I mean, he probably thought he has some rights beyond being unwillingly dragged out of there. That's not beyond the pale to be honest, when I've done nothing wrong I don't think I can be slammed into an armrest and physically dragged out of a plane.
Because he had a seat that he paid for, with urgent commitments at the other end. That should be the end of the discussion.
Airlines can't just be ordering passengers to leave the plane, much less assaulting them and carrying them off. They should have just kept upping the incentive.
This is going to cost United millions of dollars in damages and lost business.
Once the police turn up and tell him to leave did he think the Police were going to accept his answer of "no"? From what i understand even if you are a paying customer airlines have the right to remove you from the plane and either refund you the ticket or put you on another flight.
To make it clear i don't like what united did.