Is it easy to apply Christian moral principles in the world? Pope John thinks not:
154. In this connection We think it opportune to point out how difficult it is to understand clearly the relation between the objective requirements of justice and concrete situations; to define, that is, correctly to what degree and in what form doctrinal principles and directives must be applied in the given state of human society.
It wasn’t easier in 1963 than in years prior. It’s not any easier fifty years later.
155. The definition of these degrees and forms is all the more difficult in an age such as ours, driven forward by a fever of activity. And yet this is the age in which each one of us is required to make (their) own contribution to the universal common good. Daily is borne in on us the need to make the reality of social life conform better to the requirements of justice. Hence Our (daughters and) sons have every reason for not thinking that they can relax their efforts and be satisfied with what they have already achieved.
156. What has so far been achieved is insufficient compared with what needs to be done; all (people) must realize that. Every day provides a more important, a more fitting enterprise to which they must turn their hands—industry, trade unions, professional organizations, insurance, cultural institutions, the law, politics, medical and recreational facilities, and other such activities. The age in which we live needs all these things. It is an age in which (people), having discovered the atom and achieved the breakthrough into outer space, are now exploring other avenues, leading to almost limitless horizons.
Aware we often have no easy answers, my sense is that we really need a more positive element in the application of morality. What I mean is that believers applying the virtues. (Pick any New Testament list, blue highlighted here.) Avoiding the vices. Living those virtues publicly, openly, positively, and with joy. And in a difficult circumstance, we take our time.