Causes of the War

From WolfWikis

A Background to the War

With Mexico’s independence from Spain in 1821, its outlook seemed positive with limitless possibilities. Mexico’s frontiers were still underpopulated and had many riches to be discovered. Following the Louisiana Purchase of 1803, many powerful men in the United States believed it was their duty and destiny to spread the country to the Pacific Ocean, a termed coined as manifest destiny.^[1]

The Mexican territory lay as a roadblock to be conquered, eventually leading up to the War for Texas Independence. Texas had been part of Mexico, but there had been an influx of Anglos moving into the region.

an oath of allegiance to Mexico; and second, to convert to Catholicism. It was difficult to enforce these provisions because of Texas’ large land expanse. By 1836, there was a strong movement for Texas independence. After several bloody battles between the Mexican army and Texas Freedom Fighters, the Texans won their independence. The Treaty of Velasco was signed, the fighting stopped, and Mexican leader Santa Anna and his army returned home.^[1]

However, hostilities rose again from a dispute over the southern boundary between Texas and Mexico. According to the Treaty of Velasco, the border was to run along the Rio Grande River. Mexico, however, claimed they had agreed the southern border would be the Nueces River. Actually, this dispute was only a smoke screen by the U.S. for the ensuing Mexican-American War.^[2]

annexation of Texas. In actuality, Polk wanted California and New Mexico as well, and was willing to do whatever necessary to get the territory. Mexico warned the U.S. if they annexed Texas, it would be a declaration of war. In December of 1945, the U.S. officially annexed Texas. Shortly after the annexation, John Slidell returned to Washington having failed in his attempt to purchase Texas, New Mexico and California from Mexico. Because of this failure,

to the Rio Grande; the second sent Colonel Stephen Kearney to the New Mexico territory; and the third directed the U.S. navy to reestablish a blockade of Mexican ports in the Gulf of Mexico. Polk had two goals in doing this; the first was to impose the American believed border along the Rio Grande. The second was to influence the people of those regions to pressure the Mexican government to sell the territories to the U.S.^[3] If this could not be achieved peacefully, Polk had troops in place to militarily take the territory from Mexico. After an American offer to purchase the California and New Mexico Territories, tensions between the US and Mexico rose further in 1846, over a border dispute. Since its independence, Texas claimed the Rio Grande as its southern border, while Mexico claimed the Nueces River farther to the north. As the situation worsened, both sides sent troops to the area.On the evening of April 25, 1846, while leading 70 US Dragoons to investigate a hacienda in the disputed territory between the rivers, Captain Seth Thornton stumbled upon a force of 2,000 Mexican soldiers. A fierce firefight ensued and 16 of Thornton’s men were killed before the remainder was forced to surrender.This would be known as the "Thornton Affair".^[4] Upon learning of the incident, President Polk asked for a declaration of war before the United States Congress, summing up the need for war by famously stating:"American blood has been shed on American soil". ^[5]

Manifest Destiny

One major cause of the war was the American's idea of "Manifest Destiny". Ever since President Jefferson's acquisition of the Louisiana Territory in 1803, Americans migrated westward in ever increasing numbers, often into lands not belonging to the United States. By the time President Polk came to office in 1845, an idea called "Manifest Destiny" had been stirring in the minds of the American people, and Polk was a firm believer in the idea of expansion. The belief that the U.S. basically had a God-given right to occupy and "civilize" the whole continent gained favor as more and more Americans settled the western lands.^[6] The fact that most of those areas already had people living upon them was usually ignored, with the attitude that the English-speaking America, with its high ideals and Protestant Christian ethics, would do a better job of running things than the Native Americans or Spanish-speaking Catholic Mexicans. In both 1835 and 1845, the United States offered to purchase California from Mexico, for $5 million and $25 million, respectively. The Mexican government refused the opportunity to sell half of its country to Mexico's most dangerous neighbor. ^[7]

Suggested Videos

US-Mexican War

References

Annotated Bibliography

Donald S. Frazier, “Boundary Disputes”, PBS.org, http://www.pbs.org/kera/usmexicanwar/prelude/md_boundary_disputes.html, accessed Oct. 5, 2007

Hon. Thomas J. Mackey, “Reunion of Veterans of the Mexican War in Washington City,” Dec. 6, 7, 8, 1883. http://militaryhistory.about.com/gi/dynamic/offsite.htm?zi=1/XJ&sdn=militaryhistory&cdn=education&tm=27&f=00&tt=11&bt=1&bts=0&zu=http%3A//www.aztecclub.com/. Accessed Oct.6, 2007

James K. Polk, “MESSAGE OF PRESIDENT JAMES K. POLK,” May 11, 1846. http://militaryhistory.about.com/gi/dynamic/offsite.htm?zi=1/XJ&sdn=militaryhistory&cdn=education&tm=27&f=00&tt=11&bt=1&bts=0&zu=http%3A//www.aztecclub.com/, accessed Oct. 6, 2007

Jesús Velasco-Márquez, “A Mexican Viewpoint on the War With the United States,” PBS.org, http://www.pbs.org/kera/usmexicanwar/prelude/md_a_mexican_viewpoint.html, accessed Oct. 4, 2007

John L. O'Sullivan, "Manifest Destiny," 1839, http://www.mtholyoke.edu/acad/intrel/osulliva.htm, accessed on Oct. 6, 2007

Miguel Soto, “The Divisions in Mexico during the War with the United States”, PBS.org, http://www.pbs.org/kera/usmexicanwar/prelude/dm_divisions.html. accessed Oct. 4, 2007

Thomas Hietala, “Expansionism and Imperialism”, PBS.org, http://www.pbs.org/kera/usmexicanwar/prelude/md_expansionism.html, accessed Oct. 7, 2007 link title