If one recalls the time frame from which Radio Replies emerged, it can explain some of the frankness and lack of tact in the nature of the responses provided.
It was during this timeframe that a considerable amount of anti-Catholic rhetoric came to the forefront, particularly in this country. Much of this developed during the Presidential campaign of Al Smith in 1928, but had its roots in the publication of Alexander Hislop's The Two Babylons, originally published in book form in 1919 and also published in pamphlet form in 1853.
While in Britain (and consequently Australia), the other fellow would surely have experienced the effects of the Popery Act, the Act of Settlement, the Disenfranchising Act, the Ecclesiastical Titles Act, and many others since the reformation (that basically boiled down to saying, "We won't kill you if you just be good, quiet little Catholics"). Even the so-called Catholic Relief Acts (1778, 1791, 1829, 1851, 1871) still had huge barriers placed in the way.
And of course, they'd both remember the American Protective Association, "Guy Fawkes Days" (which included burning the Pontiff in effigy), the positions of the Whigs and Ultra-Torries, and so on.
A strong degree of "in your face" from people in the position of authoritativeness was required back in the 1930s, as there was a large contingent of the populations of both the US and the British Empire who were not at all shy about being "in your face" toward Catholics in the first place (in other words, a particularly contentious day on Free Republic would be considered a mild day in some circles back then). Sure, in polite, educated circles, contention was avoided (thus the little ditty about it not being polite to discuss religion in public, along with sex and politics), but it would be naive to assume that we all got along, or anything resembling that, back in the day.
Having said all of the above, reading the articles from the modern mindset and without the historical context that I tried to briefly summarize above, they make challenging reading, due to their bluntness.
The reader should also keep in mind that the official teaching of the Church takes a completely different tone, best summed up in the Catechism of the Catholic Church:
817 In fact, "in this one and only Church of God from its very beginnings there arose certain rifts, which the Apostle strongly censures as damnable. But in subsequent centuries much more serious dissensions appeared and large communities became separated from full communion with the Catholic Church - for which, often enough, men of both sides were to blame."269 The ruptures that wound the unity of Christ's Body - here we must distinguish heresy, apostasy, and schism270 - do not occur without human sin:Where there are sins, there are also divisions, schisms, heresies, and disputes. Where there is virtue, however, there also are harmony and unity, from which arise the one heart and one soul of all believers.271
818 "However, one cannot charge with the sin of the separation those who at present are born into these communities [that resulted from such separation] and in them are brought up in the faith of Christ, and the Catholic Church accepts them with respect and affection as brothers .... All who have been justified by faith in Baptism are incorporated into Christ; they therefore have a right to be called Christians, and with good reason are accepted as brothers in the Lord by the children of the Catholic Church."272
819 "Furthermore, many elements of sanctification and of truth"273 are found outside the visible confines of the Catholic Church: "the written Word of God; the life of grace; faith, hope, and charity, with the other interior gifts of the Holy Spirit, as well as visible elements."274 Christ's Spirit uses these Churches and ecclesial communities as means of salvation, whose power derives from the fullness of grace and truth that Christ has entrusted to the Catholic Church. All these blessings come from Christ and lead to him,275 and are in themselves calls to "Catholic unity."276
838 "The Church knows that she is joined in many ways to the baptized who are honored by the name of Christian, but do not profess the Catholic faith in its entirety or have not preserved unity or communion under the successor of Peter."322 Those "who believe in Christ and have been properly baptized are put in a certain, although imperfect, communion with the Catholic Church."323 With the Orthodox Churches, this communion is so profound "that it lacks little to attain the fullness that would permit a common celebration of the Lord's Eucharist."324
