I believe it accelerated in the 60s. The late 60s with free love, drugs, counter-culture, radical liberalism, and the rejection of established values was actually born prior to its outbreak.
In the same way as "beatniks" preceded "hippies", in theology, the explosion of theological liberalism was certainly helped by the media's attack on our values-based American culture, but it was preceded by the slow erosion of our theology in our education centers. Depending on which voice you listen to, the major impact seems to have come from the European (German?) historical-critical directions taken by such stars as Rudolf Bultmann and Heidegger.
Their focus was "demythologizing" scripture. By that, they meant basically that you had to purge anything "miraculous-sounding" from scripture before you studied it. And this was after you'd already purged any scripture they felt really was illegitimate. ...
The Christianity Primer: Two Thousand Years of Amazing Grace – The History, Development, and Meaning of the Christian Religion, by Paul F.M. Zahl, © 2005
Rev. Dr. Zahl (now aged 61) is an ordained (Episcopal) orthodox Christian theologian and prolific writer. He served for almost a decade (ending in 2004) as the dean of the Episcopal Cathedral Church of the Advent in Birmingham, AL. He left in 2004 to become president of the Trinity School for Ministry (Episcopal) (the only orthodox seminary of the 11 TEC seminaries) outside of Pittsburg, PA. In 2007 he accepted the call to be rector to All Saints Church in Chevy Chase, MD.
"Chapter XX The Nineteenth Century: Modernism, Science, and the Bible"
p. 281-2 LIBERAL CATHOLICSM
… The 2nd reaction to the rise of modernism, science, and biblical criticism came from intellectuals and artists in England, America, and Scandinavia who came to embrace a philosophy referred to as romanticism. In the area of religion, romanticism manifests itself in the school of thought known as liberal catholicism. Liberal catholicism is not part of the Roman Catholic Church but is a specific version of Christianity that actually grew in liturgical Protestant churches such as the Anglican and Lutheran.
Liberal Catholicism is the dominant ethos of Anglicans in England and America today. It has a strong resonance with movements in the wider culture regarding homosexuality, pluralism and freedom of expression, yet with taste. We sometimes say that American Episcopalians will perform same-sex marriages, but not during Lent!
Liberal Catholicism combines dignified and beautiful worship with a sense of history and continuity and with modern ideas of science, the Bible, and progress. Rowan Williams, the 104th archbishop of Canterbury, is a liberal catholic, as is the current (2005) presiding bishop of the American Episcopal Church (Frank Griswold, now retired at age 74). The same is true of high church German Lutherans, a large minority of American Lutherans (mostly the ELCA) and the majority of Swedish Lutherans.
Liberal catholicism has become an influential species of romanticism. It is quite opposed to traditional Anglo-Catholicism and is extremely influential among mainstream Protestant Christians today.
p. 289 The Failure of the Ecumenical Movement … The ecumenical movement – the bringing together of Christians of all churches into common cause and unity – came and went. Beginning after WWI as a Protestant movement … it peaked with the founding of the World Council of Churches in 1948 (3 years after the founding of the United Nations). The Roman Catholics never joined, but the Orthodox churches did. The continuing failure to involve the Roman Catholic Church, the decline of liberal Protestantism in numbers and money, and the rise of unecumenical evangelical Protestantism and Pentecostalism in the southern hemisphere were realities too substantial for the ecumenical movement to overcome. Ecumenical unity among the churches will have to wait for another day.
Chapter XXI The Twentieth Century: The Challenge of Three Formidable Problems
p. 295 JUDAISMS ENDURING NO
… Judaism’s enduring no (refusal to accept Jesus Christ as the Son of God/ messiah) has never changed. Judaism has been strengthened immeasurably by the identity-renewing fact of the Holocaust and its political consequence, the creation of the state of Israel (despite the fact that Jews in the United States are increasingly secularized). The Christian significance of Judaism’s no has been worked out in changed doctrine for the Roman Catholics and sapped confidence for the Protestants. Large sectors of Christianity have lost their nerve as a result of Judaism’s negation. …
p. 286 The Catholic Church altered its teaching
… As a result of awareness of the Holocaust, the Catholic Church actually altered its historic teaching concerning Jews. Instead of saying that Jews needed to become Christians to be saved, Pope John Paul II instead declared just after the turn of the (21st) century that Jews have their own way to God and their own covenant and that these are just as valid for Jews as the New Covenant is for Christians. he was able with the stroke of a pen to declare null and void a position that his predecessors had taken from the earliest times. …
p. 295 … I predict that the next 30 years will see Christians needing to work very hard to absorb the impact of Jewish perspectives without giving up their own souls. The Southern Baptists, who have not compromised in relation to “Jewish evangelism,” may in fact end up carrying the soul of Bible Christianity for the rest of the Protestant churches during this era of Christian insecurity concerning the Person of Christ.
Excellent summary which reflects what we are all seeing and discussing.
http://www.victorhanson.com/articles/thornton101412.html
One Nation, Under God?
by Bruce Thornton
October 14, 2012
I haven't looked at it this way, more seeing that the mainline denominations went so far away from conservative values that Catholicism and evangelicals couldn't conceive "uniting" with them in reality
the Nazis forced even Jews who had become assimilated into other nationalities to be regarded as Jews alone. This, horrible, unforgiveable offense enhanced and boosted Jewish identity as you correctly pointed out