Each side tried to find ways to maximize its advantages. Essentially, the Confederacy adopted a defensive strategy, with occasional thrusts into the North. General Robert E. Lee, the leading southern commander, was a brilliant battlefield tactician who felt confident of his ability to fend off attacks by larger Union forces. He hoped that a series of defeats would weaken the North’s resolve and lead it eventually to abandon the conflict and recognize southern independence.
Lincoln’s early generals found it impossible to bring the Union’s advantages in manpower and technology to bear on the battlefield. In April 1861, the regular army numbered little more than 15,000 men, most of whom were stationed west of the Mississippi River. Its officers had been trained to lead small, professional forces into battle, not the crowds of untrained men who assembled in 1861. The North also suffered from narrowness of military vision. Its generals initially concentrated on occupying southern territory and attempting to capture Richmond, the Confederate capital. They attacked sporadically and withdrew after a battle, thus sacrificing the North’s manpower superiority and allowing the South to concentrate its smaller forces when an engagement impended.
Well before his generals did, Lincoln realized that simply capturing and occupying territory would not win the war, and that defeating the South’s armies, not capturing its capital, had to be the North’s battlefield objective. And when he came to adopt the policy of emancipation, Lincoln acknowledged what Confederate vice president Alexander H. Stephens had already affirmed: slavery was the “cornerstone” of the Confederacy. To win the war, therefore, the Union must make the institution that lay at the economic and social foundation of southern life a military target.