Episode 117

The Mexican-American War – Annexation of Texas & Battle of Palo Alto

To understand the Mexican War, we have to start out with some politics and learn why Mexico was upset about losing Texas to the United States, and we'll learn that the dispute really focused on one thing...land.


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Before the war, a little bit of setup…

In order to understand why the United States would go to war with Mexico, we need to brush up on our history of Texas & Mexico. As we’ve talked about events on the podcast, we’ve not really ventured this far west yet, but as early as 1837, the United States recognized the Republic of Texas as an independent country.

But independent from whom? The US? Nope. From Mexico. You see Texas was originally part of the territory of Mexico, that Mexico referred to as a provinice of Tejas. If you grew up in the US, your history book may have referred to it as Mexican Texas, so if you’re familar with that term it’s the same thing.

There was a revolution that took place in 1836, between Mexico and this province of Tejas, which resulted in an independent country, known as the Republic of Texas, or Republica de Tejas in Spanish. This Texas war of independence ended on April 21, 1836, but Mexico refused to recognize the independence of the Republic of Texas, and intermittent conflicts between the two states continued into the 1840s. The United States recognized the Republic of Texas in March 1837 but declined to annex the territory.

Annex – that’s a word we’re going to hear alot this episode. Webster’s definition is as follows: to incorporate (a country or other territory) within the domain of a state The U.S. annexed Texas in 1845 – That’s right, the example of webster.com is part of the events we’re going to talk about today. But I do want to let all of my Texas history fans know – there’s ALOT of the history of Texas that I’m not going to cover, just because it’s outside the scope of this podcast. Texas’s history – mostly as a Spanish province of Mexico – dates back to the late 1600s, early 1700s. I’d encourage my listeners to go brush up on it as it’s quite fascinating.

Now what you do need to know is what Texas said was it’s territory. Most of the populated state during this time is what we would consider to be modern day eastern Texas. However the claim was that it was all of what we known as modern day Texas, as well as spilling over into modern day New Mexico, Colorado, a little bit of Kansas and Oklahoma.

So the next bit, get’s a little political – so I’ll do my best to just give you the highlights: The people of Texas, at least the majority of them, welcomed annexation by the United States – they wanted to be a part of it. It’s just that getting there took some time… President Andrew Jackson delayed recognizing the new republic until the last day of his presidency to avoid raising the issue during the 1836 general election. Jackson’s political caution was informed by northern concerns that Texas could potentially form several new slave states and undermine the North-South balance in Congress.

Jackson’s successor, President Martin Van Buren, viewed Texas annexation as an immense political liability that would empower the anti-slavery northern Whig opposition – especially if annexation provoked a war with Mexico. Presented with a formal annexation proposal from Texas minister Memucan Hunt, Jr. in August 1837, Van Buren summarily rejected it. Annexation resolutions presented separately in each house of Congress were either soundly defeated or tabled through filibuster. After the election of 1838, new Texas president Mirabeau B. Lamar withdrew his republic’s offer of annexation due to these failures. Texans were at an annexation impasse when John Tyler entered the White House in 1841.

William Henry Harrison, Whig Party presidential nominee, defeated US President Martin Van Buren in the 1840 general election. Upon Harrison’s death shortly after his inauguration, Vice-President John Tyler assumed the presidency. In his first address to Congress in special session on June 1, 1841, Tyler set the stage for Texas annexation by announcing his intention to pursue an expansionist agenda so as to preserve the balance between state and national authority and to protect American institutions, including slavery, so as to avoid sectional conflict. Tyler’s closest advisors counseled him that obtaining Texas would assure him a second term in the White House, and it became a deeply personal obsession for the president, who viewed the acquisition of Texas as the “primary objective of his administration”. Tyler delayed direct action on Texas to work closely with his Secretary of State Daniel Webster on other pressing diplomatic initiatives.

Now astute listeners will note that Tyler’s address sounds alot like Manifest Destiny, which was a 19th-century belief that the “expansion of the US throughout the American continents was both justified and inevitable.” and to be honest, yes, Manifest Destiny most likely influenced alot of the decisions around the annexiation of Texas and the subsequent war with Mexico.

