The years 1840 to 1890 were a period of great growth for the United States. It was during this time period that the United states came to the conclusion that it had a manifest destiny, that is, it was commanded by god to someday occupy the entire North American continent. One of the most ardent followers of this belief was President James K. Polk. He felt that the United States had the right to whatever amount of territory it chose to, and in doing this the United States was actually doing a favor for the land it seized, by introducing it to t ....