books.google.com - This volume poses "what if" questions about ten crucial "tipping points" in the history of U.S. expansionism between 1800 and the Civil War. It not only describes what happened--in the case of Lewis and Clark, the War of 1812, the Monroe Doctrine, railroads and telegraphs, the Mexican War, the gold rush,...http://books.google.com/books/about/Manifest_Destiny_and_the_Expansion_of_Am.html?id=ka6LxulZaEwC&utm_source=gb-gplus-shareManifest Destiny and the Expansion of America
