> That probably doesn't seem rational but remember loads of these people think the Bible is a true story.
Those are the (sizeable) subset who are obsessed with a literal interpretation of the Old Testament rather than the turn-the-other-cheek teachings of Christ, who is little more than a totem for these fundamentalists.
Arguably there is less harm in believing that Christ's ministry was historical than believing that Sodom and Gomorrah were historical.