American Civil War Principles

Battle of Gettysburg

The American Civil War demonstrated the principles of warfare, which are historic military instructions for commanders and military officers.

The American Civil War was an excellent demonstration of the principles of war, which are historic military instructions on strategy, tactics, and operations. The principles include mass, maneuver, objective, offensive, security, simplicity, surprise, unity of command, and economy of force. The acronyms for remembering these principles are MOUSE and MOSS. These principles were derived from the military philosophies of Karl Von Clausewitz, Liddell Hart, Napoleon, Sun Tzu, and JFC Fuller. Throughout the American Civil War’s deadly history at least one or more of these principles were executed by either Confederate or Union generals involved in the conduct and prosecution of this war.

The Principle of Mass

The principle of mass involves the concentration of combat power at the decisive place and time. Mass does not mean “more men.” The Confederate Army achieved military superiority over the numerically superior Union Army during the early years of the American Civil War because the Confederate Army had superior generalship, leadership, morale, and training. The principle of mass is usually gained by superior generalship with superior weapons and tactics.

The Principle of Objective

The principle of objective involves directing every military operation towards a clearly defined objective. The proper objective in battle is the destruction of the enemy’s combat forces. However, to execute this agenda subordinate commanders must be given “terrain objectives” toward which they move. Thus, Richmond was not a proper terrain objective for McClellan’s army in 1862 because capturing it would not necessarily destroy the Confederate Army and the loss of Richmond in 1862 would not have meant defeat of the Confederacy. It was a proper terrain objective for General Grant in 1864-65 because it had become so important by that time that General Lee was forced to defend it even if it meant destruction of his army. While Grant’s objective was Lee’s Army of Northern Virginia, by directing his efforts toward Richmond he forced Lee to stand and fight him for its defense.

Unity of Command

The principle of the unity of command requires that for every objective, ensure unity of effort is under one responsible commander. The Union flagrantly violated this principle after the Battle of Kernston. Stonewall Jackson’s Shenandoah Valley campaign taught Lincoln and Stanton their lesson, and Unity of Command was obtained by creating Pope’s Army of Virginia.


The principle of surprise demonstrates how to strike the enemy at a time or place, or in a manner, for which the adversary is unprepared. Tactical or strategic surprise does not always mean the unexpected. Thus, an army may be “surprised” by an attack it has seen coming for several hours if this attack is too formidable for it to resist by itself and if no other combat units are within supporting distance. The fate of the XI Corps at Chancellorsville is an example. The principle of war known as “Security” may be defined as all measures taken to avoid “Surprise.”

Economy of Force

The principle of economy of force involves allocating minimum essential combat power to secondary efforts. Note that the principle pertains to “secondary efforts,” and it is the means by which a superior general achieves “mass”. Confederate Generals were able to achieve economy of force during the early years of the American Civil War with inferior numbers because of their superior Generalship. Mass and Economy of Force are similar warfare principles.


The principle of maneuver involves placing the enemy in a position of disadvantage through the flexible application of combat power. General Stonewall Jackson demonstrated this principle during the Battle of Chancellorsville in May 1863. The Union army in Virginia, led by Joseph Hooker, attempted to encircle and destroy the Confederate Army of Northern Virginia, led by Robert E. Lee. The Union army was surprised by a flanking force under the command of Stonewall Jackson. Three days of fighting ended in a Union retreat north of the Rappahannock River. The Union army lost more than 17,000 men in a force of 130,000; the Confederate Army lost about 12,000, including Jackson, in a force of 60,000.


The principle of offensive involves seizing, retaining, and exploiting the initiative. General George B McClellan failed to execute this principle in the Battle of Antietam on 17 September 1862. After the Confederate Army’s victory in the Second Battle of Bull Run, Gen. Robert E. Lee moved his troops into Maryland with an eye to capturing Washington, D.C. They were stopped by Union troops under George B. McClellan at Antietam Creek, Maryland. Confederate casualties numbered some 13,700, and Union losses were about 12,400. McClellan was criticized for allowing Lee’s forces to retreat to Virginia, but the victory encouraged President Abraham Lincoln to issue a preliminary Emancipation Proclamation.


The principle of security reminds commanders to never permit the enemy to acquire an unexpected advantage. For example, the Union Army was surprised at Shiloh due to insufficient security. Union forces under Ulysses S. Grant, including William T. Sherman, camped on the Tennessee River at Pittsburg Landing, Tennessee, in preparation for an offensive. Confederate forces under A.S. Johnston and P.G.T. Beauregard attacked, surprising the Union troops and forcing their retreat, though Johnston was mortally wounded. A Union counterattack the next day regained the lost ground, and the Confederates withdrew to Corinth, Mississippi. Both sides claimed victory, but the battle was considered a Confederate defeat. Each side suffered about 10,000 casualties.


The principle of simplicity involves a good, simple plan, with concise, clear orders designed to minimize the chance of confusion where every tactical element of the combat operation is understandable to the participants. Gen. Irvin McDowell violated the principle of simplicity in the First Battle of Bull Run on 21 July 1861 because his troops were too green to execute properly the maneuver he prescribed.


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  2. Axelrod, Alan; American History; Alpha Books Publications, 2000.
  3. Dunnigan, James, F.; How to Make War; William Marrow Publications, 1993.
  4. Zimmerman, Dwight, Jon; The Book of War; Tess Press Publications, 2008.