The United States Armed Forces use the following nine principles of war in training their officers:
* Objective – Direct every military operation toward a clearly defined, decisive and attainable objective. The ultimate military purpose of war is the destruction of the enemy’s ability to fight and will to fight.
* Offensive – Seize, retain, and exploit the initiative. Offensive action is the most effective and decisive way to attain a clearly defined common objective. Offensive operations are the means by which a military force seizes and holds the initiative while maintaining freedom of action and achieving decisive results. This is fundamentally true across all levels of war.
* Mass – Mass the effects of overwhelming combat power at the decisive place and time. Synchronizing all the elements of combat power where they will have decisive effect on an enemy force in a short period of time is to achieve mass. Massing effects, rather than concentrating forces, can enable numerically inferior forces to achieve decisive results, while limiting exposure to enemy fire.
* Economy of Force – Employ all combat power available in the most effective way possible; allocate minimum essential combat power to secondary efforts. Economy of force is the judicious employment and distribution of forces. No part of the force should ever be left without purpose. The allocation of available combat power to such tasks as limited attacks, defense, delays, deception, or even retrograde operations is measured in order to achieve mass elsewhere at the decisive point and time on the battlefield.
* Maneuver – Place the enemy in a position of disadvantage through the flexible application of combat power. Maneuver is the movement of forces in relation to the enemy to gain positional advantage. Effective maneuver keeps the enemy off balance and protects the force. It is used to exploit successes, to preserve freedom of action, and to reduce vulnerability. It continually poses new problems for the enemy by rendering his actions ineffective, eventually leading to defeat.
* Unity of Command – For every objective, seek unity of command and unity of effort. At all levels of war, employment of military forces in a manner that masses combat power toward a common objective requires unity of command and unity of effort. Unity of command means that all the forces are under one responsible commander. It requires a single commander with the requisite authority to direct all forces in pursuit of a unified purpose.
* Security – Never permit the enemy to acquire unexpected advantage. Security enhances freedom of action by reducing vulnerability to hostile acts, influence, or surprise. Security results from the measures taken by a commander to protect his forces. Knowledge and understanding of enemy strategy, tactics, doctrine, and staff planning improve the detailed planning of adequate security measures.
* Surprise – Strike the enemy at a time or place or in a manner for which he is unprepared. Surprise can decisively shift the balance of combat power. By seeking surprise, forces can achieve success well out of proportion to the effort expended. Surprise can be in tempo, size of force, direction or location of main effort, and timing. Deception can aid the probability of achieving surprise. …
* Simple – Prepare clear, uncomplicated plans and concise orders to ensure thorough understanding. Everything in war is very simple, but the simple thing is difficult. To the uninitiated, military operations are not difficult. Simplicity contributes to successful operations. Simple plans and clear, concise orders minimize misunderstanding and confusion. Other factors being equal, parsimony is to be preferred.
Officers in the U.S. Military sometimes use the acronyms “MOSS COMES”, “MOSS MOUSE”, “MOOSE MUSS”, “MOUSE MOSS”, “MOM USE SOS”, or “SUMO MOSES” to remember the first letters of these nine principles.
(US Army Field Manual FM 3-0)