What is a 'cultural Christian'?

Richard Dawkins calls himself a cultural Christian he says, "We are culturally a Christian country and I call myself a cultural Christian. I love hymns and Christmas carols and feel myself at home in the Christian ethos. I love the wonderful language of the Authorised version of the Bible. If I had to choose between Christianity and Islam I would choose Christianity every time. It seems to me to be a fundamentally decent religion. In so far as Christianity can be seen as a bulwark against Islam I think it’s a very good thing. I like to live in a culturally Christian country."

https://www.youtube.com/watch?v=COHgEFUFWyg