I guess the principle I am arguing for is when one side is prepared to use physical force (which they believe is justified) to remove someone from their private property, then the "trespasser" should abide by that (for the time-being), and seek legal remedy.
I see this as the only option to remaining civil. I don't see how society can function without violence without this being adhered to.
Also, when someone is charge with private security or as law enforcement, they should be respected where they physically enforce something. Again, once they have made up their mind to enforce something physically, I don't see a way to maintain civility in any other way than respecting their wishes.
In this case it was the airline's private property, and they felt justified to physically remove someone.
Now whether or not this is justified, is a matter for the courts to decide.