269 UR 3 § 1.
270 Cf. CIC, can. 751.
271 Origen, Hom. in Ezech. 9,1:PG 13,732.
272 UR 3 § 1.
273 LG 8 § 2.
274 UR 3 § 2; cf. LG 15.
275 Cf. UR 3.
276 Cf. LG 8.
322 LG 15.
323 UR 3.
324 Paul VI, Discourse, December 14, 1975; cf. UR 13-18.
Radio Replies Volume Two: Destiny of Man/Death
Radio Replies Volume Two: Immortality of Man's Soul & Pre-existence Denied
Radio Replies Volume Two: The Human Free Will
Radio Replies Volume Two: Determinism Absurd
Radio Replies Volume Two: Necessity of Religion
Radio Replies Volume Two: Salvation of the Soul
Radio Replies Volume Two: Voice of Science
Radio Replies Volume Two: Religious Racketeers
Radio Replies Volume Two: Divine Revelation
Radio Replies Volume Two: Gospels Historical
Radio Replies Volume Two: Missing Books of the Bible
Radio Replies Volume Two: The Bible Inspired
Radio Replies Volume Two: Biblical Account of Creation
Radio Replies Volume Two: New Testament Problems
Radio Replies Volume Two: Source of Christian Teaching
Radio Replies Volume Two: Jewish Rejecton of Christ
Radio Replies Volume Two: Christianity a New Religion
Radio Replies Volume Two: Rational Foundation for Belief
Radio Replies Volume Two: Causes of Unbelief
CONGREGATION FOR THE DOCTRINE OF THE FAITH
RESPONSES TO SOME QUESTIONS REGARDING CERTAIN ASPECTS OF THE DOCTRINE ON THE CHURCH
The Second Vatican Council, with its Dogmatic Constitution Lumen gentium, and its Decrees on Ecumenism (Unitatis redintegratio) and the Oriental Churches (Orientalium Ecclesiarum), has contributed in a decisive way to the renewal of Catholic ecclesiology. The Supreme Pontiffs have also contributed to this renewal by offering their own insights and orientations for praxis: Paul VI in his Encyclical Letter Ecclesiam suam (1964) and John Paul II in his Encyclical Letter Ut unum sint (1995).
The consequent duty of theologians to expound with greater clarity the diverse aspects of ecclesiology has resulted in a flowering of writing in this field. In fact it has become evident that this theme is a most fruitful one which, however, has also at times required clarification by way of precise definition and correction, for instance in the declaration Mysterium Ecclesiae (1973), the Letter addressed to the Bishops of the Catholic Church Communionis notio (1992), and the declaration Dominus Iesus (2000), all published by the Congregation for the Doctrine of the Faith.
The vastness of the subject matter and the novelty of many of the themes involved continue to provoke theological reflection. Among the many new contributions to the field, some are not immune from erroneous interpretation which in turn give rise to confusion and doubt. A number of these interpretations have been referred to the attention of the Congregation for the Doctrine of the Faith. Given the universality of Catholic doctrine on the Church, the Congregation wishes to respond to these questions by clarifying the authentic meaning of some ecclesiological expressions used by the magisterium which are open to misunderstanding in the theological debate.
RESPONSES TO THE QUESTIONS
Did the Second Vatican Council change the Catholic doctrine on the Church?
The Second Vatican Council neither changed nor intended to change this doctrine, rather it developed, deepened and more fully explained it.
This was exactly what John XXIII said at the beginning of the Council. Paul VI affirmed it and commented in the act of promulgating the Constitution Lumen gentium: There is no better comment to make than to say that this promulgation really changes nothing of the traditional doctrine. What Christ willed, we also will. What was, still is. What the Church has taught down through the centuries, we also teach. In simple terms that which was assumed, is now explicit; that which was uncertain, is now clarified; that which was meditated upon, discussed and sometimes argued over, is now put together in one clear formulation. The Bishops repeatedly expressed and fulfilled this intention.
What is the meaning of the affirmation that the Church of Christ subsists in the Catholic Church?
Christ established here on earth only one Church and instituted it as a visible and spiritual community, that from its beginning and throughout the centuries has always existed and will always exist, and in which alone are found all the elements that Christ himself instituted. This one Church of Christ, which we confess in the Creed as one, holy, catholic and apostolic [ ]. This Church, constituted and organised in this world as a society, subsists in the Catholic Church, governed by the successor of Peter and the Bishops in communion with him.
In number 8 of the Dogmatic Constitution Lumen gentium subsistence means this perduring, historical continuity and the permanence of all the elements instituted by Christ in the Catholic Church, in which the Church of Christ is concretely found on this earth.