By 1843 Tyler was ready to make a Texas annexation his top priority. However, by the summer of 1843 Sam Houston’s Texas administration had returned to negotiations with the Mexican government to consider a rapprochement that would permit Texas self-governance, possibly as a state of Mexico, with Great Britain acting as mediator. Texas officials felt compelled by the fact that the Tyler administration appeared unequipped to mount an effective campaign for Texas annexation. With the 1844 general election in the United States approaching, the leadership in both the Democratic and Whig parties remained unequivocally anti-Texas. Texas-Mexico treaty options under consideration included an autonomous Texas within Mexico’s borders, or an independent republic with the provision that Texas should emancipate its slaves upon recognition.

Part of the politics of the whole should we annex/should we need did deal around slavery, as it’s already becoming a hotbed issue in the United States – but we’ll touch more on that in our discussion of the Civil War. Now – summarize, we’ve got the following situation:

  1. The US wants to annex Texas, but can’t garner the political support
  2. Mexico does NOT want Texas as part of the US
  3. Texas is tired of waiting on the US, and is in conversations to remain independent, but a part of Mexico

So, how did we get around this? We started negotiating in secret…


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The Annexation of Texas

US Secretary of State Upshur vigorously and secretly courted Texas diplomats to begin annexation talks, finally dispatching an appeal to Sam Houston in January 1845. In it, he assured Houston that, in contrast to previous attempts, the political climate in the United States, including sections of the North, was amenable to Texas statehood, and that a two-thirds majority in Senate could be obtained to ratify a Texas treaty.

As Secretary Upshur accelerated the secret treaty discussions, Mexican diplomats learned that US-Texas talks were taking place. Mexican minister to the U.S. Juan Almonte confronted Upshur with these reports, warning him that if Congress sanctioned a treaty of annexation, Mexico would break diplomatic ties and immediately declare war. Secretary Upshur evaded and dismissed the charges, and pressed forward with the negotiations. In tandem with moving forward with Texas diplomats, Upshur was secretly lobbying US Senators to support annexation, providing lawmakers with persuasive arguments linking Texas acquisition to national security and domestic peace. By early 1844, Upshur was able to assure Texas officials that 40 of the 52 members of the Senate were pledged to ratify the Tyler-Texas treaty, more than the two-thirds majority required for passage. Tyler, in his annual address to Congress in December 1843, maintained his silence on the secret treaty, so as not to damage relations with the wary Texas diplomats. Throughout, Tyler did his utmost to keep the negotiations secret, making no public reference to his administration’s single-minded quest for Texas.

Basically, Upshur was the equalivent of Littlefinger from Game of Thrones (for those listeners of mine who watch GoT), manipulating things behind the scenes and denying it in public.

The Tyler-Texas treaty was in its final stages when its chief architects, Secretary Upshur and Secretary of the Navy Thomas W. Gilmer, died in an accident aboard USS Princeton on February 28, 1844, just a day after achieving a preliminary treaty draft agreement with the Texas Republic. The Princeton disaster proved a major setback for Texas annexation, in that Tyler expected Secretary Upshur to elicit critical support from Whig and Democratic Senators during the upcoming treaty ratification process. Tyler selected John C. Calhoun to replace Upshur as Secretary of State and to finalize the treaty with Texas. The choice of Calhoun, a highly regarded but controversial American statesman, risked introducing a politically polarizing element into the Texas debates, but Tyler prized him as a strong advocate of annexation.

Now, many more political manuevers take place that we’ll just touch on a few of, for example: Senator Robert J Walker of Mississippi wrote a letter that was reproduced as a pamphlet calling for an immediate annexation of Texas. Walker argued that Texas could be acquired by Congress in a number of ways – all constitutional – and that the moral authority to do so was based on the precepts for territorial expansion established by Jefferson and Madison, and promulgated as doctrine by Monroe in 1823. – The Monroe Doctrine, is what he references here, which in summary states: further efforts by European nations to take control of any independent state in North or South America would be viewed as “the manifestation of an unfriendly disposition toward the United States.”

Senator Walker’s polemic offered analysis on the significance of Texas with respect to slavery and race. He envisioned Texas as a corridor through which both free and enslaved African-Americans could be “diffused” southward in a gradual exodus that would ultimately supply labor to the Central American tropics, and in time, empty the United States of its slave population.

This “safety-valve” theory “appealed to the racial fears of northern whites” who dreaded the prospect of absorbing emancipated slaves into their communities in the event that the institution of slavery collapsed in the South. This scheme for racial cleansing was consistent, on a pragmatic level, with proposals for overseas colonization of blacks, which were pursued by a number of American presidents, from Jefferson to Lincoln. Walker bolstered his position by raising national security concerns, warning that in the event annexation failed, imperialist Great Britain would maneuver the Republic of Texas into emancipating its slaves, forecasting a dangerous destabilizing influence on southwestern slaveholding states. The pamphlet characterized abolitionists as traitors who conspired with the British to overthrow the United States.

