President buchanan declared the south's secession from the union to be achildish. b. a radical approach. c. selfish. d. illegal.

D. illegal

The Northernors believed that the South had no right to secede even though their right to have slaves came under attack

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Contributing factors  leading  to the harlem renaissance were the great migration of african americans to northern cities, which concentratedambitious  people in places where they could encourage each  other, and the first world war, which had created new industrial work opportunities for tens of thousands of people.