Lincoln's strategy, at first, was to define the civil war as a fight about

human dignity and civil rights
ending slavery
preserving the united states
preserving slavery

Lincoln didn't want other states to secede, because that would make a bad example for other states that didn't like the government. In a speech, Lincoln described that his goal was to preserve the United States, because during that time, it wasn't united.

Lincoln's strategy, at first, was to define the Civil War as a fight about preserving the United States.

Have a nice day! :)