The fact that heresies and heretics exists in no way destroys or diminishes the doctrinal unity of the Church. In fact, it amplifies the truth.
The Church must proclaim and defend the truth. Jesus predicted that the truth would divide families and that the apostles would need swords. There is no evidence of the Roman armies destroying other Churches at the behest of the Church. In fact, doctrinal disputes were taken up at Church councils, not with swords. Heretics were excommunicated, not executed. How do you suppose we know of the heresies of Arianism, Donatism, Docetism, etc.?
Throughout Christian history the Church has been the pillar and foundation of the truth. Outside the Church you find multiple contradictory doctrines.
The Catholic church defines a heretic as anyone who disagrees with the Catholic church. Since that is the definition, it is not surprising that the Catholic church can maintain that what is says is true, and everyone else is false.
I agree that there is no definite evidence of the Catholic church taking armies to destroy the church. Even the evidence of Hypatia is questioned by some (the bishop ordered a yong woman skinned alive because she had a government post without being baptized). The Inquisition's condemnation of Galileo is an established fact. That the Inquisition put people to death for disagreeing with Rome is an established fact.
It is a circular argument that the church teaches the truth, and therefore anyone else is wrong. You cannot prove independently that what the church teaches is true.
WHen Peter used his sword, Jesus healed the ear or the high-priests servant. Who is healing the thousands of sodomized altar boys, protected by bishops' coverups?
I covered the circular argument of cntradictory doctrine above.
You are not answering any of my evidence. You just say the same thing over and over: "My church is right. Therefore you are wrong. Since you cannot be correct, I need not answer your proofs to the contrary." You prove you are right by saying you agree with your own books. You prove your books are not altered by saying you are right, so they could not have been altered. You say any history that does not agree is made up because the books you made up disagree.
Again, account for the false apostles, account for Hypatia, account for the churches that are not in communion with the Pope from the beginning. Account for Barnabas being an apostle. Account for the witchcraft in catholic cemeteries. Account for Acts 7 saying the church existed at Sinai. Account for the continuing Irish/British religious tension. You have not answered one single fact I have brought up. You just keep going in self-referential circles.