American Republics by Alan Taylor is an accessible book for a broad audience by a professional historian. It addresses the period after the Revolution when the U.S.A. expanded to occupy the midwest, the Great Plains, the Southwest and the Pacific Northwest. The book discusses the issues on which many Americans shared the same attitudes. Americans favoured expansion of the boundaries of American and of trade. While many Americans opposed slavery, few wanted to associate with Blacks (or immigants or Catholics). Americans viewed the resistance of indigenous Americans to settlement as an issue that was to be resolved in favour of settlement by Americans, by force.
It explains the war of 1812, the Louisiana purchase, the Seminole Wars and the annexation of Florida as an attempt by the USA to extend its boundaries and world trade while Britain, France and Spain were occupied with the Napoleonic Wars and were not devoting signicant military force to defend commercial interests in North America.