This discussion addresses the following outcomes:

Define the concept of "Manifest Destiny" and examine its role in American expansionism into Texas and other Mexican territories. (CO#1, #3)

Explain the significance of the Mexican-American War in the sectional controversy over slavery (CO#3, #5)

Expansion is a major theme of the United States' history. As a young, energetic country, the United States also saw itself as gifted by Providence to spread out into neighboring lands.

The migration of Americans into Mexican territory opened a new chapter in that story. Texan independence from Mexico seemed to fulfill the promise of Manifest Destiny, not just in terms of land but in the spread of American ideals. However, the Mexican-American War also unsettled a sectional balancing act regarding slavery.

In preparation for our discussion be sure to read and view the Module Notes, Chapter 12: "Manifest Destiny ", section II of Chapter 13: "II. Sectionalism in the Early Republic ", and Mexico: Battle for North America .

In addition please read the following primary sources: Lundy, B. (1836), An Abolitionist Calls Slavery the True Cause of the Texas Revolution , Polk, J.K. (1846), Polk's Message on War with Mexico . Wilmot, D. (1847), "A Congressman Pleads the Case of White Men ," Harrison, W. H. (1838), William Henry Harrison Discusses the Politics of Slavery , and O'Sullivan, J. L. (1839), Manifest Destiny .

Using the primary and secondary source materials above as evidence, consider the following in a post of at least 250 words:

How did the concept of Manifest Destiny rationalize US expansion into Texas and other Mexican territories?

Explain the arguments by both anti- and pro-slavery proponents about the Mexican-American War's possible impact on American politics and sectional relations.