Answer:
The large number of deaths in the Union's army was the main reason for the government to allow the enlistment of African-American citizens.
Explanation:
Lincoln did not approve of the idea of allowing African Americans to be enlisted in the army because he feared that this would infuriate southern states and worsen the polarization that the country faced on their behalf. However, once the civil war started, both armies suffered many deaths, drastically decreasing the number of viable soles for the battle, thereby allowing African Americans to enlist so that the armies had a sufficient number of soldiers.
