Extravagance and wastefulness is somewhat rooted in the American character, because of our mode of life. When our men enter military service, there is a strong holdover of their prodigal civilian habits. Even under fighting conditions, they tend to be wasteful of drinking water, food, munitionment and other vital supply. When such things are made _too_ accessible, they tend to throw them away, rather than to conserve them in the general interests. This is a distinct weakness during combat, when conservation of all supply is the touchstone of success. The regulating of all supply, and the preventing of waste in any form, is the prime obligation of every officer. XIX Under the conditions of battle, any extra work, exercise, maneuver or _marching which does not serve a clear and direct operational purpose_ is unjustifiable. The supreme object is to keep men as physically fresh and mentally alert as possible. Tired men take fright and are half-whipped before the battle opens. Worn-out officers cannot make clear decisions. The conservation of men's powers, not the exhaustion thereof, is the way of successful operation. XX When forces are committed to combat, it is vital that not one unnecessary pound be put on any man's back. Lightness of foot is the key to speed of movement and the increase of firepower. In judging of these things, every officer's thought should be on the optimistic side. It is better to take the chance that men will manage to get by on a little less than to overload them, through an over-cautious reckoning of every possible contingency, thereby destroying their power to do anything effectively. XXI Even a thorough training and long practice in weapons handling will not always insure that a majority of men will use their weapons freely and consistently when engaging the enemy. This is particularly true of Americans. In youth they are taught that the taking of human life is wrong. This feeling is deep-rooted in their emotions. Many of them cannot shake it off when the hour comes that their own lives are in danger. They fail to fire, though they do not know exactly why. In war, firing at an enemy target can be made a habit. Once required to make the start, because he is given personal and intelligent direction, any man will find it easier to fire the second and third time, and soon thereafter his response will become automatic in any tactical situation. When engaging the enemy, the most decisive task of all junior leaders is to make certain that _all_ men along the line are employing their weapons, even if this means spending some time with each man and directing his fire. Reconnaissance and inspection toward this end, particularly in the early stages of initial engagement, are far more important than the employment of weapons by junior leaders themselves, since this latter tends to distract their attention from what the men are doing. XXII