Furthermore, propaganda must have a known purpose. This element must be included in the definition; a great deal of communication, both in wartime and in peacetime, arises because of the pleasure which it gives to the utterer, and not because of the result it is supposed to effect in the hearers. Sending the Japanese cartoons of themselves, mocking the German language, calling Italians by familiar but inelegant names--such communications cropped up during the war. The senders got a lot of fun out of the message but the purpose was unintelligently considered. The actual effect of the messages was to annoy the enemy, stiffening his will-to-resist. (Screams of rage had a place in primitive war; in modern military propaganda they are too expensive a luxury to be tolerated. Planned annoyance of the enemy does, of course, have its role--a minor, rare and special one.) "Psychological warfare" is simple enough to understand if it is simply regarded as application of propaganda to the purposes of war, as in the following definition: _Psychological warfare comprises the use of propaganda against an enemy, together with such other operational measures of a military, economic, or political nature as may be required to supplement propaganda._ In this sense, "psychological warfare" is a known operation which was carried on very successfully during World War II under the authority of the Combined and Joint Chiefs of Staff. It is in this sense that some kind of a "Psychological Warfare Unit" was developed in every major theater of war, and that the American military assimilated the doctrines of "psychological warfare." However, this is only one of several ways of using the term, "psychological warfare." There is, in particular, one other sense, in which the term became unpleasantly familiar, during the German conquest of Europe, the sense of _warfare psychologically waged_. In the American use of the term, psychological warfare was the supplementing of normal military operations by the use of mass communications; in the Nazi sense of the term, it was the calculation and execution of both political and military strategy on studied psychological grounds. For the American uses, it was modification of traditional warfare by the effective, generous use of a new weapon; for the Germans it involved a transformation of the process of war itself. This is an important enough distinction to warrant separate consideration.