It is possible, according to Catholic doctrine, to affirm correctly that the Church of Christ is present and operative in the churches and ecclesial Communities not yet fully in communion with the Catholic Church, on account of the elements of sanctification and truth that are present in them. Nevertheless, the word subsists can only be attributed to the Catholic Church alone precisely because it refers to the mark of unity that we profess in the symbols of the faith (I believe... in the one Church); and this one Church subsists in the Catholic Church.
Why was the expression subsists in adopted instead of the simple word is?
The use of this expression, which indicates the full identity of the Church of Christ with the Catholic Church, does not change the doctrine on the Church. Rather, it comes from and brings out more clearly the fact that there are numerous elements of sanctification and of truth which are found outside her structure, but which as gifts properly belonging to the Church of Christ, impel towards Catholic Unity.
It follows that these separated churches and Communities, though we believe they suffer from defects, are deprived neither of significance nor importance in the mystery of salvation. In fact the Spirit of Christ has not refrained from using them as instruments of salvation, whose value derives from that fullness of grace and of truth which has been entrusted to the Catholic Church.
Why does the Second Vatican Council use the term Church in reference to the oriental Churches separated from full communion with the Catholic Church?
The Council wanted to adopt the traditional use of the term. Because these Churches, although separated, have true sacraments and above all because of the apostolic succession the priesthood and the Eucharist, by means of which they remain linked to us by very close bonds, they merit the title of particular or local Churches, and are called sister Churches of the particular Catholic Churches.
It is through the celebration of the Eucharist of the Lord in each of these Churches that the Church of God is built up and grows in stature. However, since communion with the Catholic Church, the visible head of which is the Bishop of Rome and the Successor of Peter, is not some external complement to a particular Church but rather one of its internal constitutive principles, these venerable Christian communities lack something in their condition as particular churches.
On the other hand, because of the division between Christians, the fullness of universality, which is proper to the Church governed by the Successor of Peter and the Bishops in communion with him, is not fully realised in history.
Why do the texts of the Council and those of the Magisterium since the Council not use the title of Church with regard to those Christian Communities born out of the Reformation of the sixteenth century?
According to Catholic doctrine, these Communities do not enjoy apostolic succession in the sacrament of Orders, and are, therefore, deprived of a constitutive element of the Church. These ecclesial Communities which, specifically because of the absence of the sacramental priesthood, have not preserved the genuine and integral substance of the Eucharistic Mystery cannot, according to Catholic doctrine, be called Churches in the proper sense.
The Supreme Pontiff Benedict XVI, at the Audience granted to the undersigned Cardinal Prefect of the Congregation for the Doctrine of the Faith, ratified and confirmed these Responses, adopted in the Plenary Session of the Congregation, and ordered their publication.
Rome, from the Offices of the Congregation for the Doctrine of the Faith, June 29, 2007, the Solemnity of the Holy Apostles Peter and Paul.
William Cardinal Levada
Angelo Amato, S.D.B.
 John XXIII, Address of 11 October 1962: The Council wishes to transmit Catholic doctrine, whole and entire, without alteration or deviation To be sure, at the present time, it is necessary that Christian doctrine in its entirety, and with nothing taken away from it, is accepted with renewed enthusiasm, and serene and tranquil adherence it is necessary that the very same doctrine be understood more widely and more profoundly as all those who sincerely adhere to the Christian, Catholic and Apostolic faith strongly desire it is necessary that this certain and unchangeable doctrine, to which is owed the obedience of faith, be explored and expounded in the manner required by our times. For the deposit of faith itself, or the truths which are contained in our venerable doctrine, are one thing; another thing is the way in which they are expressed, with however the same meaning and signification: AAS 54  791-792
 Cf. Paul VI, Address of 29 September 1963: AAS 55  847-852.
 Paul VI, Address of 21 November 1964: AAS 56  1009-1010.
 The Council wished to express the identity of the Church of Christ with the Catholic Church. This is clear from the discussions on the decree Unitatis redintegratio. The Schema of the Decree was proposed on the floor of the Council on 23.9.1964 with a Relatio (Act Syn III/II 296-344). The Secretariat for the Unity of Christians responded on 10.11.1964 to the suggestions sent by Bishops in the months that followed (Act Syn III/VII 11-49). Herewith are quoted four texts from this Expensio modorum concerning this first response.
