With the Louisiana Purchase Agreement encompassing present-day Louisiana, Arkansas, Missouri, Kansas, and numerous other states, in essence, the expansion pushed toward the eventual acquisition of Texas (another slave state), and let's not forget about Nebraska (also carved from the Louisiana Purchase), since it is forever known by the Kansas-Nebraska Act of 1854, an act that focused solely on slavery and its expansion, too. After fighting in the Mexican-American War (1846-1848) and witnessing, among many US gains, the state of Texas as a result of said conflict, General US Grant (later served as 18th US President; Lincoln was 16th) would lead that famous Army of the Potomac and witness tens-of-thousands of deaths during the American Civil War (1861-1865). Perhaps Grant, after the bloody Civil War and after serving as President, had a deeper and more profound insight when he wrote of the Mexican-American War and its results: "Generally, the officers of the army were indifferent whether the annexation was consummated or not; but not so all of them. For myself, I was bitterly opposed to the measure, and to this day regard the war, which resulted, as one of the most unjust ever waged by a stronger against a weaker nation. It was an instance of a republic following the bad example of European monarchies, in not considering justice in their desire to acquire additional territory." Grant's words are harsh reminders of Popular Sovereignty and Manifest Destiny.
Louisiana Purchase Agreement
The Louisiana Purchase nearly doubled the size of the
Map of United States and its Acquisition of Territory: Expansionism History
Treaty of Amity; Treaty of Adams-Onis; Acquisition of Florida