Individual political communities may indeed enjoy a high degree of culture and civilization. They may have a large and industrious population, an advanced economic structure, great natural resources and extensive territories. Yet, even so, in isolation from the rest of the world they are quite incapable of finding an adequate solution to their major problems. The nations, therefore, must work with each other for their mutual development and perfection. They can help themselves only in so far as they succeed in helping one another. That is why international understanding and co-operation are so necessary.
Yet although individuals and nations are becoming more and more convinced of this twofold necessity, it would seem that men in general, and particularly those with high responsibility in public life, are showing themselves quite incapable of achieving it. The root of such inability is not to be sought in scientific, technical or economic reasons, but in the absense of mutual trust. Men, and consequently States, are in mortal fear of each other. Each fears that the other harbors plans of conquest and is only waiting for a favorable moment to put these plans into effect. Hence each organizes its own defense and builds up munitions of war as a deterrent against the would-be aggressor.