What reasons did southerners give to support secession?

Southerners justified secession primarily by asserting their rights to self-determination and their belief in states' rights, arguing that the federal government was overstepping its authority. They claimed that secession was a necessary response to perceived threats against their way of life, particularly regarding slavery, which they viewed as essential to their economy and social order. Additionally, many southerners believed that their cultural identity and political autonomy were under siege by a Northern-dominated federal government.