It is interesting that the only support for Vatican II is an obscure political letter. On the contrary, there are many papal and saintly quotes throughout Church history that are very clear that Islam is a diabolical sect (ie. worship Satan), that the Muslims are faithless, and that Islam displeases the divine majesty, etc., etc., etc.
What’s disturbing, is that those who quote Pope St. Gregory VII deliberately ignore the fact that at the time he wrote this letter, he was under duress; he was seeking the release of Catholic hostages held by the muslim savages.
“On the contrary, there are many papal and saintly quotes throughout Church history that are very clear that Islam is a diabolical sect (ie. worship Satan)...”
Actually, I don’t think any of the quotes you linked to say Muslims worship the Devil - although I freely admit I read only the comments in bold. A “diabolical sect” is one started by the Devil or oriented to serving his purposes. It’s purpose is not necessarily to directly worship the Devil, however, but to subtract from the Body of Christ and oppose it as a counterfeit. The very use of the word “sect” helps make that clear. That’s why Islam is so successful as an opponent of Christianity. It kept many of the words and ideas of Judaism and Christianity but it denies the very essence of Christian theology - the existence of the Trinity .