Final answer:
Abraham Lincoln's main goal of the Civil War was the preservation of the Union, not the abolition of slavery. However, he recognized the importance of emancipation in weakening the Confederate South. The naval blockade was an effective strategy used by Lincoln to hamper Confederate supplies.
Step-by-step explanation:
During the early years of the Civil War, Abraham Lincoln's main goal was the preservation of the Union, not the abolition of slavery. He believed that if the Union remained intact, slavery would eventually die out on its own. However, as the war progressed, Lincoln recognized the significance of emancipation in order to weaken the Confederate South. By issuing the Emancipation Proclamation in 1863, Lincoln aimed to free slaves in Confederate territory and gain support from abolitionists in Europe. Additionally, the naval blockade of the South was an important strategy implemented by Lincoln to cut off supplies and weaken the Confederate economy during the war.