What event triggered the war between the union and the confederacy

How did the supreme court decision in the slaughterhouse cause have an affect american business

By choosing to resupply fort sumter, abraham lincoln risked a. abandonment of the fort by union soldiers. b. abandonment of the fort by confederate soldiers. c. the appearance of giving in to confederate secession. d. armed conflict with southern soldiers.

Why is it important that dr. luther king jr. use non-violent protest to create social change?