The primary reason President Abraham Lincoln waged war against the South was to preserve the Union and prevent the secession of the southern states. After his election in 1860, several southern states began to secede from the United States due to perceived threats to their economic, social, and political interests, especially regarding the issue of slavery. Lincoln, along with many in the North, believed that secession was unconstitutional and feared that it would lead to the disintegration of the nation. Therefore, the Civil War erupted as Lincoln sought to reunify the divided country and maintain the integrity of the Union. It is important to note that while Lincoln's primary objective was to preserve the Union, the issue of slavery did become a significant factor as the war progressed, leading to the Emancipation Proclamation and the eventual abolition of slavery in the United States.
