Yes, Muslims did start kicking Christians around. For one; https://en.wikipedia.org/wiki/Byzantine%E2%80%93Seljuk_wars#Origins
Sometimes they respected other religions, but sometimes they didn't. I assume you mean Surah 6:108 "And do not insult those they invoke other than Allah , lest they insult Allah in enmity without knowledge. Thus We have made pleasing to every community their deeds. Then to their Lord is their return, and He will inform them about what they used to do."
The only reason Muslims are commanded not to insult followers of other religions ONLY TO STOP THEM FROM INSULTING ALLAH.
There are many instances of Muslims in the Qu'ran and Hadiths not respecting the religions of those they meet. In the Hadiths (the writings of Muhammad's companions about his teachings and how and Islamic society should be structured), there's numerous examples of not respecting other religions; there's a time Muhammad's closest companion Abu-Bakr mocked pagans criticizing Muhammad's warmongering ways by telling them to suck the clitoris of their goddess al-Lat. https://www.youtube.com/watch?v=TJtNnkYVHh4&ab_channel=Acts17Apologetics
Not to mention; "Indeed, they who disbelieved among the People of the Scripture and the polytheists will be in the fire of Hell, abiding eternally therein. Those are the worst of creatures." Surah 98:6 (People of the Scripture are Jews and Christians. Keep in mind later Surahs in the Qu'ran abrogate - nullify - earlier Surahs).
If it's in the Qu'ran, what book, chapter and verse besides Surah 6:108, which I've already explained?