In the early nineteenth century, the United States turned its idealistic gaze southward, imagining a legacy of revolution and republicanism it hoped would dominate the American hemisphere. From pulsing port cities to Midwestern farms and southern plantations, an adolescent nation hailed Latin America's independence movements as glorious tropical reprises of 1776. Even as Latin Americans were gradually ending slavery, U.S. observers remained energized by the belief that their founding ideals were triumphing over European tyranny among their -sister republics.- But as slavery became a violently...