Final answer:
African Americans were not allowed to fight for the Union at the start of the war due to lack of trust, legal considerations, and the size of the Union army.
Step-by-step explanation:
At the start of the war, African Americans were not allowed to fight for the Union due to several reasons. Firstly, Union generals did not initially trust African Americans and were unsure of their loyalty. Congress also refused to allow them to join because they were still legally considered property, and any harm to them would be seen as destruction of property. Moreover, the Union army was initially large enough and did not need African Americans to fight, so they were assigned civilian jobs to support the army.
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