I have read quite a few comments from Roman Catholic Apologetics regarding the "25,000 groups" of "Protestants", who can’t agree among ourselves. Even though I have attempted to explain to several of my Roman Catholic friends that Baptists and Pentecostals are not Protestants, since we aren’t protesting anything, they insist that we are.
Let’s take a look at the "unity" in the Universal Church of Roman Catholicism. In this morass there are:
1. born-again Catholics who received Jesus as their Saviour in spite of the definition of salvation by the Roman Catholic magisterium. They entrusted their lives to Jesus and trust in Him alone for salvation. These Catholics share many of our basic beliefs in the Scriptures, the Resurrection, the virgin birth of Jesus and the other basic tenets of the Christian faith.
2. There are Catholics still rebelling against Vatican II who ignore the Tridentine prohibition and attend masses said in Latin, e.g. Bishop LaFebvre.
3. We have some rather "liberal" Roman Catholics such as an active nun who held a public office in my state and espoused abortion as a woman’s right in spite of her Church’s official condemnation of abortion. She is not alone in her views. She represents quite a few challenging the belief system of their Church.
4. There are Liberation theologians and their adherents who preach the gospel with an AK-47. For them it isn’t the truth that will make you free but rather the barrel of a gun. Some such adherents are active clerics in the Jesuits and the Maryknoll order. Some assisted the Ortegas in taking over Nicaragua and a couple are even in the Sandanista government as officials. This movement has been warned severely by the present pope several times - to no avail. Maybe he didn’t do it “ex cathedra”.
5. There are very conservative Catholics such as IN HOC SIGNO VINCES (The battle cry of Constantine - In this sign, conquer). These people are on the internet and don’t waste time talking to us as “separated” brethren. They just tell us we are heretics on our way to hell because of their man-made doctrine Extra Ecclesium Nulla Salus - Outside the Church (The Roman Catholic Church), there is no salvation. This great doctrine was handed down from the Council of Trent and has never been officially denied or renounced since Vatican II. The IHSV people can barely tolerate this present pope whom they see as leading them into a disastrous ecumenism. (I might agree with that last point myself).
6. In the Keys of this Blood by Malachi Martin (investigative journalist, ex-Jesuit theologian who contributed greatly to Vatican II and a personal confidante of Pope John Paul II), Martin writes regarding the serious concerns that this present pope has about the future of the Roman Catholic Church and the condition of a majority of his bishops who no longer accept as true doctrine the physical Resurrection of Jesus, the infallibility of the Holy Scriptures, the virgin birth of Jesus and the divinity of Jesus. Many of these men hold the views of Hans Kung, a renegade theologian in the Roman Church who actively teaches against these basic beliefs of Christianity.
7. Although I have read how the Roman Catholic Church bitterly denounced William Tyndale as a heretic and murdered him for translating the Bible into the language of the common people, I have never seen a pope excommunicate a member of the Mafia. Nor have I seen the Church of Rome reprimand a well-known psychic whose occult prophecies are reported annually in the yellow journals that populate our food stores. She is a daily communicant of the eucharist in her local parish.
Universal Church??? I don’t think so. I think this is an institution in search of a meaning.
These articles are all written by Roman Catholics
Ecumenism & the United Communities of Spirit Article on Christianity Compromising everything for the sake of unity by The Rev. Thomas A. Baima, S.T.L. Catholic Priest, Director of the Office for Ecumenical and Interreligious Affairs of the Archdiocese of Chicago, and Trustee of The Council for a Parliament of the World's Religions
"True Roman Catholics" and their writings
101 Heresies of Anti-Pope John Paul II
Baltimore Catechism of 1941 - True Catholic Catechism
Heresies of Vatican II
An Open Letter to

Catholics Letter and articles from Archbishop Marcel Lefebvre
The Catholic Origin of Liberation Theology
Catholic Liberation Theology
In the United States, Maryknoll militancy is manifested in their media productions, including films glorifying the Sandinista regime in Nicaragua, and books published by Maryknoll’s Orbis Books. Liberation Theology - preaching the gospel through the barrel of a gun
Roman Catholic Supporters of Abortion Rights
Catholics opposing the "Anti-Church" of Vatican II
With the Great Schism engineered by the Roman Modernist wing of Liberal Protestant heretics, under the auspices of Angelus Joseph Roncalli, there gradually arose various groups in opposition and to defend, preserve and ensure the perpetuation of the True Church. These groups together comprise the Catholic Resistance. The Resistance can be grouped into n broad schools of thought - Cassicanists, Sede-Vacantists, Orthopapists; excluding those who strayed into heresy or who compromised with the Roncallite Antichurch.
The Roman Catholic Faithful
Lay Catholics attempting to rid themselves of perverse and homosexual clergy
The Catholic Counter-Reformation of the 20th Century speaks out against apostasy in their Catholic Church
Papal Rebuke by alleged "Queen of Heaven"