Unarmed Defense for the American Soldier - 1942 - FM 21-150 (First Part)

The object of this training is to develop the soldier in the art of unarmed self-defense, and to improve his skill in the use of his basic weapons, through speeded reflexes. Confidence in his own ability unarmed, like confidence in his weapons, makes a man a better soldier.

The average soldier, if trained only in the use of his weapons, loses his effectiveness if these weapons are lost or fail to function. However, particularly in hand-to-hand fighting, if a soldier should be deprived of his weapon or have it destroyed, he is at the mercy of the enemy. This appears to apply mainly to the Infantry, and probably the greatest value of American unarmed defense will be to that arm. Nevertheless, in these days of fluid warfare, troops in rear echelons, artillery, and antitank units might find themselves in hand-to-hand combat with no defensive weapons except sidearms and bare hands.