What does Stevens warn might happen if the situation of formerly enslaved African Americans does not improve?

future rebellion might occurred.

Explanation:

Thaddeus Stevens  was a government representatives who was a major advocate to improve the living conditions of African American during the reconstruction period.

After the civil war was over, the government in southern states still openly discriminated the African Americans regardless of the orders from the federal government to treat them as fellow citizens.

Thaddeus Stevens voiced up his disdain to the southern government's action publicly. stating that if the southern government keep treating the former slaves like that, they will reach a breaking point where they'll start violently rebelling against the southern people and it will cause a lot of unnecessary death.

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