On his HBO show Real Time, Bill Maher, committed atheist, hosted Ross Douthat, a Christian and the author of Bad Religion. Maher maintains that religion has been the cause of all the world's suffering; Douthat reminds Maher about the Soviet Union and the millions of dead bodies. Here's the interesting part: Maher correctly identifies the belief behind those killings as secular religion.
It's a fun segment to watch. Maher and Douthat make good sparring partners.