What does the term "secession" refer to in American history?

The term "secession" in American history specifically refers to the act of withdrawing from the United States, particularly in the context of the Southern states during the Civil War era. This action was primarily motivated by issues surrounding states' rights and slavery. When several Southern states chose to secede from the Union in the early 1860s, they formed the Confederate States of America, which ultimately led to the Civil War. Secession was a significant and contentious moment in American history, representing a drastic measure taken by those who felt their rights and way of life were threatened by federal policies.

In contrast, the other terms do not accurately represent the concept of secession. Political alliances with foreign nations, participation in new trade agreements, and forming new colonies relate to different historical events and aspects of governance that do not encompass the idea of leaving the Union. Thus, the understanding of secession is rooted in the context of the states' decision to break away from the United States during a pivotal conflict in the nation’s history.