The Controversy Over Slavery's Expansion In The United States?

Manifest Destiny gave Americans the idea that they had the right to expand through the continent to spread the freedom and liberty they had come to know. This freedom and liberty did not apply to all. A significant numbers of Americans viewed themselves as superior to the people of the unsettle regions, namely the Indians and the Mexicans. This idea of racial superiority was also the underlying issue within the debate of slavery. The expansion throughout the continent would only serve to reopen the controversy over slavery and create further tension between the North and South. As long as there was a fundamental difference in beliefs throughout the country, conflict would continue.
The possible acquisition of land from Mexico led to another point of contention in the slavery debate. When a bill surfaced to appropriate funding to purchase peace with Mexico during the war, a provision was added to prohibit slavery in any newly acquired territory. Southern opposition soon surfaced claiming that all Americans had equal rights in new lands. They argued slaves were their property and they had to right to do with their property as they see fit. A possible solution was offered by extended the Missouri Compromise line but the debate waged on. (American History, p359)
The gold rush in California further complicated the issue of slavery. When gold

First, its population was bigger by almost four times when compared to the non-slave population of the south. This led to not only manpower for its army, but also the workforce to supply this army. This workforce and heavy industrialization allowed the North to supply all of its own war materials. The infrastructure was also superior in the North. The railroad was more integrated and they had twice as much trackage. The North also had naval superiority which proved a valuable resource in assisting with field operations. (American History,