiasm for the conflict, Three primary goals characterized U.S. military strategy: 1) conquer northern Mexico, including New Mexico; 2) seize California; and 3) grab Mexico City. The first objective was given to General Zachary Taylor and his Army of the Center, who quickly took control of the Mexican city of Monterrey thanks to their superior weaponry. The American people saw Taylor as a hero very soon, and Polk named him commander of all U.S. forces. Colonel Sterling Price took over as commander when General Stephen Watts Kearny, the Army of the West leader, accepted Santa Fe, New Mexico's capitulation and proceeded to seize control of California. Kearny promised the people of New Mexico not to worry for their lives or their possessions, but in January 1847, the people rebelled and tried to push the Americans out. Tensions persisted even after Price put a stop to the uprising. As for Kearng, when he got in California it was already in American hands, thanks to the combined efforts of U.S. naval commander John D. Sloat, California residents, and John C. Fremont, son-in-law of Missouri senator Thomas Benton and former army captain, When Sloat heard that the war had broken out, he swiftly made sail for California while at anchor off the coast of Mazatlan. Less than a month after a party of American immigrants led by William B. Ide had gained control of Sonoma and declared California a republic, he captured the town of Monterey in July 1846. San Francisco fell to the navy without a fight, one week after Monterey. While a small group of Californians attempted a brief uprising in September 1846, the majority of them acquiesced to the American occupation. Kearny's only real task as governor of California was to assume control of the state. General Winfield Scott led the Army of the South. Both Scott and Taylor were viable presidential candidates, and Polk assigned Scott the campaign to prevent elevating the more well-liked Taylor, who was dubbed "Old Rough and Ready." Scott captured Veracruz in March 1847, and from there, he moved northwesterly (much like Spanish conquistador Hernán Cortés had done in 1519), slowly closing in on the capital. Polk believed, correctly, that whoever seized Mexico City would become a hero. But every step along the way was a laborious win, as Mexican soldiers and citizens heroically battled to drive out the American invaders and save their homeland. The young military cadets that defended Mexico City battled valiantly to the very end. Legend has it that Juan Escutia, a cadet, threw himself from the city walls with the Mexican flag wrapped around his body as a last gesture of bravery, Scott arrived in Mexico City's central square on September 14, 1847, the city had collapsed. The Mexican government and the United States negotiated for peace in 1848, leading to the Treaty of Guadalupe Hidalgo, despite Polk and other expansionists calling for "all Mexico." With the signing of the Treaty of Guadalupe Hidalgo in February 1848, Mexico gave over about half of its territory to the United States, marking a victory for American expansion. The acquisition of territory west of the Rio Grande was known as was known as the "Mexican Cession," and it comprised parts of Colorado and Wyoming as well as the present states of California, New Mexico, Arizona, Nevada, and Utah. The Rio Grande was acknowledged by Mexico as the US boundary as well. The United States pledged to respect the Spanish land concessions to the Pueblos in New Mexico and to offer citizenship to Mexican nationals residing in the surrendered area when those regions became states. In return, the United States compensated Mexico $15 million for the loss of its territory, agreed to take over $3.35 million in Mexican obligations owing to American citizens, and pledged to protect the people living in the Mexican Cession against Native American incursions. Despite the extent of the Mexican Cession, others contended that the US should not rest until it had conquered all of Mexico. Southerners rejected this notion in significant numbers because they did not want to incorporate Mexico's sizable mestizo population-people of mixed Native American and European ancestry-into the United States, even though they wanted to annex additional land for slaves. Some were opposed to absorbing a sizable portion of Roman Catholics. The concept of additional American territory home to mixed-race, Catholic inhabitants was unacceptable to these expansionists.