Why did Americans fail to resolve their differences over slavery?

What triumphs did the late 19th century witness in the realms of industrial growth, urbanization, and technological innovation? what challenges did these developments pose for urban dwellers, workers, and recent immigrants? how did city officials and everyday citizens respond to these challenges?

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When president johnson vetoed a law that would extend the freedmen’s bureau, congress reacted by supporting the veto and closing the freedmen’s bureau. writing a new law to show support for the black codes. overriding the veto and expanding the agency’s powers. drafting a law to prevent african americans from voting.