This article by George Weigel looks at the 1983 pastoral letter of the US Bishops, The Challenge of Peace in relation to what actually happened.
An excerpt:
“The farther the 1980s recede into the historical rear-view mirror, the less The Challenge of Peace looks like an insightful analysis of the political dynamics of that dramatic decade. It is now clear that disarmament -- not the arms control promoted by the bishops' letter, but real disarmament -- only took place after a human rights revolution had brought down the communist regimes of central and eastern Europe. The bishops' tacit argument that nuclear weapons issues could be factored out of the larger political context of the Cold War turned out to be quite wrong. There was a path to the end of the deterrence system and to genuine nuclear disarmament: it was victory over the Soviet Union. To suggest that TCOP missed this is, to put it gently, an understatement.
“The bishops' pastoral has left certain intellectual residues in the American Catholic mind; but it's hard to argue that these residues have had a positive effect on Catholic thought about war and peace. Go to most parishes today, listen to the way prayers for peace are framed in the General Intercessions, and you will hear a faithful echo of TCOP's failure to clarify the distinctions-in-kind among the peace of the Kingdom of God, the peace of a secure personal relationship with the Lord, and the peace of rightly-ordered political community (which is the only peace that politics can produce)”
Weigel—biographer of Pope John Paul II with the seminal Witness to Hope—explores this area at much more depth in his new book, Against the Grain: Christianity and Democracy, War and Peace, and one area he examines at some length is the just war doctrine of the Church, and here is an excerpt:
“The classic tradition, to repeat, begins with the presumption—better, the moral judgment—that rightly constituted public authority is under a strict moral obligation to defend the security of those for whom it has assumed responsibility, even if this puts the magistrate’s own life in jeopardy. That moral truth helps clarify one reason why Thomas Aquinas locates his discussion of bellum justum within the treatise on charity in the Summa Theologiae. That moral truth is why the late Paul Ramsey, who revived Protestant just war thinking in America after World War II, described the just war tradition as an explication of the public implications of the Great Commandment of love-of-neighbor (even as he argued that the commandment sets limits to the use of armed force).” (p. 209)
Thomas Aquinas also includes his support for capital punishment—another crucial state obligation stemming from the responsibility to protect—within the treatise on charity in the Summa Theologiae. (Article 6, Reply to Objection 2)