Maybe they've all read How to Win Friends and Influence People and applied everything in the book. Or maybe anybody who is paying attention could learn how to establish a friendly connection with others on their own.
But the point here is that liberal, conservative, or independent, someone's degree of niceness doesn't tell you what they believe or what they intend to do.
The reason I'm bringing this up is that many people will respond to your criticism of Islam with, "But I know several Muslims, and they are very nice people," as if the existence of nice Muslims means that Islamic doctrine couldn't possibly command intolerance or violence against non-Muslims. But that's ridiculous. Niceness and charm tell you nothing at all about the ideology someone subscribes to.
Make this point in your conversations, and make it clearly. Let's get this objection out of the way and get back to a real conversation about Islam.