Mexican-American War

The whole states of California, Nevada, Utah and Texas, as well as parts of Wyoming, Colorado, Oklahoma, Arizona, New Mexico and Kansas.

At the end of the Mexican-American War (1846-1848) Mexico lost present-day California, Nevada, Utah, part of Colorado as well as most of northern New Mexico and Arizona. Also at the end of the war Mexico was forced to cease any attempt on reclaiming Texas, which at the time included present-day Texas, as well as those parts of Oklahoma, Kansas, Colorado and Wyoming described above. This is also known as the Mexican Cession (1848).

American presidents John Tyler (term 1841-1845) and James K. Polk (term 1845-1849) had a crush for California and looked to acquire it by any means necessary. The immediate consequences of such actions led to the Mexican Cession, where the United States acquired by force the states of California, Nevada, Utah, Texas and parts of Colorado, Arizona, New Mexico, and Wyoming. Ultimately, this led to the American Civil War(1861-1865).

Causes:

When Mexico won its independence from Spain in 1821, all the territories it possessed included Mexico, most of Central America (Belize, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama) as well as today's US States of California, Nevada, Utah, Texas and parts of Colorado, Arizona, New Mexico, and Wyoming.

Due to the extremely low population for such territorial extension (estimated at 12 million during 1824), Mexico relaxed its immigration policies, thus allowing American settlers to help populate the northern territories. The conditions to settle were simple: 1) to pledge allegiance to Mexico and 2) observe the Mexican Law and customs. In 1830, these laws incorporated the banning of slavery. Due to the fact that many American settlers in such territories were slave owners, they looked for any pretext to break up with Mexico.

Later, Mexican President Antonio Lopez de Santa Anna took measures to transform Mexico from a Federal Republic to a Centralist Republic. This move prompted Yucatan and Texas to secede from Mexico. Santa Anna's government invaded both republics; while Yucatan was regained, Texas was lost. As it happens to be the case between today's mainland China and Taiwan, Mexico looked Texas as a rebellious province to be reincorporated at a later time, preferably by diplomatic means, but by force if necessary. The Mexican government warned America that annexation would mean war.

Then, American President John Tyler found out about California and its riches. On a letter by American Plenipotentiary Minister in Mexico, Waddy Thompson, Jr.:

"As to Texas I regard it as of very little value compared with California, the richest, the most beautiful and the healthiest country in the world... with the acquisition of Upper California we should have the same ascendency on the Pacific... France and England both have had their eyes upon it."

He then desperately looked to fulfill the Manifest Destiny, a term which called for the annexation of all North America into the United States. He didn't believed in Texas but looked to annex all the territories west of the Louisiana, being California the "Jewel of the Crown". Long story short, he pushed for annexation of Texas, offering its admission to the Union in March 1, 1845. Then, President James K. Polk ratified by law such admission, on December 29 of that year. These events led to the war with Mexico.

Consequences:

Mexico lost the war due to poor strategic decisions and numeric and technological superiority by American forces: almost 79,000 American soldiers against an army of up to 40,000 Mexican regulars. The Treaty of Guadalupe Hidalgo (Tratado de Guadalupe Hidalgo in Spanish) is the peace treaty, largely dictated by the United States to the interim government of a militarily occupied Mexico, that ended the war. The cession that the Treaty facilitated included parts of the modern-day US states of Colorado, Arizona, New Mexico, and Wyoming, as well as the whole of California, Nevada, and Utah, and, depending on one's point of view, Texas.

As much of this conflict was instigated by Texas and its slave owners (when Texas seceded from Mexico, former American settlers regained their "right" to purchase and sell slaves), this meant an increase in slave territory. In 1849, General Zachary Taylor became President after keeping views on slavery in Texas secret during his campaign. He then revealed his plan to admit California and New Mexico as free states excluding creation of territories subject to slavery. Texas, supported by the other slave states, threatened military action to enforce its claim to New Mexico land, thus setting the stage for the American Civil War (1861-1865).

Mexico severed diplomatic ties to the United States after the U.S. annexed Texas, and started a low-intensity conflict along the US-Mexico border, which actually, was ill defined -- Americans believed the border to be the Rio Grande River, while Mexicans thought it was the Nueces River, several miles to the north.

This resulted in skirmishes between Mexicans and Americans, resulting in American blood spilled in this no man's land. This was used by president Polk as a casus belli to start the war. He however, was uninterested in Texas: he wanted to "acquire" California from Mexico at any cost.

General Porfirio Díaz (1830-1915) was a mestizo from Oaxaca. He opposed Santa Ana, fought for Juarez in the War of Reform, and with his brother fought against Emperor Maximilian. He was one of Juarez's more effective generals. He ran unsuccessfully against President Juarez (1871). He claimed electoral fraud and decided to use force and overthrow the government (1876). He introduced a dictatorship which ruled Mexico for nearly 40 years. is iron-fisted rule, which lasted almost 40 years which Mexicans refer to as the Porfiriato. He and his Cientificos ruled Mexico under the banner of "Liberty, Order, and Progress". Díaz had a very specific interpretation of these terms. Liberty was extended to supportive landowners, industrialists, and entrepreneurs to make money. Order was enforced through a policy of pan y palo (bread and club). Progress was rapid economic development. Díaz negotiated arrangements with foreiners in which he and his associates profited personally. Any opposition or even criticism was suppressed, often brutally. The Díaz dictatorship introduced a degree of modernization. Mexico in 1910 had a much more developed infrastructure than that of the country he had seized control of in 1876. It was, however, still an underdeveloped country. Díaz did not address Mexico's deep-seeded social problems. Ans a key area that he did not invest in was Mexico's human capital. Mexico was still a country with a small middle-class and a largely illiterate rural peasantry living in essentially feudal conditions. The Mexican Revolution was the first of the great 20th century peasant revolutions. When the Revolution came, it was a surprise to everyone--not the least to Mexicans. Díaz was astonished that the effete little teetotaling lawyer could succeed in overthrowing him. When departing for Mexico he warned, "Madero has unleashed a tiger, let us see if he can control him."

The above explanation explains why Dias was overthrown, but does not explain why the Mexican Revolution erupted into a major Revolution. Mexico was not only an underdeveloped country with a small middle-class, but it was a largely rural country with a largely landless peasantry, primarily of Native American ancestry. Most of Mexico's productive land was owned by a small number of wealthy hacendados operating huge, sprawling estates. When the peasantry joined the largely middle-class revolt that Madero launched, for better or worse, the Revolution began. Yes this is an important addition. I personally would add the absence of the rule of law, especially for the peasantry.

The above covers the causes of the Revolution, but a very important question that must be addressed in connection to the Revolution is if it promoted Mexico's development as a modern, productive country or created a political structure which made this development possible. And particularly did it establish the rule of law, a central component of a modern society. And an important part of this discussion is to what extent the modern situation where working-class Mexicans have to migrate to the United States to find decent paying jobs has its roots in the Revolution.

The United States bought California (and New Mexico) for $15 million from the Mexican government.

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