The Battle of Milliken's Bend was significant as it disproved the belief that formerly enslaved men would not make good soldiers. Edwin Stanton's letter emphasizes how this battle demonstrated the courage and capacity of African American troops. Their success helped change perceptions about their role in military service during the Civil War. ;
The Battle of Milliken's Bend was crucial in demonstrating that formerly enslaved men could be effective soldiers, directly challenging prevailing prejudices of the time. Edwin M. Stanton's letter indicates that this battle helped prove their courage and capacity in military service. Thus, the correct answer is D: It disproved the belief that formerly enslaved men would not be good soldiers.
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