More optimism about the Church’s past success with modern day efforts in mission lands:
6. The present instruction has different situations in view. There are in the first place those countries which do not have a Christian tradition or where the Gospel has been proclaimed in modern times by missionaries who brought the Roman rite with them. It is now more evident that “coming into contact with different cultures, the church must welcome all that can be reconciled with the Gospel in the tradition of a people to bring to it the riches of Christ and to be enriched in turn by the many different forms of wisdom of the nations of the earth.” (Discourse to Pontifical Council for Culture, 5)
7. The situation is different in the countries with a long-standing Western Christian tradition, where the culture has already been penetrated for a long time by the faith and the liturgy expressed in the Roman rite. That has helped the welcome given to liturgical reform in these countries, and the measures of adaptation envisaged in the liturgical books were considered, on the whole, sufficient to allow for legitimate local diversity (cf. below Nos. 53-61). In some countries, however, where several cultures coexist, especially as a result of immigration, it is necessary to take account of the particular problems which this poses (cf. below No. 49).
It is generally conceded that the Americas would be areas where the mainstream culture has been long “penetrated” by Christian faith and Catholic liturgy. Therefore, the options given in the rites are considered “sufficient” for us.
On the other hand, the world’s people are mobile to a degree not envisioned by past centuries in the Church, or perhaps even at Vatican II. At any rate, we are not likely to see one continent overwhelm another in terms of immigration ever again. So the Church must deal with minority cultures arriving in Christian lands and assess if the mainstream culture is sufficient to allow for an effective evangelization of non-believers. As the note above suggests, VL 49 will address some of this issue.