Gaudium et Spes 81 continues on war, peace, and related issues. First, while the issue of MAD (mutually assured destruction) may be in the past, the principle of nations arming themselves while needs within the borders (and outside) go unmet is not morally tenable. We congratulate ourselves in the West for having won the Cold War, but we were quite close at times to stepping off the precipice into nuclear dark ages.
To be sure, scientific weapons are not amassed solely for use in war. Since the defensive strength of any nation is considered to be dependent upon its capacity for immediate retaliation, this accumulation of arms, which increases each year, likewise serves, in a way heretofore unknown, as deterrent to possible enemy attack. Many regard this procedure as the most effective way by which peace of a sort can be maintained between nations at the present time.
Whatever be the facts about this method of deterrence, (people) should be convinced that the arms race in which an already considerable number of countries are engaged is not a safe way to preserve a steady peace, nor is the so-called balance resulting from this race a sure and authentic peace. Rather than being eliminated thereby, the causes of war are in danger of being gradually aggravated. While extravagant sums are being spent for the furnishing of ever new weapons, an adequate remedy cannot be provided for the multiple miseries afflicting the whole modern world. Disagreements between nations are not really and radically healed; on the contrary, they spread the infection to other parts of the earth. New approaches based on reformed attitudes must be taken to remove this trap and to emancipate the world from its crushing anxiety through the restoration of genuine peace.
We might not have escaped nuclear ruin, though it appears our nation may be the only one immune from complete destruction. If the “interlude” spoken of below does not inspire us, it may well take a calamity to steer our priorities away from war and violence. God grant it does not come to pass.
Therefore, we say it again: the arms race is an utterly treacherous trap for humanity, and one which ensnares the poor to an intolerable degree. It is much to be feared that if this race persists, it will eventually spawn all the lethal ruin whose path it is now making ready. Warned by the calamities which the human race has made possible, let us make use of the interlude granted us from above and for which we are thankful to become more conscious of our own responsibility and to find means for resolving our disputes in a manner more worthy of man. Divine Providence urgently demands of us that we free ourselves from the age-old slavery of war. If we refuse to make this effort, we do not know where we will be led by the evil road we have set upon.
So the council gives believers a “clear duty.”
It is our clear duty, therefore, to strain every muscle in working for the time when all war can be completely outlawed by international consent. This goal undoubtedly requires the establishment of some universal public authority acknowledged as such by all and endowed with the power to safeguard on the behalf of all, security, regard for justice, and respect for rights. But before this hoped for authority can be set up, the highest existing international centers must devote themselves vigorously to the pursuit of better means for obtaining common security. Since peace must be born of mutual trust between nations and not be imposed on them through a fear of the available weapons, everyone must labor to put an end at last to the arms race, and to make a true beginning of disarmament, not unilaterally indeed, but proceeding at an equal pace according to agreement, and backed up by true and workable safeguards.(3. Cf. John XXIII, encyclical letter Pacem in Terris, where reduction of arms is mentioned: AAS 55 (1963), p. 287.)