See what I mean when I say slavery is already a hot bed issue in the US?

So again, trying to keep the politics at a high level, let’s jump to the Benton Senate compromise, which I’ll spare you the details of, and leave you with: It was an idea for how to annex Texas and keep everyone happy(ish).

Senate and house legislators who had favored Benton’s renegotiated version of the Texas annexation bill had been assured that President Tyler would sign the joint house measure, but leave its implementation to the incoming Polk administration. But, during his last day in office, President Tyler, with the urging of his Secretary of State Calhoun, decided to act decisively to improve the odds for the immediate annexation of Texas. On March 3, 1845, with his cabinet’s assent, he dispatched an offer of annexation to the Republic of Texas by courier, exclusively under the terms of the Brown–Foster option of the joint house measure. Secretary Calhoun apprised President-elect Polk of the action, who demurred without comment. Tyler justified his preemptive move on the grounds that Polk was likely to come under pressure to abandon immediate annexation and reopen negotiations under the Benton alternative.

When President Polk took office on March 4, he was in a position to recall Tyler’s dispatch to Texas and reverse his decision. On March 10, after conferring with his cabinet, Polk upheld Tyler’s action and allowed the courier to proceed with the offer of immediate annexation to Texas. The only modification was to exhort Texans to accept the annexation terms unconditionally.

President Polk signed the legislation making the former Lone Star Republic a state of the Union on December 29, 1845

Okay – so we’re almost at the end of the episode, and we’ve yet to talk about anyone fighting…or even thinking about fighting. That’s right, I know but as the United States has grown up since the American Revolution the causes for conflicts get more political so it’s important for you, dear listeners, to understand WHY the fighting took place. But, I’ll leave you with a little bit… let’s talk the Battle of Palo Alto.

So, first of, why was Mexico mainly upset with the annexation of Texas? Simple. LAND.

There was a dispute over whether Texas ended at the Nueces River (Mexican claim) or the Rio Grande (U.S. claim).

Mexico severed relations with the United States in March 1845, shortly after the U.S. annexation of Texas. and in September of 1845 U.S. Pres. James K. Polk sent John Slidell on a secret mission to Mexico City to negotiate the disputed Texas border, settle U.S. claims against Mexico, and purchase New Mexico and California for up to $30 million. Mexican Pres. José Joaquín Herrera, aware in advance of Slidell’s intention of dismembering the country, refused to receive him. When Polk learned of the snub, he ordered troops under Gen. Zachary Taylor to occupy the disputed area between the Nueces and the Rio Grande, which will lead us to the first major engagement of the war… Palo Alto

Battle of Palo Alto

The Battle of Palo Alto, the first major engagement of the U.S.-Mexican War, was fought on May 8, 1846, just north of present-day Brownsville, Texas. Weeks earlier, U.S. General Zachary Taylor had led 3,000 troops to the Rio Grande and established Fort Texas opposite the Mexican City of Matamoros, as well as a supply base, Fort Polk, at Point Isabel about forty miles away on the Gulf Coast.

Mexican General Mariano Arista countered by bringing a 4,000-man force, the Army of the North, to Matamoros. He crossed the Rio Grande to the west and headed east to place his army between Taylor and his supply base, while putting Fort Texas under siege. Taylor managed to slip past Arista’s trap with the bulk of his forces on May 1, but left behind a small American garrison in dire straits. Taylor moved to Point Isabel, gathered all available supplies and reinforcements, and moved with a column of 2,200 men to the relief of Fort Texas. Arista, catching wind of this move, left forces to continue the siege while he led 3,400 troops north to intercept Taylor.

The two armies located each other at the scrubby crossroads of Palo Alto in the early afternoon of May 8. Each side deployed their troops, and the American troops stepped boldly forward to within 800 yards of the Mexicans. Almost immediately the superiority of the U.S. cannons and artillery tactics came to bear. Over the next three hours, the battle consisted mostly of a lopsided artillery duel. Attempts by the Mexican cavalry to turn the U.S. flank proved unsuccessful, and Arista ordered his troops out of action and moved to a strong defensive position at Resaca de la Palma. Arista lost between 250 and 400 men at Palo Alto, double the number of American losses.

Next week, we’ll jump into Polk’s response, the formal declaration of war, the capture of Monterry and the Battle of Buena Vista.

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