America seemed poised for an era of growth. President T. Jefferson proposed a vision for the nation that he took steps to make possible, including the purchase of Louisiana. As Americans continued to move West, conflict with Native Americans was unavoidable, and the federal government developed strongly pro-settler Indian policies. New territories became states, creating further political and sectional tensions as plans for the development of these new states were put forward. With the announcement of the Monroe Doctrine, President Monroe modified the definition of “frontier” and the concept of “Manifest Destiny” emphasized America’s sense of its mission in the world. By 1844, the politics of frontier expansion caused a war with Mexico which
