The End of the "Interlude" – Nuclear Deterrence in the Light of Roman Catholic Social Teaching

Pope Francis’ statements on banning nuclear weapons have attracted much attention, but they can be placed in the long tradition of peace ethics in the Church’s teachings. The Second World War and the development of weapons of mass destruction intensified open skepticism toward armaments and military conflict resolution. But this did not bring about a fundamental rejection of the bellum iustum doctrine as an ethical framework for assessing the legitimacy of warfare. It was the Second Vatican Council that pointed out that the destructive power of nuclear weapons puts them beyond any permissible defense. It coined the idea of an “interlude granted us from above” – in view of the threat of extinction, the time remaining for humanity to find an appropriate way of resolving conflicts. In their pastoral letter “The Challenge of Peace”, the U.S. bishops did not declare nuclear deterrence to be completely unacceptable. But they did indissolubly link its temporary acceptance to conditions such as serious arms control and disarmament efforts. Thus we find indications of the Vatican’s current position – removing the distinction between (conditionally) permitted possession of nuclear weapons and their prohibited use – at an early stage. Long-held ethical doubts about a policy that establishes “peace” only on the basis of the threat of mutual annihilation are compounded by the judgment that the will to disarmament is not discernible, and therefore an essential condition for toleration is not met. The German Commission for Justice and Peace has also adopted this line of argument, declaring in 2019 that banning nuclear weapons is the starting point for the desired disarmament process. It therefore sought to draw a line under abusive interpretations of the “interlude”. The Catholic Church’s commitment to a complete ban on and abolition of nuclear weapons is perceived as turnaround, but in reality it is a stringent continuation of its social teaching. Regardless of religious affiliation, this teaching appeals to our human sense of morality as the Church seeks to gain broad support for a gradual turning away from nuclear deterrence.