Not all moral issues have the same moral weight as abortion and euthanasia. There may be legitimate diversity of opinion even among Catholics about waging war and applying the death penalty, but not... with regard to abortion and euthanasia.
While the Church exhorts civil authorities to seek peace, not war, and to exercise discretion and mercy in imposing punishment on criminals, it may still be permissible to take up arms to repel an aggressor or to have recourse to capital punishment. There may be a legitimate diversity of opinion even among Catholics about waging war and applying the death penalty, but not however with regard to abortion and euthanasia.
In a nuclear war there would be no victors, only victims. The truth of peace require that all-whether those governments which openly or secretly possess nuclear arms, or those planning to acquire them- agree to change their course by clear and firm decision and strive for a progressive and concerted nuclear disarmament. The resources which would be saved could then be employed in projects of development capable of benefiting all their people, especially the poor.
The destruction of the environment, its improper or selfish use, and the violent hoarding of the Earth's resources cause grievances, conflicts and wars, precisely because they are the consequences of an inhumane concept of development.
In a nuclear war there would be no victors, only victims. The truth of peace requires that all ... strive for a progressive and concerted nuclear disarmament.
