DISARMAMENT. - The common good, the essential end of the State, imposes on public authority the duty of providing for internal order and of defending against possible external aggressions the rights of the society over whose life it presides. It therefore makes legitimate the maintenance of an organized force at the disposal of the executive power, in order to suppress the causes of internal disorder and to repel aggressions from outside. The size, however, of such public force must be strictly proportionate to the demands of the end that is intended to be achieved, and therefore kept within reasonable limits, so that on the other hand it does not come to prejudice other important elements of the common good. Catholic doctrine consequently, just as it does not judge war illegitimate in principle, provided it meets certain conditions, so it declares illegitimate neither the profession of arms nor a corresponding armament, provided it does not exceed the necessities of defense.
The implementation of d. therefore depends on the greater or lesser security upon which a nation can count, both internally and externally. D. and security are two problems intimately connected and inseparable. It is also clear how d. can only reach a certain degree: since the State always needs an armed force, if only for internal defense, d. will in every supposition be partial. Rather, than of d. one should more properly speak of reduction and limitation of armaments, and the limits within which these should be contained should depend on the principle that the purpose of the armed forces is essentially defensive, their justification deriving from the necessity of defense both of internal order and of law in the international field.

The forgetting of these norms has been the cause of the arms race that has occurred from the 17th century onward. The policy of equilibrium, founded solely on the relation of forces, has forced nations to stand perpetually on a war footing, since an arrangement resting on so unstable a foundation could give way from one moment to the next and give rise to an armed conflict. To foment the process was added the atmosphere of suspicions about the intentions of others, since one does not arm in order then to keep the powder dry in the powder magazines, and the consequent distrust of fidelity to international stipulations. A purely mechanical order, constructed without the support of any moral and juridical principle valid before the force of the powers, cannot generate security. Legal positivism has helped to feed the psychosis of arms. If a State, according to international law as interpreted by the positivists and accepted for convenience by politicians, possesses full freedom to wage war for any reason, there remains to the other States nothing but to take precautions, entrusting their own security to force and not to law.
All these causes and still others led States to adopt the formula of the armed nation, maintaining standing armies, introducing compulsory conscription and progressively increasing their effectives, in a dizzying contest of expenditures harmful to the general economy of the country, whose resources were in good part swallowed up by military budgets.
The voice of the Church has not failed to warn peoples of the dangers of such a ruinous policy. Leo XIII, in the apostolic letter Pervenuti all'anno vigesimo quinto, of 9 March 1902, deplored "the fatal criteria that consecrate material forces as almost the supreme law of the world: whence the progressive and boundless increase of warlike preparations; that is, that armed peace comparable in many respects to the most disastrous effects of war." Pius X, in a letter sent on 11 June 1911 to the apostolic delegate of the United States, praised the initiative of the Carnegie endowment in favor of d., necessary, he said, "all the more in this time when the numerical importance of armies, the power of the instruments of war, and military science so greatly advanced, allow one to glimpse the possibility of wars that should inspire lively fear even in the most powerful princes." Well known are the proposals of Benedict XV to the belligerent peoples of the First World War, made public on 1 Aug. 1917. For the attainment of peace, among other things the Pope recommended "a just agreement of all in the simultaneous and reciprocal diminution of armaments, according to norms and guarantees to be established in the measure necessary and sufficient for the maintenance of public order in the individual States." In the same sense Pius XI expressed himself in the encyclical Ubi Arcano Dei of 23 Dec. 1922. The Church has, therefore, made the cause of d. its own.
Attempts to reach an agreement on this subject have not been lacking in the history of international relations. The aspiration to diminish the means of offense for the benefit of humanity has always been alive among peoples and among certain statesmen, but it has never succeeded in taking concrete form. In 1814, while the Treaty of Paris was being negotiated, Talleyrand proposed to the victorious powers that they seriously examine the possibility of reducing armies in peacetime. The untimely proposal was not accepted, because France, exhausted by twenty years of war, did not then enjoy sufficient prestige. In 1831 the same France took the initiative of an equal proposal, to which Prince Metternich objected that the return of armies to a peacetime footing could only be a consequence of the security and confidence achieved in the good will of States to respect the commitments undertaken.
More serious was the attempt of Tsar Nicholas II, who took up the idea of a general reduction of armaments, inviting States in 1898 to a conference to discuss the question. The small nations responded favorably to the invitation, which was received coldly by the great powers, which at the Hague conference of 1899 definitively caused the proposal to fail, notwithstanding that Russia had limited the original program to the modest proportion of a general commitment not to increase armaments for the space of a few years. These repeated fruitless attempts show how impossible it is to resolve the problem of material d. without a prior moral d. and the transformation of that egoistic mentality, solely intent on the triumph of the particular interests of each nation.
The persistence of such a mental attitude and the never abandoned hegemonic aims of the great powers rendered vain the efforts more recently made by the League of Nations, to reach a collective agreement on the reduction of armaments. At the end of the First World War, the States, instructed by recent experience, showed themselves more disposed to accept, with art. 8 of the Covenant, the principle that was a requirement of peace: to reduce national armaments "to the lowest point compatible with national security and the execution of international obligations imposed by common action," entrusting the Council with preparing the plans to be submitted afterward to the approval of the governments. Meanwhile they undertook to exchange all information relating to the degree of their armaments and to military, naval and air programs. The prospects of a d. were confirmed by the preamble of part 5 of the Treaty of Versailles (1919), in which it was said that Germany undertook to observe strictly the military, naval and air clauses imposed on it, "with a view to making possible the preparation of a general limitation of the armaments of all nations."
Twelve years, however, had to pass before the plenary Conference for the reduction and limitation of armaments was convened. This Conference, inaugurated in 1932, carried on its work amid insuperable difficulties raised by the conflicting policies of the powers, had to be suspended in 1933 because of the withdrawal of Germany, which was already secretly arming, and closed its doors with nothing accomplished. The arms race began again unchecked until the outbreak of the Second World War, at the end of which the victorious powers, who drafted the Charter of the United Nations, granted to disarmament only a few passing mentions, as a subject on which the attention of the General Assembly and of the Military Staff Committee might dwell (Arts. 11 and 47), without entering into any formal commitment to carry it out.
The need to arrive at a reduction of armaments nevertheless remains pressing. Pius XII insisted on it repeatedly during the years of the last conflict. In the Christmas message of 1939, he warned that "conclusions of peace which did not attribute fundamental importance to a mutually agreed, organic, progressive disarmament, both in the practical and in the spiritual order, and did not strive to carry it out loyally, would reveal, sooner or later, their inconsistency and lack of vitality." He returned to the same subject again at Christmas 1941.
The attainment of this high goal will not be possible without the prior realization of certain prerequisites. Moral disarmament, which has been mentioned, must be accompanied by a reborn sense of the sacred character of law, with the abandonment of the fatal principle that force replaces it or produces it; by a consequent mutual trust among States, made secure that their rights will not be violated with impunity; by the establishment of an efficient international body, to which the defense of small and great nations and the control of their armaments would be entrusted. Difficult certainly is the reaching of these goals, but the evolution of international law and institutions must strive toward them with constancy, in order to free peoples from the specter of war and from the unbearable burden of unproductive expenditures, which devour national resources and impoverish the economy of peoples.
Bibliography6 works
Antonio Messineo