Psychological warfare in the broad sense, consists of the application of parts of the science called psychology to the conduct of war; in the narrow sense, psychological warfare comprises the use of propaganda against an enemy, together with such military operational measures as may supplement the propaganda. Propaganda may be described, in turn, as organized persuasion by non-violent means. War itself may be considered to be, among other things, a violent form of persuasion. Thus if an American fire-raid burns up a Japanese city, the burning is calculated to dissuade the Japanese from further warfare by denying the Japanese further physical means of war and by simultaneously hurting them enough to cause surrender. If, after the fire-raid, we drop leaflets telling them to surrender, the propaganda can be considered an extension of persuasion--less violent this time, and usually less effective, but nevertheless an integral part of the single process of making the enemy stop fighting. Neither warfare nor psychology is a new subject. Each is as old as man. Warfare, being the more practical and plain subject, has a far older written history. This is especially the case since much of what is now called psychology was formerly studied under the heading of religion, ethics, literature, politics, or medicine. Modern psychological warfare has become self-conscious in using modern scientific psychology as a tool. In World War II the enemies of the United States were more fanatical than the people and leaders of the United States. The consequence was that the Americans could use and apply any expedient psychological weapon which either science or our version of common sense provided. We did not have to square it with Emperor myths, the Führer principle or some other rigid, fanatical philosophy. The enemy enjoyed the positive advantage of having an indoctrinated army and people; we enjoyed the countervailing advantage of having skeptical people, with no inward theology that hampered our propaganda operations. It is no negligible matter to be able to use the latest findings of psychological science in a swift, bold manner. The scientific character of our psychology puts us ahead of opponents wrapped up in dogmatism who must check their propaganda against such articles of faith as Aryan racialism or the Hegelian philosophy of history.