There were many country-splitting issues that characterized the United States in the 1800s. A major one of these was Manifest Destiny, the belief that the United States was destined to extend its territory west to the Pacific Ocean. The country separated as many people supported the idea, and many opposed it. There were both positive and negative aspects to expansion in the era of Manifest Destiny.
             Many Americans supported the belief of Manifest Destiny. Northerners who were troubled by economic instability and overpopulation believed that Manifest Destiny would make urban areas less crowded. They also said that with more land, the United States could extend railroads, supporting trade from east to west. Expansion would also give access to the Pacific Ocean, which would open up overseas trade. Southern expansionists, in hope of convincing Northerners, said that expansion would help end slavery because it would shift the slave population westward. The South argued that expansion would free up a lot of land for agriculture and manufacturing, which would help the stability of the economy. Supporters said that expansion would be good for America in the same way the Louisiana Purchase had been. They argued that expanding would help rid the United States of foreign influences and at the same time, make America look stronger in the eyes of the world.
             There were negative aspects to Manifest Destiny. Americans who were against expansion debated that it was unconstitutional. They said that there was nowhere in the Constitution that supported the extension of boundaries. Also, when America received the Mexican Cession, the Mexicans living on the land automatically became U.S. citizens. Though they were legal citizens, they were not treated as such. The Americans treated them as second class citizens in the same way that Britain had once treated Americans. This is ironic because this was the main reason that the United States had beco...