HISTORY'S CURRENTS
DIPLOMATIC FAILURES AND THE MEXICAN WAR

The Mexican War began in 1846 soon after the Mexican government failed to accept an American offer to purchase the New Mexico and California territories. The offer was made by President James K. Polk, a Democratic president elected in 1844 on a platform of Manifest Destiny which included the annexation of Texas to the United States (with the Rio Grande as its southern boundary) and the settlement of the Oregon question with Great Britain. Texas was annexed shortly after the election (with no agreement on the southern boundary), and the Oregon question was settled by treaty in the summer of 1845. With the Oregon question out of the way, the Polk administration went on to the Texas boundary question.

In August 1845, Polk sent John Slidell, a Louisiana member of the US House of Representatives (and later a Senator), to Mexico as a commissioner. Slidell had instructions to settle the Texas-Mexico boundary dispute (with the Rio Grande as the boundary) and purchase New Mexico and California for $40 million. The mission failed when the Mexican government felt insulted and refused to sell its northern territories or even accept Slidell’s credentials.

However, even before Slidell and the US were dishonored by the Mexican government’s actions, President Polk had positioned American forces under General Zachary Taylor near the disputed territory between the Nueces River and the Rio Grande. In January 1846, President Polk ordered General Taylor into the disputed territory and provoked a series of hostilities between American and Mexican forces in the area. Polk asked for a declaration of war claming “American blood had been shed on American soil” by the Mexicans. On May 11, 1846, Congress voted that a state of war existed between the United States and Mexico.

The Mexican War went well for the US forces. Taylor hammered his way into northern Mexico winning at Palo Alto, Resaca de la Palma, and Monterrey. California was seized through the efforts of Col. Stephen Kearney, army explorer John C. Freemont, known as the ‘pathfinder,” and naval forces under Commodores John Sloat. A third front was opened east of Mexico City by joint army-navy forces led by General Windfield Scott. Scott landed and took the Mexican port of Vera Cruz. From there the forces under Scott headed inland. The war should have been over soon, but diplomatic maneuvers to end the war swiftly served to drag out the fighting for another year.

At the start of hostilities, American agents contacted General Santa Anna (of remember the Alamo infamy), the deposed dictator of Mexico, living in Cuba. The exiled leader promised to sign a favorable treaty with the United States for passage through the American naval blockade of Mexico. Once he returned to Mexico, however, Santa Anna reneged on his promise and began to direct a much more formidable defense against American forces in Mexico. Forces under his command slowed the American advance on Mexico City and cost many needless American and Mexican causalities.

The final diplomatic fiasco was the Nicolas Trist mission during the war. Trist was an American diplomat for President Polk and was attached to the army commanded by General Scott. After the successful battles of Contreras, Churubusco, and San Antonio, General Scott might have moved promptly into the capital. Instead he allowed Trist to grant the armistice of Tacubaya on August 24 to negotiate a peace treaty. Santa Anna used the time to muster and redeploy his forces for a final defense of the city. Fighting was renewed on September 7,1846 at Molino del Rey, where the Americans forced the Mexican position but lost nearly 800 soldiers. The bloody battles of Chapultepec, Casa Mata and Mexico City ensued. While American forces finally took the city on September 12, the war was prolonged and even bloodier due to the botched truce with Santa Anna.

Trist redeemed himself with the Treaty of Guadalupe Hidalgo signed on Feb. 2, 1848. It confirmed U.S. claims to Texas and set the US-Mexican boundary at the Rio Grande. Mexico also ceded today’s states of California, New Mexico, Nevada, Utah, Arizona, Colorado, and Wyoming to the United States in exchange for $15 million and assumption by the United States of claims against Mexico by U.S. citizens. The treaty was ratified by the US Senate on Mar. 10, 1848, and by the Mexican Congress on May 25.

History’s currents or current history? You decide!