Why did some northerners oppose the war? how did president lincoln respond when opposition turned violent?

 - The reason that the northerners opposed the war was that they had economic ties with the South and they feared that a war would negatively affect them financially. They also did not support the war because of their religious belief that violence and slavery were unjust and against God’s will.

 - When the opposition turned violent, President Lincoln sent his troops to border states keep order and suspended the right of habeas corpus, and jailed people who opposed him.