Secession came even though lincoln posed no immediate threat to slavery in the south, the democrats still controlled congress, and the supreme court was decidedly pro-southern. why then did seven southern states secede after lincoln's election?

In his inaugural address, Lincoln promised not to interfere with the institution of slavery where it existed, and pledged to suspend the activities of the federal government temporarily in areas of hostility. However, he also took a firm stance against secession and the seizure of federal property. The government, insisted Lincoln, would “hold, occupy, and possess” its property and collect its taxes.

it's not the readmission