The United States of America before the Mexican War was slowly being torn into two sections, North and South, over the issue of slavery. The nation would be changed politically, sectionally and militarily. At first, the United States was equally proportioned in the number of slave and free states, but after the Mexican War the representation of each region was forever lost and the end result being the American Civil War.
The 1800s was a time of change for America. Most Americans were supporters of expanding the Union to make a larger stronger country, but some also saw the Mexican War as a sheer scheme to expand slavery; however, the Mexican War was seen as something that was necessary to settle disputes between the two countries, and through the support of the "Manifest Destiny," the unresolved conflict that took place between the Texans and Mexicans in the early 1800's, and Polk's failed efforts for peace between Mexico and the United States, it can be established that the Mexican War was in the National interest.
The Mexican war between the U.S. and Mexico was started because of a Mexican attack on American troops along the southern border of Texas on April 25, 1846. After Winfield Scott occupied Mexico City on September 14,1847, a few months later a peace treaty was signed between Mexico and the U.S. A dictatorial Centralist government in Mexico began the war because of the U.S. annexation (1845) of Texas, which Mexico continued to claim despite the establishment of the independent republic of Texas 10 years before. Another possible cause for the war may be that the U.S. brought on the war by annexing Texas and, just to make Mexico angry, by stationing an army at the mouth of the Rio Grande.
International borders have always...