Sorry, Doc.  Can't agree.  A fundamentalist is a fundamentalist.  Islam or Christian makes little difference.  The prohibitions of Leviticus have their counter-parts in the Koran.  They are all reading from different flavours of the Abrahamic playbook.  At the moment, Islamic fundamentalism is the source of a huge amount of suffering in the world.  The point of Atwood's tale is don't fool yourself into thinking that can't happen in the West.