A) [In Nr. 1 (Prooemium) Schema Decreti: Act Syn III/II 296, 3-6]
Pag. 5, lin. 3-6: Videtur etiam Ecclesiam catholicam inter illas Communiones comprehendi, quod falsum esset. R(espondetur): Hic tantum factum, prout ab omnibus conspicitur, describendum est. Postea clare affirmatur solam Ecclesiam catholicam esse veram Ecclesiam Christi (Act Syn III/VII 12).
B) [In Caput I in genere: Act Syn III/II 297-301]
4 - Expressius dicatur unam solam esse veram Ecclesiam Christi; hanc esse Catholicam Apostolicam Romanam; omnes debere inquirere, ut eam cognoscant et ingrediantur ad salutem obtinendam...
R(espondetur): In toto textu sufficienter effertur, quod postulatur. Ex altera parte non est tacendum etiam in aliis communitatibus christianis inveniri veritates revelatas et elementa ecclesialia(Act Syn III/VII 15). Cf. also ibid pt. 5.
C) [In Caput I in genere: Act Syn III/II 296s]
5 - Clarius dicendum esset veram Ecclesiam esse solam Ecclesiam catholicam romanam... R(espondetur): Textus supponit doctrinam in constitutione De Ecclesia expositam, ut pag. 5, lin. 24-25 affirmatur (Act Syn III/VII 15). Thus the commission whose task it was to evaluate the responses to the Decree Unitatis redintegratio clearly expressed the identity of the Church of Christ with the Catholic Church and its unicity, and understood this doctrine to be founded in the Dogmatic Constitution Lumen gentium.
D) [In Nr. 2 Schema Decreti: Act Syn III/II 297s]
Pag. 6, lin. 1- 24: Clarius exprimatur unicitas Ecclesiae. Non sufficit inculcare, ut in textu fit, unitatem Ecclesiae. R(espondetur): a) Ex toto textu clare apparet identificatio Ecclesiae Christi cum Ecclesia catholica, quamvis, ut oportet, efferantur elementa ecclesialia aliarum communitatum.
Pag. 7, lin. 5: Ecclesia a successoribus Apostolorum cum Petri successore capite gubernata (cf. novum textum ad pag. 6, lin.33-34) explicite dicitur unicus Dei grex et lin. 13 una et unica Dei Ecclesia (Act Syn III/VII). The two expressions quoted are those of Unitatis redintegratio 2.5 e 3.1.
 Cf. Second Vatican Council, Dogmatic Constitution Lumen gentium, 8.1.
 Cf. Second Vatican Council, Decree Unitatis redintegratio, 3.2; 3.4; 3.5; 4.6.
 Second Vatican Council, Dogmatic Constitution, Lumen gentium, 8.2.
 Cf. Congregation for the Doctrine of the Faith, Declaration Mysterium Ecclesiae, 1.1: AAS 65  397; Declaration Dominus Iesus, 16.3: AAS 92 [2000-II] 757-758; Notification on the Book of Leonardo Boff, OFM, Church: Charism and Power: AAS 77  758-759.
 Cf. John Paul II, Encyclical Letter Ut unum sint, 11.3: AAS 87 [1995-II] 928.
 Cf. Second Vatican Council, Dogmatic Constitution Lumen gentium, 8.2.
 Second Vatican Council, Dogmatic Constitution Lumen gentium, 8.2.
 Second Vatican Council, Decree Unitatis redintegratio, 3.4.
 Second Vatican Council, Decree Unitatis redintegratio, 15.3; cf. Congregation for the Doctrine of the Faith, Letter Communionis notio, 17.2: AAS, 85 [1993-II] 848.
 Second Vatican Council, Decree Unitatis redintegratio, 14.1.
 Cf. Second Vatican Council, Decree Unitatis redintegratio, 14.1; John Paul II, Encyclical Letter Ut unum sint, 56 f: AAS 87 [1995-II] 954 ff.
 Second Vatican Council, Decree Unitatis redintegratio, 15.1.
 Cf. Congregation for the Doctrine of the Faith, Letter Communionis notio, 17.3: AAS 85 [1993-II] 849.
 Cf. Second Vatican Council, Decree Unitatis redintegratio, 22.3.
 Cf. Congregation for the Doctrine of the Faith, Declaration Dominus Iesus, 17.2: AAS 92 [2000-II] 758.