War With Mexico

Welcome to the Hidden History of Texas. This is Episode 44 – War With Mexico -  As always, brought to you by Ashby Navis and Tennyson Media Publishers, producers of  high quality games, productivity, mental health apps, and  a comprehensive catalog of  audiobooks. Visit AshbyNavis.com for more information.

The 1846-1848 conflict known in the United States as the Mexican-American War was called the U.S. Invasion by Mexico. It was fueled by the expansionist views of President James Polk and was an example of his belief in the ‘Manifest Destiny’. He firmly believed that the United States was destined by God to own all the land from the Atlantic to the Pacific.

After he became President and oversaw the annexation of Texas into the union as a State, he realized that since Mexico controlled everything west of Texas, it  was standing in his way. Initially he  tried to have Mexico agree to several small issues. After the Battle of San Jacinto, even though Texas and the United States claimed Texas was independent the fact was that Mexico had never officially signed a peace treaty. Polk wanted Mexico to recognize that the boundary between the United States and Mexico was the Rio Grande. He also wanted Mexico to sell Northern California to the United States. He did his best to pressure Mexico into accepting these terms, but he failed because nobody in Mexico would agree to giving up any territory to the United States and that especially included Texas.

Polk was not a person to take no for an answer, and he grew increasingly frustrated by Mexico. On January 13, 1846, he ordered the army that was under the control of Gen. Zachary Taylor's, which was in Corpus Christi, to move to the Rio Grande. Needless to say, the Mexican government took this to be an act of war. The Mexicans responded by crossing the Rio Grande on April 25 at Matamoros and  ambushed an American patrol.

Much like President Johnson would do later with the Gulf of Tonkin incident to justify further involvement in Vietnam, on May 13th, Polk used this to convince Congress to declare war on Mexico. He claimed that this was because "American blood had been shed upon American soil."  On May 8 and 9, even before the official declaration of war Taylor's army defeated a force of 3,700 Mexican soldiers under Gen. Mariano Arista in the Battles of Palo Alto and Resaca de la Palma

Initially the American forces tried to use the time-honored plan of blockading Mexican coastal cities and also occupying the Mexican states that bordered Texas. These plans were based on a very unrealistic belief that this would somehow coerce Mexico into giving up territory. In September General Taylor, accompanied by a significant number of volunteers that included many Texans, seized Monterrey. He then declared that General Arista had agreed to an armistice. Taylor succeeded in large part due to the role that  Col. John Coffee Hays's Texas Mounted Rifles played during the attack on the city.

 Polk, however, was not satisfied with the armistice and he denounced it, forcing Taylor to drive further south to Saltillo and then east to Victoria. Meanwhile Gen. John E. Wool lead more troops from San Antonio with the initial intention of threatening Chihuahua, instead he turned and ended up joining Taylor’s forces. Not content with just Texas and Mexico, President Polk sent Gen. Stephen W. Kearny from Fort Leavenworth with instructions to seize New Mexico.

Finally in July, as Taylor's forces were gathering, the navy sent its Pacificsquadron under Commodore John D. Sloat to occupy Monterey and San  Francisco, California. From that post they joined a force of Anglo settlers who  at the urging of the explorer John C. Frémont had established their own government. Although an August incursion into southern California failed, the area was eventually secured by a joint army-navy expedition under Kearny and Commodore Robert F. Stockton in January 1847.

Meanwhile,