How and why did the ideas of an American empire change from the 1790s to the 1850s? Did the definition of \”American Exceptionalism\” change as well?

This essay must use documentary evidence from the Manifest Destiny and American Territorial Expansion book.\r\nBe sure to use the Rule of Three in this assignment. You should have an intro with thesis statement, at least three paragraphs in the body (one for each point of the thesis) and a conclusion. The best way to organize is to use political, economic, and social as your thesis points.