2. 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. The result is a vast expenditure of human energy and natural resources on projects which are disruptive of human society rather than beneficial to it; while a growing uneasiness gnaws at men's hearts and makes them less responsive to the call of nobler enterprises. The root cause of so much mistrust is the presence of ideological differences between nations, and more especially between their rulers. There are some indeed who go so far as to deny the existence of a moral order which is transcendent, absolute, universal ant equally binding upon all. And where the same law of justice is not adhered to by all, men cannot hope to come to open and full agreement on vital issues. (Papal Encyclical, Mater et Magistra, 15 May 1961).