Truth further demands an attitude of unruffled impartiality in the use of the many aids to the promotion and spread of mutual understanding between nations which modern scientific progress has made available. This does not mean that people should be prevented from drawing particular attention to the virtues of their own way of life, but it does mean the utter rejection of ways of disseminating information which violate the principles of truth and justice, and injure the reputation of another nation. 55Cf. Pius XII's broadcast message, Christmas 1940, AAS 33 (1941) 5-14.
Relations between States must furthermore be regulated by justice. This necessitates both the recognition of their mutual rights, and, at the same time, the fulfilment of their respective duties.
States have the right to existence, to self development, and to the means necessary to achieve this. They have the right to play the leading part in the process of their own development, and the right to their good name and due honors. Consequently, States are likewise in duty bound to safeguard all such rights effectively, and to avoid any action that could violate them. And just as individual men may not pursue their own private interests in a way that is unfair and detrimental to others, so too it would be criminal in a State to aim at improving itself by the use of methods which involve other nations in injury and unjust oppression. There is a saying of St. Augustine which has particular relevance in this context: "Take away justice, and what are kingdoms but mighty bands of robbers "56De civitate Dei, lib. IV, c. 4; PL 41. 115; cf. Pius XII's broadcast message, Christmas 1939, AAS 32 (1940) 5-13.