Final answer:
Patrick Cleburne's letter discusses the benefits of enlisting African American soldiers in the Union army during the Civil War.
Step-by-step explanation:
The letter written by Patrick Cleburne highlights the benefits of enlisting African American soldiers in the Union army during the Civil War. Cleburne argues that by allowing African Americans to fight, the Union would benefit from their strong military skills and loyalty, while also helping to weaken the Confederate forces.
Cleburne's letter ultimately influenced the Union's decision to recruit and deploy African American troops, contributing to their eventual victory.