The Maher panel in that video exemplifies how the left lives in a separate, hermetically-sealed, propagandist universe.
It's not just that the Left cannot see in themselves what they condemn in people who don't completely agree with them. It's that they consider their opinions and positions to be "enlightened" and that they must "bring us around" to those positions. Oh, and that those on the Left are weakened by their desire to not say or do anything offensive. All of this was discussed in the short video.
With this type of thinking and behavior we see on the Left, coupled with a complete absence of even a trace of introspection, negotiation and civil discourse is truly impossible.