United CEO Defends Staff's Violent "Reaccomodation" Of "Belligerent" Passenger

In a letter to employees, United CEO Oscar Munoz said he was "upset to see and hear about what happened," but defended his staff's actions because the passenger had been "disruptive and belligerent." It seems not acquiescing to a computer's decision to select you for 'reaccomodation' is "disruptive" and warrants violence?
As The BBC reports, Mr Munoz has faced criticism on social media for his response to the incident.