For their smarmy, arrogant, condescending and unspoken assumption that their nihilistic, materialistic, socialistic/communistic, relativistic, humanistic Weltanschauung is the only valid POV, requiring that all others be either ignored or reported on as if they were strange growths discovered in a grass-hut cellar in Borneo. Further, for their startled, blink-eyed what-me? amazement act when they are confronted with this bias.
Dan
Dan---
You nailed it! Of course, it won't make it to Hollywood as as a script for an epic film documentary, "Joe McCarthy, We Have Buried You!--The end of truth in American media."