5.3+Manifest+Destiny+&+Mexican+American+War
Topic 5.3: Manifest Destiny and the Mexican-American War
Background
Manifest Destiny was the belief that the expansion of the US throughout the American continents was both justified and inevitable.
The Southern rebellion was largely influenced by the Mexican War as articulated by Ulysses S. Grant.
Causes of the War
Annexation of Texas
The annexation of Texas by the US led to diplomatic issues with Mexico, inciting anger.
President Polk's aim to expand the nation to the Pacific fueled tensions.
Polk's Diplomacy
In 1845, Polk sent diplomat John Slidell to persuade Mexico to sell California and New Mexico and settle the Texas border dispute.
Slidell's mission was unsuccessful; Mexico refused to sell California and claimed the Texas border was at the Nueces River.
Polk and Slidell insisted the border was along the Rio Grande.
Immediate Causes
Polk ordered General Zachary Taylor to move troops toward the Rio Grande, amidst claims of American territory.
On April 24, 1846, Mexican forces attacked and killed 11 American troops, which Polk used as justification for war.
Despite Whig opposition, Congress approved a war resolution.
Military Campaigns
General Stephen Kearney
Led a smaller American force (1,500 troops) to successfully capture New Mexico and Southern California.
John C. Frémont
With a small force, he led a revolt in June 1846 against Mexican rule in California, declaring it the Bear Flag Republic.
Zachary Taylor's Campaign
Taylor's 6,000 troops defeated the Mexican army in Texas and secured a major victory at Buena Vista in February 1847.
General Winfield Scott's Invasion
Scott led 14,000 troops to invade central Mexico, capturing Vera Cruz and Mexico City by September 1847.
Consequences of the War
Military Disaster for Mexico
From the outset, the war was disastrous for Mexico; unwilling to negotiate until forced after the fall of Mexico City.
Treaty of Guadalupe Hidalgo (1848)
Terms included recognition of the Rio Grande as the Texas border and ceding of California and New Mexico to the U.S. (Mexican Cession).
The U.S. paid $15 million and assumed claims of American citizens against Mexico.
Political divisions arose, with Whigs opposing the treaty on moral grounds related to slavery and Southern Democrats favoring a larger acquisition of Mexico.
The Wilmot Proviso
Proposed by Congressman David Wilmot in 1846 to prohibit slavery in newly acquired territories.
Passed in the House but was consistently defeated in the Senate.
This initiative sparked conflicts over the extension of slavery into new territories, increasing North-South tensions.
Prelude to Civil War?
The war raised sectional debates over slavery, leading many Northerners to view it as a Southern effort to expand slave power.
The Wilmot Proviso marked the beginning of escalating political conflict leading to the Civil War.
Topic 5.3: Manifest Destiny and the Mexican-American War
Background
Manifest Destiny was the belief that US expansion across the Americas was justified and inevitable. It influenced the Southern rebellion, as noted by Ulysses S. Grant.
Causes of the War
Annexation of Texas: The annexation led to tensions with Mexico as President Polk aimed to expand to the Pacific.
Polk's Diplomacy: In 1845, diplomat John Slidell attempted to buy California and New Mexico, but Mexico refused to sell.
Immediate Causes: Polk ordered troops to the Rio Grande; a Mexican attack on April 24, 1846, killing 11 Americans justified war.
Military Campaigns
General Stephen Kearney: Captured New Mexico and Southern California.
John C. Frémont: Led a revolt in California in June 1846, declaring the Bear Flag Republic.
Zachary Taylor: Defeated Mexican forces in Texas with a major victory at Buena Vista in February 1847.
General Winfield Scott: Invasion of central Mexico finished with the capture of Vera Cruz and Mexico City by September 1847.
Consequences of the War
Military Disaster for Mexico: Reluctant to negotiate until forced after Mexico City fell.
Treaty of Guadalupe Hidalgo (1848): Established the Rio Grande as Texas' border and saw California and New Mexico ceded to the US, with $15 million paid to Mexico.
Political Divisions: Whigs opposed the treaty on moral grounds regarding slavery, while Southern Democrats sought a larger acquisition.
The Wilmot Proviso: Proposed to ban slavery in new territories, passing in the House but failing in the Senate, fueling North-South tensions.
Prelude to Civil War?
The war intensified debates over slavery, with Northerners seeing it as a Southern push to expand slavery. The Wilmot Proviso marked rising political conflict leading to the Civil War.