President Abraham Lincoln understood that main objective of the Union armies was to capture Richmond. destroy the Confederate armies' ability to fight. occupy Confederate territory. control Confederate ports. free Southern slaves.

destroy Confederate armies' ability to fight

Explanation:

During the American Civil war, which broke on 1861, the Confederate armies was the army of the Confederate states of America. These armies were fighting against the Armies of United States. During the war, the union armies suffered a higher mortality rate as compared to the Confederate armies. Abraham Lincoln understood that the main air of the Union armies was to attacked and destroy the moral and fighting ability of the Confederate armies.