It is believed that the true Third Secret of Fatima was a warning regarding the errors of Vatican II, as Our Lady wished it to be revealed in 1960 (when Vatican II preparations were being made) as it would be more clear then. The error of Vatican II was in the watering down of the Catholic faith to better appeal to the Protestant churches and in rebellion against the authority of the Pope, the Bishops wanting to have equal power with the Pope. The first Council, recorded in the Bible, showed discussion amongst the Apostles about requirements for gentile converts, with Peter (the first Pope) making the final decision. Vatican II made ambiguous statements that were left up to the individual Bishops to decide on the particulars, in essence giving them little kingdoms within Christianity. That is why there is so much disunity within the Catholic Church today. As there are thousands of Protestant denominations today, so there are slightly variant Catholic diocese. The change was a very human attempt to bring "peace" to mankind via an ecumenical utopia.
The effect of Vatican II is being seen as confusion and compromise within the Catholic church, with grappling for control by hierarchy and for liberal latitude by laity. Caring for those within the Protestant faith should not destroy the only Christian church actually founded by Jesus himself. The Catholic faith preserved the Bible (monks copying it for centuries), and have the full Bible (Martin Luther threw out seven books because he did not like the dogmas they supported - like purgatory). The Catholic faith also has the traditional teaching of the Apostles (called Apostolic Tradition), mainly the seven sacraments (baptism, the Eucharist, confession, confirmation, marriage, holy orders for priests, sacrament of the sick), and what they taught about Mary and the scriptures. The Bible says Jesus taught his Apostles in private, and the Archbishops and the Pope are their successors today and follow the Apostolic Tradition.
Vatican II did not change the basic dogmas of the Catholic faith or the Apostolic Tradition, nor did it elevate Islam. Islam came six hundred years after Jesus, and Mohammad sought to legitimize and make superior Abraham's first son, Ishmael, as the heir to the covenant, and establish Mohammad as the main prophet of the covenant with Ishmael's line. Mohammad denied that God chose the Jews to preserve the true faith and the true covenant with God. Mohammad denied that Jesus was the Jewish Messiah, the Paschal lamb and the New Covenant promised in the Old Testament. Instead, Mohammad rewrote the Bible, including what he knew of the Gnostic Gospels (basically novels that the Council of Trent declared were not part of the Bible in order to dispel any confusion), in order to make himself (Mohammad) the main character. Islam is blatantly anti-Christ, as the golden dome on the Temple Mount inscription ("God has no son") declares. The Catholic church, including Vatican II, never formally recognized Islam as anything but diabolical heresy, but only reminded Catholics to love Muslims anyway and to remember that they might be in good faith even in their error.
