I found the following in my own handwriting on the study guide where I was trying to transcribe as fast as I could what Rod was saying. He nails something here.
Secularism cannot compete with Islam as a worldview because you can't beat something with nothing. That's why Muslims don't view secularism as a threat. Christianity, however, is a threat, for it is something, and it is something very tangible that answers the longings of the human heart in a way that secularism can't.